Commit Graph

767 Commits

Author SHA1 Message Date
David Hildenbrand 4ba50cd335 virtio-mem: Big Block Mode (BBM) memory hotplug
Currently, we do not support device block sizes that exceed the Linux
memory block size. For example, having a device block size of 1 GiB (e.g.,
gigantic pages in the hypervisor) won't work with 128 MiB Linux memory
blocks.

Let's implement Big Block Mode (BBM), whereby we add/remove at least
one Linux memory block at a time. With a 1 GiB device block size, a Big
Block (BB) will cover 8 Linux memory blocks.

We'll keep registering the online_page_callback machinery, it will be used
for safe memory hotunplug in BBM next.

Note: BBM is properly prepared for variable-sized Linux memory
blocks that we might see in the future. So we won't care how many Linux
memory blocks a big block actually spans, and how the memory notifier is
called.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-26-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:27 -05:00
David Hildenbrand 01afdee29a virtio-mem: factor out adding/removing memory from Linux
Let's use wrappers for the low-level functions that dev_dbg/dev_warn
and work on addr + size, such that we can reuse them for adding/removing
in other granularity.

We only warn when adding memory failed, because that's something to pay
attention to. We won't warn when removing failed, we'll reuse that in
racy context soon (and we do have proper BUG_ON() statements in the
current cases where it must never happen).

Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-25-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:27 -05:00
David Hildenbrand d46dfb62f6 virtio-mem: memory notifier callbacks are specific to Sub Block Mode (SBM)
Let's rename accordingly.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-24-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:27 -05:00
David Hildenbrand 602ef89457 virito-mem: existing (un)plug functions are specific to Sub Block Mode (SBM)
Let's rename them accordingly. virtio_mem_plug_request() and
virtio_mem_unplug_request() will be handled separately.

Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-23-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:27 -05:00
David Hildenbrand 8a6f082bab virtio-mem: memory block ids are specific to Sub Block Mode (SBM)
Let's move first_mb_id/next_mb_id/last_usable_mb_id accordingly.

Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-22-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:27 -05:00
David Hildenbrand 905c4c5146 virtio-mem: nb_sb_per_mb and subblock_size are specific to Sub Block Mode (SBM)
Let's rename to "sbs_per_mb" and "sb_size" and move accordingly.

Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-21-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:27 -05:00
David Hildenbrand 54c6a6ba75 virito-mem: subblock states are specific to Sub Block Mode (SBM)
Let's rename and move accordingly. While at it, rename sb_bitmap to
"sb_states".

Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-20-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:27 -05:00
David Hildenbrand 99f0b55ea6 virtio-mem: memory block states are specific to Sub Block Mode (SBM)
let's use a new "sbm" sub-struct to hold SBM-specific state and rename +
move applicable definitions, functions, and variables (related to
memory block states).

While at it:
- Drop the "_STATE" part from memory block states
- Rename "nb_mb_state" to "mb_count"
- "set_mb_state" / "get_mb_state" vs. "mb_set_state" / "mb_get_state"
- Don't use lengthy "enum virtio_mem_smb_mb_state", simply use "uint8_t"

Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-19-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:26 -05:00
David Hildenbrand d561494425 virito-mem: document Sub Block Mode (SBM)
Let's add some documentation for the current mode - Sub Block Mode (SBM) -
to prepare for a new mode - Big Block Mode (BBM).

Follow-up patches will properly factor out the existing Sub Block Mode
(SBM) and implement Big Block Mode (BBM).

Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-18-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:26 -05:00
David Hildenbrand 98ff9f9411 virtio-mem: generalize handling when memory is getting onlined deferred
We don't want to add too much memory when it's not getting onlined
immediately, to avoid running OOM. Generalize the handling, to avoid
making use of memory block states. Use a threshold of 1 GiB for now.

Properly adjust the offline size when adding/removing memory. As we are
not always protected by a lock when touching the offline size, use an
atomic64_t. We don't care about races (e.g., someone offlining memory
while we are adding more), only about consistent values.

(1 GiB needs a memmap of ~16MiB - which sounds reasonable even for
 setups with little boot memory and (possibly) one virtio-mem device per
 node)

We don't want to retrigger when onlining is caused immediately by our
action (e.g., adding memory which immediately gets onlined), so use a
flag to indicate if the workqueue is active and use that as an
indicator whether to trigger a retry. This will also be especially relevant
for Big Block Mode (BBM), whereby we might re-online memory in case
offlining of another memory block failed.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-17-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:26 -05:00
David Hildenbrand 1d33c2caa8 virtio-mem: don't always trigger the workqueue when offlining memory
Let's trigger from offlining code only when we're not allowed to unplug
online memory. Handle the other case (memmap possibly freeing up another
memory block) when actually removing memory. We now also properly handle
the case when removing already offline memory blocks via
virtio_mem_mb_remove(). When removing via virtio_mem_remove(), when
unloading the driver, virtio_mem_retry() is a NOP and safe to use.

While at it, move retry handling when offlining out of
virtio_mem_notify_offline(), to share it with Big Block Mode (BBM)
soon.

This is a preparation for Big Block Mode (BBM), whereby we can see some
temporary offlining of memory blocks without actually making progress.
Imagine you have a Big Block that spans to Linux memory blocks. Assume
the first Linux memory blocks has no unmovable data on it. When we would
call offline_and_remove_memory() on the big block, we would
	1. Try to offline the first block. Works, notifiers triggered.
	   virtio_mem_retry() called.
	2. Try to offline the second block. Does not work.
	3. Re-online first block.
	4. Exit to main loop, exit workqueue.
	5. Retry immediately (due to virtio_mem_retry()), go to 1.
The result are endless retries.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-16-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:26 -05:00
David Hildenbrand 420066829b virtio-mem: drop last_mb_id
No longer used, let's drop it.

Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-15-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:26 -05:00
David Hildenbrand 835491c554 virtio-mem: generalize virtio_mem_overlaps_range()
Avoid using memory block ids. While at it, use uint64_t for
address/size.

This is a preparation for Big Block Mode (BBM).

Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-14-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:26 -05:00
David Hildenbrand 8464e3bdf2 virtio-mem: generalize virtio_mem_owned_mb()
Avoid using memory block ids. Rename it to virtio_mem_contains_range().

This is a preparation for Big Block Mode (BBM).

Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-13-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:26 -05:00
David Hildenbrand 989ff82527 virtio-mem: generalize check for added memory
Let's check by traversing busy system RAM resources instead, to avoid
relying on memory block states.

Don't use walk_system_ram_range(), as that works on pages and we want to
use the bare addresses we have easily at hand.

This is a preparation for Big Block Mode (BBM), which won't have memory
block states.

Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-12-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:26 -05:00
David Hildenbrand f2d799d591 virtio-mem: retry fake-offlining via alloc_contig_range() on ZONE_MOVABLE
ZONE_MOVABLE is supposed to give some guarantees, yet,
alloc_contig_range() isn't prepared to properly deal with some racy
cases properly (e.g., temporary page pinning when exiting processed, PCP).

Retry 5 times for now. There is certainly room for improvement in the
future.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-11-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:26 -05:00
David Hildenbrand 7a34c77dab virtio-mem: factor out handling of fake-offline pages in memory notifier
Let's factor out the core pieces and place the implementation next to
virtio_mem_fake_offline(). We'll reuse this functionality soon.

Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-10-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:26 -05:00
David Hildenbrand 89c486c47f virtio-mem: factor out fake-offlining into virtio_mem_fake_offline()
... which now matches virtio_mem_fake_online(). We'll reuse this
functionality soon.

Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-9-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:25 -05:00
David Hildenbrand 6beb3a9421 virtio-mem: print debug messages from virtio_mem_send_*_request()
Let's move the existing dev_dbg() into the functions, print if something
went wrong, and also print for virtio_mem_send_unplug_all_request().

Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-8-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:25 -05:00
David Hildenbrand 41e6215c6d virtio-mem: factor out calculation of the bit number within the subblock bitmap
The calculation is already complicated enough, let's limit it to one
location.

Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-7-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:25 -05:00
David Hildenbrand 2a6285114b virtio-mem: use "unsigned long" for nr_pages when fake onlining/offlining
No harm done, but let's be consistent.

Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-6-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:25 -05:00
David Hildenbrand d76944f80d virtio-mem: drop rc2 in virtio_mem_mb_plug_and_add()
We can drop rc2, we don't actually need the value.

Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-5-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:25 -05:00
David Hildenbrand 20b9150225 virtio-mem: simplify MAX_ORDER - 1 / pageblock_order handling
Let's use pageblock_nr_pages and MAX_ORDER_NR_PAGES instead where
possible to simplify.

Add a comment why we have that restriction for now.

Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-4-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:25 -05:00
David Hildenbrand 347202dc04 virtio-mem: more precise calculation in virtio_mem_mb_state_prepare_next_mb()
We actually need one byte less (next_mb_id is exclusive, first_mb_id is
inclusive). While at it, compact the code.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-3-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:25 -05:00
David Hildenbrand 6725f21157 virtio-mem: determine nid only once using memory_add_physaddr_to_nid()
Let's determine the target nid only once in case we have none specified -
usually, we'll end up with node 0 either way.

Reviewed-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20201112133815.13332-2-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:25 -05:00
Vlastimil Babka 8f424750ba mm, page_poison: remove CONFIG_PAGE_POISONING_NO_SANITY
CONFIG_PAGE_POISONING_NO_SANITY skips the check on page alloc whether the
poison pattern was corrupted, suggesting a use-after-free.  The motivation
to introduce it in commit 8823b1dbc0 ("mm/page_poison.c: enable
PAGE_POISONING as a separate option") was to simply sanitize freed pages,
optimally together with CONFIG_PAGE_POISONING_ZERO.

These days we have an init_on_free=1 boot option, which makes this use
case of page poisoning redundant.  For sanitizing, writing zeroes is
sufficient, there is pretty much no benefit from writing the 0xAA poison
pattern to freed pages, without checking it back on alloc.  Thus, remove
this option and suggest init_on_free instead in the main config's help.

Link: https://lkml.kernel.org/r/20201113104033.22907-5-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Laura Abbott <labbott@kernel.org>
Cc: Mateusz Nosek <mateusznosek0@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 12:13:46 -08:00
Vlastimil Babka 8db26a3d47 mm, page_poison: use static key more efficiently
Commit 11c9c7edae ("mm/page_poison.c: replace bool variable with static
key") changed page_poisoning_enabled() to a static key check.  However,
the function is not inlined, so each check still involves a function call
with overhead not eliminated when page poisoning is disabled.

Analogically to how debug_pagealloc is handled, this patch converts
page_poisoning_enabled() back to boolean check, and introduces
page_poisoning_enabled_static() for fast paths.  Both functions are
inlined.

The function kernel_poison_pages() is also called unconditionally and does
the static key check inside.  Remove it from there and put it to callers.
Also split it to two functions kernel_poison_pages() and
kernel_unpoison_pages() instead of the confusing bool parameter.

Also optimize the check that enables page poisoning instead of
debug_pagealloc for architectures without proper debug_pagealloc support.
Move the check to init_mem_debugging_and_hardening() to enable a single
static key instead of having two static branches in
page_poisoning_enabled_static().

Link: https://lkml.kernel.org/r/20201113104033.22907-3-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Laura Abbott <labbott@kernel.org>
Cc: Mateusz Nosek <mateusznosek0@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 12:13:46 -08:00
Linus Torvalds 9313f80263 vhost,vdpa,virtio: cleanups, fixes
A very quiet cycle, no new features.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio updates from Michael Tsirkin:
 "vhost, vdpa, and virtio cleanups and fixes

  A very quiet cycle, no new features"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  MAINTAINERS: add URL for virtio-mem
  vhost_vdpa: remove unnecessary spin_lock in vhost_vring_call
  vringh: fix __vringh_iov() when riov and wiov are different
  vdpa/mlx5: Setup driver only if VIRTIO_CONFIG_S_DRIVER_OK
  s390: virtio: PV needs VIRTIO I/O device protection
  virtio: let arch advertise guest's memory access restrictions
  vhost_vdpa: Fix duplicate included kernel.h
  vhost: reduce stack usage in log_used
  virtio-mem: Constify mem_id_table
  virtio_input: Constify id_table
  virtio-balloon: Constify id_table
  vdpa/mlx5: Fix failure to bring link up
  vdpa/mlx5: Make use of a specific 16 bit endianness API
2020-10-23 11:00:57 -07:00
Pierre Morel 0afa15e1a5 virtio: let arch advertise guest's memory access restrictions
An architecture may restrict host access to guest memory,
e.g. IBM s390 Secure Execution or AMD SEV.

Provide a new Kconfig entry the architecture can select,
CONFIG_ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS, when it provides
the arch_has_restricted_virtio_memory_access callback to advertise
to VIRTIO common code when the architecture restricts memory access
from the host.

The common code can then fail the probe for any device where
VIRTIO_F_ACCESS_PLATFORM is required, but not set.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Link: https://lore.kernel.org/r/1599728030-17085-2-git-send-email-pmorel@linux.ibm.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-10-21 10:34:12 -04:00
Rikard Falkeborn 7ab4de6002 virtio-mem: Constify mem_id_table
mem_id_table is not modified, so make it const to allow the compiler to
put it in read-only memory.

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Link: https://lore.kernel.org/r/20200911203509.26505-4-rikard.falkeborn@gmail.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
2020-10-21 10:34:10 -04:00
Rikard Falkeborn 7f90611693 virtio_input: Constify id_table
id_table is not modified, so make it const to allow the compiler to put
it in read-only memory.

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Link: https://lore.kernel.org/r/20200911203509.26505-3-rikard.falkeborn@gmail.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
2020-10-21 10:34:09 -04:00
Rikard Falkeborn bfec6c8307 virtio-balloon: Constify id_table
id_table is not modified, so make it const to allow the compiler to put
it in read-only memory.

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Link: https://lore.kernel.org/r/20200911203509.26505-2-rikard.falkeborn@gmail.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
2020-10-21 10:34:08 -04:00
David Hildenbrand 9b24247a24 virtio-mem: try to merge system ram resources
virtio-mem adds memory in memory block granularity, to be able to remove
it in the same granularity again later, and to grow slowly on demand.
This, however, results in quite a lot of resources when adding a lot of
memory.  Resources are effectively stored in a list-based tree.  Having a
lot of resources not only wastes memory, it also makes traversing that
tree more expensive, and makes /proc/iomem explode in size (e.g.,
requiring kexec-tools to manually merge resources later when e.g., trying
to create a kdump header).

Before this patch, we get (/proc/iomem) when hotplugging 2G via virtio-mem
on x86-64:
        [...]
        100000000-13fffffff : System RAM
        140000000-33fffffff : virtio0
          140000000-147ffffff : System RAM (virtio_mem)
          148000000-14fffffff : System RAM (virtio_mem)
          150000000-157ffffff : System RAM (virtio_mem)
          158000000-15fffffff : System RAM (virtio_mem)
          160000000-167ffffff : System RAM (virtio_mem)
          168000000-16fffffff : System RAM (virtio_mem)
          170000000-177ffffff : System RAM (virtio_mem)
          178000000-17fffffff : System RAM (virtio_mem)
          180000000-187ffffff : System RAM (virtio_mem)
          188000000-18fffffff : System RAM (virtio_mem)
          190000000-197ffffff : System RAM (virtio_mem)
          198000000-19fffffff : System RAM (virtio_mem)
          1a0000000-1a7ffffff : System RAM (virtio_mem)
          1a8000000-1afffffff : System RAM (virtio_mem)
          1b0000000-1b7ffffff : System RAM (virtio_mem)
          1b8000000-1bfffffff : System RAM (virtio_mem)
        3280000000-32ffffffff : PCI Bus 0000:00

With this patch, we get (/proc/iomem):
        [...]
        fffc0000-ffffffff : Reserved
        100000000-13fffffff : System RAM
        140000000-33fffffff : virtio0
          140000000-1bfffffff : System RAM (virtio_mem)
        3280000000-32ffffffff : PCI Bus 0000:00

Of course, with more hotplugged memory, it gets worse.  When unplugging
memory blocks again, try_remove_memory() (via offline_and_remove_memory())
will properly split the resource up again.

Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Wei Yang <richardw.yang@linux.intel.com>
Cc: Anton Blanchard <anton@ozlabs.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Juergen Gross <jgross@suse.com>
Cc: Julien Grall <julien@xen.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Leonardo Bras <leobras.c@gmail.com>
Cc: Libor Pechacek <lpechacek@suse.cz>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nathan Lynch <nathanl@linux.ibm.com>
Cc: "Oliver O'Halloran" <oohall@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pingfan Liu <kernelfans@gmail.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Roger Pau Monné <roger.pau@citrix.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Wei Liu <wei.liu@kernel.org>
Link: https://lkml.kernel.org/r/20200911103459.10306-7-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-16 11:11:18 -07:00
David Hildenbrand b611719978 mm/memory_hotplug: prepare passing flags to add_memory() and friends
We soon want to pass flags, e.g., to mark added System RAM resources.
mergeable.  Prepare for that.

This patch is based on a similar patch by Oscar Salvador:

https://lkml.kernel.org/r/20190625075227.15193-3-osalvador@suse.de

Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Juergen Gross <jgross@suse.com> # Xen related part
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Acked-by: Wei Liu <wei.liu@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Baoquan He <bhe@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: "Oliver O'Halloran" <oohall@gmail.com>
Cc: Pingfan Liu <kernelfans@gmail.com>
Cc: Nathan Lynch <nathanl@linux.ibm.com>
Cc: Libor Pechacek <lpechacek@suse.cz>
Cc: Anton Blanchard <anton@ozlabs.org>
Cc: Leonardo Bras <leobras.c@gmail.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Julien Grall <julien@xen.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Roger Pau Monné <roger.pau@citrix.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richardw.yang@linux.intel.com>
Link: https://lkml.kernel.org/r/20200911103459.10306-5-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-16 11:11:18 -07:00
Linus Torvalds 93b694d096 drm next for 5.10-rc1
New driver:
 Cadence MHDP8546 DisplayPort bridge driver
 
 core:
 - cross-driver scatterlist cleanups
 - devm_drm conversions
 - remove drm_dev_init
 - devm_drm_dev_alloc conversion
 
 ttm:
 - lots of refactoring and cleanups
 
 bridges:
 - chained bridge support in more drivers
 
 panel:
 - misc new panels
 
 scheduler:
 - cleanup priority levels
 
 displayport:
 - refactor i915 code into helpers for nouveau
 
 i915:
 - split into display and GT trees
 - WW locking refactoring in GEM
 - execbuf2 extension mechanism
 - syncobj timeline support
 - GEN 12 HOBL display powersaving
 - Rocket Lake display additions
 - Disable FBC on Tigerlake
 - Tigerlake Type-C + DP improvements
 - Hotplug interrupt refactoring
 
 amdgpu:
 - Sienna Cichlid updates
 - Navy Flounder updates
 - DCE6 (SI) support for DC
 - Plane rotation enabled
 - TMZ state info ioctl
 - PCIe DPC recovery support
 - DC interrupt handling refactor
 - OLED panel fixes
 
 amdkfd:
 - add SMI events for thermal throttling
 - SMI interface events ioctl update
 - process eviction counters
 
 radeon:
 - move to dma_ for allocations
 - expose sclk via sysfs
 
 msm:
 - DSI support for sm8150/sm8250
 - per-process GPU pagetable support
 - Displayport support
 
 mediatek:
 - move HDMI phy driver to PHY
 - convert mtk-dpi to bridge API
 - disable mt2701 tmds
 
 tegra:
 - bridge support
 
 exynos:
 - misc cleanups
 
 vc4:
 - dual display cleanups
 
 ast:
 - cleanups
 
 gma500:
 - conversion to GPIOd API
 
 hisilicon:
 - misc reworks
 
 ingenic:
 - clock handling and format improvements
 
 mcde:
 - DSI support
 
 mgag200:
 - desktop g200 support
 
 mxsfb:
 - i.MX7 + i.MX8M
 - alpha plane support
 
 panfrost:
 - devfreq support
 - amlogic SoC support
 
 ps8640:
 - EDID from eDP retrieval
 
 tidss:
 - AM65xx YUV workaround
 
 virtio:
 - virtio-gpu exported resources
 
 rcar-du:
 - R8A7742, R8A774E1 and R8A77961 support
 - YUV planar format fixes
 - non-visible plane handling
 - VSP device reference count fix
 - Kconfig fix to avoid displaying disabled options in .config
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Merge tag 'drm-next-2020-10-15' of git://anongit.freedesktop.org/drm/drm

Pull drm updates from Dave Airlie:
 "Not a major amount of change, the i915 trees got split into display
  and gt trees to better facilitate higher level review, and there's a
  major refactoring of i915 GEM locking to use more core kernel concepts
  (like ww-mutexes). msm gets per-process pagetables, older AMD SI cards
  get DC support, nouveau got a bump in displayport support with common
  code extraction from i915.

  Outside of drm this contains a couple of patches for hexint
  moduleparams which you've acked, and a virtio common code tree that
  you should also get via it's regular path.

  New driver:
   - Cadence MHDP8546 DisplayPort bridge driver

  core:
   - cross-driver scatterlist cleanups
   - devm_drm conversions
   - remove drm_dev_init
   - devm_drm_dev_alloc conversion

  ttm:
   - lots of refactoring and cleanups

  bridges:
   - chained bridge support in more drivers

  panel:
   - misc new panels

  scheduler:
   - cleanup priority levels

  displayport:
   - refactor i915 code into helpers for nouveau

  i915:
   - split into display and GT trees
   - WW locking refactoring in GEM
   - execbuf2 extension mechanism
   - syncobj timeline support
   - GEN 12 HOBL display powersaving
   - Rocket Lake display additions
   - Disable FBC on Tigerlake
   - Tigerlake Type-C + DP improvements
   - Hotplug interrupt refactoring

  amdgpu:
   - Sienna Cichlid updates
   - Navy Flounder updates
   - DCE6 (SI) support for DC
   - Plane rotation enabled
   - TMZ state info ioctl
   - PCIe DPC recovery support
   - DC interrupt handling refactor
   - OLED panel fixes

  amdkfd:
   - add SMI events for thermal throttling
   - SMI interface events ioctl update
   - process eviction counters

  radeon:
   - move to dma_ for allocations
   - expose sclk via sysfs

  msm:
   - DSI support for sm8150/sm8250
   - per-process GPU pagetable support
   - Displayport support

  mediatek:
   - move HDMI phy driver to PHY
   - convert mtk-dpi to bridge API
   - disable mt2701 tmds

  tegra:
   - bridge support

  exynos:
   - misc cleanups

  vc4:
   - dual display cleanups

  ast:
   - cleanups

  gma500:
   - conversion to GPIOd API

  hisilicon:
   - misc reworks

  ingenic:
   - clock handling and format improvements

  mcde:
   - DSI support

  mgag200:
   - desktop g200 support

  mxsfb:
   - i.MX7 + i.MX8M
   - alpha plane support

  panfrost:
   - devfreq support
   - amlogic SoC support

  ps8640:
   - EDID from eDP retrieval

  tidss:
   - AM65xx YUV workaround

  virtio:
   - virtio-gpu exported resources

  rcar-du:
   - R8A7742, R8A774E1 and R8A77961 support
   - YUV planar format fixes
   - non-visible plane handling
   - VSP device reference count fix
   - Kconfig fix to avoid displaying disabled options in .config"

* tag 'drm-next-2020-10-15' of git://anongit.freedesktop.org/drm/drm: (1494 commits)
  drm/ingenic: Fix bad revert
  drm/amdgpu: Fix invalid number of character '{' in amdgpu_acpi_init
  drm/amdgpu: Remove warning for virtual_display
  drm/amdgpu: kfd_initialized can be static
  drm/amd/pm: setup APU dpm clock table in SMU HW initialization
  drm/amdgpu: prevent spurious warning
  drm/amdgpu/swsmu: fix ARC build errors
  drm/amd/display: Fix OPTC_DATA_FORMAT programming
  drm/amd/display: Don't allow pstate if no support in blank
  drm/panfrost: increase readl_relaxed_poll_timeout values
  MAINTAINERS: Update entry for st7703 driver after the rename
  Revert "gpu/drm: ingenic: Add option to mmap GEM buffers cached"
  drm/amd/display: HDMI remote sink need mode validation for Linux
  drm/amd/display: Change to correct unit on audio rate
  drm/amd/display: Avoid set zero in the requested clk
  drm/amdgpu: align frag_end to covered address space
  drm/amdgpu: fix NULL pointer dereference for Renoir
  drm/vmwgfx: fix regression in thp code due to ttm init refactor.
  drm/amdgpu/swsmu: add interrupt work handler for smu11 parts
  drm/amdgpu/swsmu: add interrupt work function
  ...
2020-10-15 10:46:16 -07:00
David Hildenbrand 27f852795a virtio-mem: don't special-case ZONE_MOVABLE
When introducing virtio-mem, the semantics of ZONE_MOVABLE were rather
unclear, which is why we special-cased ZONE_MOVABLE such that partially
plugged blocks would never end up in ZONE_MOVABLE.

Now that the semantics are much clearer (and will be documented in a
follow-up patch including the new virtio-mem behavior), let's allow to
online partially plugged memory blocks to ZONE_MOVABLE and also consider
memory blocks that were onlined to ZONE_MOVABLE when unplugging memory.
While unplugged memory pages are, in general, unmovable, they can be
skipped when offlining memory.

virtio-mem only unplugs fairly big chunks (in the megabyte range) and
rather tries to shrink the memory region than randomly choosing memory.
In theory, if all other pages in the movable zone would be movable,
virtio-mem would only shrink that zone and not create any kind of
fragmentation.

In the future, we might want to remember the zone again and use the
information when (un)plugging memory.  For now, let's keep it simple.

Note: Support for defragmentation is planned, to deal with fragmentation
after unplug due to memory chunks within memory blocks that could not get
unplugged before (e.g., somebody pinning pages within ZONE_MOVABLE for a
longer time).

Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Qian Cai <cai@lca.pw>
Link: http://lkml.kernel.org/r/20200816125333.7434-6-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13 18:38:33 -07:00
Maxime Ripard 05e63c6a7e
Merge branch 'virtio-shm' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse into drm-misc-next
Topic pull request for core virtio changes that will be required by the DRM
driver.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>
From: Gurchetan Singh <gurchetansingh@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/CAAfnVBn2BzXWFY3hhjDxd5q0P2_JWn-HdkVxgS94x9keAUZiow@mail.gmail.com
2020-09-16 13:18:32 +02:00
Sebastien Boeuf 38e895487a virtio: Implement get_shm_region for MMIO transport
On MMIO a new set of registers is defined for finding SHM
regions.  Add their definitions and use them to find the region.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Cc: kvm@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-10 10:05:58 +02:00
Sebastien Boeuf 0dd4ff93f4 virtio: Implement get_shm_region for PCI transport
On PCI the shm regions are found using capability entries;
find a region by searching for the capability.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: kbuild test robot <lkp@intel.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Cc: kvm@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-10 10:05:58 +02:00
David Stevens 9fe2f89749 virtio: fix build for configs without dma-bufs
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: David Stevens <stevensd@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20200819031011.310180-1-stevensd@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2020-08-19 06:43:28 +02:00
Maxime Ripard d85ddd1318 Linux 5.9-rc1
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Merge v5.9-rc1 into drm-misc-next

Sam needs 5.9-rc1 to have dev_err_probe in to merge some patches.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>
2020-08-18 14:14:25 +02:00
David Stevens a0308938ec virtio: add dma-buf support for exported objects
This change adds a new flavor of dma-bufs that can be used by virtio
drivers to share exported objects. A virtio dma-buf can be queried by
virtio drivers to obtain the UUID which identifies the underlying
exported object.

Signed-off-by: David Stevens <stevensd@chromium.org>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200818071343.3461203-2-stevensd@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2020-08-18 10:01:44 +02:00
Krzysztof Kozlowski fe0580ac5c virtio: pci: constify ioreadX() iomem argument (as in generic implementation)
The ioreadX() helpers have inconsistent interface.  On some architectures
void *__iomem address argument is a pointer to const, on some not.

Implementations of ioreadX() do not modify the memory under the address so
they can be converted to a "const" version for const-safety and
consistency among architectures.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Allen Hubbe <allenbh@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Jon Mason <jdmason@kudzu.us>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Rich Felker <dalias@libc.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200709072837.5869-5-krzk@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-14 19:56:57 -07:00
Linus Torvalds 57b0779392 virtio: fixes, features
IRQ bypass support for vdpa and IFC
 MLX5 vdpa driver
 Endian-ness fixes for virtio drivers
 Misc other fixes
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio updates from Michael Tsirkin:

 - IRQ bypass support for vdpa and IFC

 - MLX5 vdpa driver

 - Endianness fixes for virtio drivers

 - Misc other fixes

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (71 commits)
  vdpa/mlx5: fix up endian-ness for mtu
  vdpa: Fix pointer math bug in vdpasim_get_config()
  vdpa/mlx5: Fix pointer math in mlx5_vdpa_get_config()
  vdpa/mlx5: fix memory allocation failure checks
  vdpa/mlx5: Fix uninitialised variable in core/mr.c
  vdpa_sim: init iommu lock
  virtio_config: fix up warnings on parisc
  vdpa/mlx5: Add VDPA driver for supported mlx5 devices
  vdpa/mlx5: Add shared memory registration code
  vdpa/mlx5: Add support library for mlx5 VDPA implementation
  vdpa/mlx5: Add hardware descriptive header file
  vdpa: Modify get_vq_state() to return error code
  net/vdpa: Use struct for set/get vq state
  vdpa: remove hard coded virtq num
  vdpasim: support batch updating
  vhost-vdpa: support IOTLB batching hints
  vhost-vdpa: support get/set backend features
  vhost: generialize backend features setting/getting
  vhost-vdpa: refine ioctl pre-processing
  vDPA: dont change vq irq after DRIVER_OK
  ...
2020-08-11 14:34:17 -07:00
Liao Pingfang 46af9adefd virtio_pci_modern: Fix the comment of virtio_pci_find_capability()
Fix the comment of virtio_pci_find_capability() by adding missing comment
for the last parameter: bars.

Fixes: 59a5b0f7bf ("virtio-pci: alloc only resources actually used.")
Signed-off-by: Liao Pingfang <liao.pingfang@zte.com.cn>
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Link: https://lore.kernel.org/r/1596455545-43556-1-git-send-email-wang.yi59@zte.com.cn
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2020-08-05 11:08:42 -04:00
Mao Wenan 481a0d7422 virtio_ring: Avoid loop when vq is broken in virtqueue_poll
The loop may exist if vq->broken is true,
virtqueue_get_buf_ctx_packed or virtqueue_get_buf_ctx_split
will return NULL, so virtnet_poll will reschedule napi to
receive packet, it will lead cpu usage(si) to 100%.

call trace as below:
virtnet_poll
	virtnet_receive
		virtqueue_get_buf_ctx
			virtqueue_get_buf_ctx_packed
			virtqueue_get_buf_ctx_split
	virtqueue_napi_complete
		virtqueue_poll           //return true
		virtqueue_napi_schedule //it will reschedule napi

to fix this, return false if vq is broken in virtqueue_poll.

Signed-off-by: Mao Wenan <wenan.mao@linux.alibaba.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/1596354249-96204-1-git-send-email-wenan.mao@linux.alibaba.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2020-08-05 11:08:41 -04:00
Michael S. Tsirkin 99e0d0488b virtio_mem: convert to LE accessors
Virtio mem is modern-only. Use LE accessors for config space.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-05 11:08:41 -04:00
Michael S. Tsirkin b025584098 virtio_input: convert to LE accessors
Virtio input is modern-only. Use LE accessors for config space.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-05 11:08:41 -04:00
Michael S. Tsirkin 805769d7c0 virtio_balloon: use LE config space accesses
Balloon is LE, it's cleaner to access it as such directly.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-05 11:08:41 -04:00
Michael S. Tsirkin 6399167347 virtio_vdpa: legacy features handling
We normally expect vdpa to use the modern interface.
However for consistency, let's use same APIs as vhost
for legacy guests.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-05 11:08:40 -04:00
Michael S. Tsirkin 8875bbba97 virtio_balloon: fix sparse warning
balloon uses virtio32_to_cpu instead of cpu_to_virtio32
to convert a native endian number to virtio.
No practical difference but makes sparse warn.
Fix it up.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
2020-08-05 09:30:19 -04:00
Linus Torvalds 99ea1521a0 Remove uninitialized_var() macro for v5.9-rc1
- Clean up non-trivial uses of uninitialized_var()
 - Update documentation and checkpatch for uninitialized_var() removal
 - Treewide removal of uninitialized_var()
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Merge tag 'uninit-macro-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull uninitialized_var() macro removal from Kees Cook:
 "This is long overdue, and has hidden too many bugs over the years. The
  series has several "by hand" fixes, and then a trivial treewide
  replacement.

   - Clean up non-trivial uses of uninitialized_var()

   - Update documentation and checkpatch for uninitialized_var() removal

   - Treewide removal of uninitialized_var()"

* tag 'uninit-macro-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  compiler: Remove uninitialized_var() macro
  treewide: Remove uninitialized_var() usage
  checkpatch: Remove awareness of uninitialized_var() macro
  mm/debug_vm_pgtable: Remove uninitialized_var() usage
  f2fs: Eliminate usage of uninitialized_var() macro
  media: sur40: Remove uninitialized_var() usage
  KVM: PPC: Book3S PR: Remove uninitialized_var() usage
  clk: spear: Remove uninitialized_var() usage
  clk: st: Remove uninitialized_var() usage
  spi: davinci: Remove uninitialized_var() usage
  ide: Remove uninitialized_var() usage
  rtlwifi: rtl8192cu: Remove uninitialized_var() usage
  b43: Remove uninitialized_var() usage
  drbd: Remove uninitialized_var() usage
  x86/mm/numa: Remove uninitialized_var() usage
  docs: deprecated.rst: Add uninitialized_var()
2020-08-04 13:49:43 -07:00
Michael S. Tsirkin 24b6842ade virtio: virtio_has_iommu_quirk -> virtio_has_dma_quirk
Now that the corresponding feature bit has been renamed,
rename the quirk too - it's about special ways to
do DMA, not necessarily about the IOMMU.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-03 16:11:42 -04:00
Michael S. Tsirkin 321bd21261 virtio: VIRTIO_F_IOMMU_PLATFORM -> VIRTIO_F_ACCESS_PLATFORM
Rename the bit to match latest virtio spec.
Add a compat macro to avoid breaking existing userspace.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
2020-08-03 16:11:42 -04:00
Weilong Chen a96b0d061d virtio-mem: Fix build error due to improper use 'select'
As noted in:
https://www.kernel.org/doc/Documentation/kbuild/kconfig-language.txt
"select should be used with care. select will force a symbol to a
value without visiting the dependencies."
Config VIRTIO_MEM should not select CONTIG_ALLOC directly.
Otherwise it will cause an error:
https://bugzilla.kernel.org/show_bug.cgi?id=208245

Signed-off-by: Weilong Chen <chenweilong@huawei.com>
Link: https://lore.kernel.org/r/20200619080333.194753-1-chenweilong@huawei.com
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
2020-07-30 11:28:17 -04:00
Michael S. Tsirkin 168c358af2 virtio_balloon: fix up endian-ness for free cmd id
free cmd id is read using virtio endian, spec says all fields
in balloon are LE. Fix it up.

Fixes: 86a559787e ("virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT")
Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Wei Wang <wei.w.wang@intel.com>
Acked-by: David Hildenbrand <david@redhat.com>
2020-07-29 13:24:30 -04:00
Alexander Duyck ca72cc3483 virtio-balloon: Document byte ordering of poison_val
The poison_val field in the virtio_balloon_config is treated as a
little-endian field by the host. Since we are currently only having to deal
with a single byte poison value this isn't a problem, however if the value
should ever expand it would cause byte ordering issues. Document that in
the code so that we know that if the value should ever expand we need to
byte swap the value on big-endian architectures.

Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Link: https://lore.kernel.org/r/20200713203539.17140.71425.stgit@localhost.localdomain
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
2020-07-29 13:24:30 -04:00
Linus Torvalds 23ee3e4e5b pci-v5.8-fixes-2
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Merge tag 'pci-v5.8-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci into master

Pull PCI fixes from Bjorn Helgaas:

 - Reject invalid IRQ 0 command line argument for virtio_mmio because
   IRQ 0 now generates warnings (Bjorn Helgaas)

 - Revert "PCI/PM: Assume ports without DLL Link Active train links in
   100 ms", which broke nouveau (Bjorn Helgaas)

* tag 'pci-v5.8-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  Revert "PCI/PM: Assume ports without DLL Link Active train links in 100 ms"
  virtio-mmio: Reject invalid IRQ 0 command line argument
2020-07-24 18:30:24 -07:00
Bjorn Helgaas 62ca18a089 virtio-mmio: Reject invalid IRQ 0 command line argument
The "virtio_mmio.device=" command line argument allows a user to specify
the size, address, and IRQ of a virtio device.  Previously the only
requirement for the IRQ was that it be an unsigned integer.

Zero is an unsigned integer but an invalid IRQ number, and after
a85a6c86c2 ("driver core: platform: Clarify that IRQ 0 is invalid"),
attempts to use IRQ 0 cause warnings.

If the user specifies IRQ 0, return failure instead of registering a device
with IRQ 0.

Fixes: a85a6c86c2 ("driver core: platform: Clarify that IRQ 0 is invalid")
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
2020-07-22 10:31:45 -05:00
Kees Cook 3f649ab728 treewide: Remove uninitialized_var() usage
Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.

In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:

git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
	xargs perl -pi -e \
		's/\buninitialized_var\(([^\)]+)\)/\1/g;
		 s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'

drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.

No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.

[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/

Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers
Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs
Signed-off-by: Kees Cook <keescook@chromium.org>
2020-07-16 12:35:15 -07:00
David Hildenbrand b3562c6087 virtio-mem: add memory via add_memory_driver_managed()
Virtio-mem managed memory is always detected and added by the virtio-mem
driver, never using something like the firmware-provided memory map.
This is the case after an ordinary system reboot, and has to be guaranteed
after kexec. Especially, virtio-mem added memory resources can contain
inaccessible parts ("unblocked memory blocks"), blindly forwarding them
to a kexec kernel is dangerous, as unplugged memory will get accessed
(esp. written).

Let's use the new way of adding special driver-managed memory introduced
in commit 7b7b27214b ("mm/memory_hotplug: introduce
add_memory_driver_managed()").

This will result in no entries in /sys/firmware/memmap ("raw firmware-
provided memory map"), the memory resource will be flagged
IORESOURCE_MEM_DRIVER_MANAGED (esp., kexec_file_load() will not place
kexec images on this memory), and it is exposed as "System RAM
(virtio_mem)" in /proc/iomem, so esp. kexec-tools can properly handle it.

Example /proc/iomem before this change:
  [...]
  140000000-333ffffff : virtio0
    140000000-147ffffff : System RAM
  334000000-533ffffff : virtio1
    338000000-33fffffff : System RAM
    340000000-347ffffff : System RAM
    348000000-34fffffff : System RAM
  [...]

Example /proc/iomem after this change:
  [...]
  140000000-333ffffff : virtio0
    140000000-147ffffff : System RAM (virtio_mem)
  334000000-533ffffff : virtio1
    338000000-33fffffff : System RAM (virtio_mem)
    340000000-347ffffff : System RAM (virtio_mem)
    348000000-34fffffff : System RAM (virtio_mem)
  [...]

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: teawater <teawaterz@linux.alibaba.com>
Fixes: 5f1f79bbc9 ("virtio-mem: Paravirtualized memory hotplug")
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200611093518.5737-1-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
2020-06-22 12:34:21 -04:00
Dan Carpenter 1c3d69ab53 virtio-mem: silence a static checker warning
Smatch complains that "rc" can be uninitialized if we hit the "break;"
statement on the first iteration through the loop.  I suspect that this
can't happen in real life, but returning a zero literal is cleaner and
silence the static checker warning.

Fixes: 5f1f79bbc9 ("virtio-mem: Paravirtualized memory hotplug")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20200610085911.GC5439@mwanda
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-22 12:34:21 -04:00
Masahiro Yamada a7f7f6248d treewide: replace '---help---' in Kconfig files with 'help'
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.

This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.

There are a variety of indentation styles found.

  a) 4 spaces + '---help---'
  b) 7 spaces + '---help---'
  c) 8 spaces + '---help---'
  d) 1 space + 1 tab + '---help---'
  e) 1 tab + '---help---'    (correct indentation)
  f) 1 tab + 1 space + '---help---'
  g) 1 tab + 2 spaces + '---help---'

In order to convert all of them to 1 tab + 'help', I ran the
following commend:

  $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-14 01:57:21 +09:00
Michael S. Tsirkin 544fc7dbbf virtio_mem: convert device block size into 64bit
If subblock size is large (e.g. 1G) 32 bit math involving it
can overflow. Rather than try to catch all instances of that,
let's tweak block size to 64 bit.

It ripples through UAPI which is an ABI change, but it's not too late to
make it, and it will allow supporting >4Gbyte blocks while might
become necessary down the road.

Fixes: 5f1f79bbc9 ("virtio-mem: Paravirtualized memory hotplug")
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
2020-06-09 06:42:06 -04:00
Michael S. Tsirkin b3fb6de7c6 virtio-mem: drop unnecessary initialization
rc is initialized to -ENIVAL but that's never used. Drop it.

Fixes: 5f1f79bbc9 ("virtio-mem: Paravirtualized memory hotplug")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
2020-06-08 05:12:52 -04:00
David Hildenbrand fce8afd76e virtio-mem: Don't rely on implicit compiler padding for requests
The compiler will add padding after the last member, make that explicit.
The size of a request is always 24 bytes. The size of a response always
10 bytes. Add compile-time checks.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: teawater <teawaterz@linux.alibaba.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200515101402.16597-1-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand 72f9525ad7 virtio-mem: Try to unplug the complete online memory block first
Right now, we always try to unplug single subblocks when processing an
online memory block. Let's try to unplug the complete online memory block
first, in case it is fully plugged and the unplug request is large
enough. Fallback to single subblocks in case the memory block cannot get
unplugged as a whole.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-16-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand 8d4edcfe78 virtio-mem: Use -ETXTBSY as error code if the device is busy
Let's be able to distinguish if the device or if memory is busy.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-15-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand 562e08cd24 virtio-mem: Unplug subblocks right-to-left
We unplug blocks right-to-left, let's also unplug subblocks within a block
right-to-left.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-14-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand 3c42e198e6 virtio-mem: Drop manual check for already present memory
Registering our parent resource will fail if any memory is still present
(e.g., because somebody unloaded the driver and tries to reload it). No
need for the manual check.

Move our "unplug all" handling to after registering the resource.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-13-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand ebf71552bb virtio-mem: Add parent resource for all added "System RAM"
Let's add a parent resource, named after the virtio device (inspired by
drivers/dax/kmem.c). This allows user space to identify which memory
belongs to which virtio-mem device.

With this change and two virtio-mem devices:
	:/# cat /proc/iomem
	00000000-00000fff : Reserved
	00001000-0009fbff : System RAM
	[...]
	140000000-333ffffff : virtio0
	  140000000-147ffffff : System RAM
	  148000000-14fffffff : System RAM
	  150000000-157ffffff : System RAM
	[...]
	334000000-3033ffffff : virtio1
	  338000000-33fffffff : System RAM
	  340000000-347ffffff : System RAM
	  348000000-34fffffff : System RAM
	[...]

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-12-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand 23e77b5dc9 virtio-mem: Better retry handling
Let's start with a retry interval of 5 seconds and double the time until
we reach 5 minutes, in case we keep getting errors. Reset the retry
interval in case we succeeded.

The two main reasons for having to retry are
- The hypervisor is busy and cannot process our request
- We cannot reach the desired requested_size (esp., not enough memory can
  get unplugged because we can't allocate any subblocks).

Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-11-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand a573238786 virtio-mem: Offline and remove completely unplugged memory blocks
Let's offline+remove memory blocks once all subblocks are unplugged. We
can use the new Linux MM interface for that. As no memory is in use
anymore, this shouldn't take a long time and shouldn't fail. There might
be corner cases where the offlining could still fail (especially, if
another notifier NACKs the offlining request).

Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-10-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand 8e5c921ca0 virtio-mem: Allow to offline partially unplugged memory blocks
Dropping the reference count of PageOffline() pages during MEM_GOING_ONLINE
allows offlining code to skip them. However, we also have to clear
PG_reserved, because PG_reserved pages get detected as unmovable right
away. Take care of restoring the reference count when offlining is
canceled.

Clarify why we don't have to perform any action when unloading the
driver. Also, let's add a warning if anybody is still holding a
reference to unplugged pages when offlining.

Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-8-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand 255f598507 virtio-mem: Paravirtualized memory hotunplug part 2
We also want to unplug online memory (contained in online memory blocks
and, therefore, managed by the buddy), and eventually replug it later.

When requested to unplug memory, we use alloc_contig_range() to allocate
subblocks in online memory blocks (so we are the owner) and send them to
our hypervisor. When requested to plug memory, we can replug such memory
using free_contig_range() after asking our hypervisor.

We also want to mark all allocated pages PG_offline, so nobody will
touch them. To differentiate pages that were never onlined when
onlining the memory block from pages allocated via alloc_contig_range(), we
use PageDirty(). Based on this flag, virtio_mem_fake_online() can either
online the pages for the first time or use free_contig_range().

It is worth noting that there are no guarantees on how much memory can
actually get unplugged again. All device memory might completely be
fragmented with unmovable data, such that no subblock can get unplugged.

We are not touching the ZONE_MOVABLE. If memory is onlined to the
ZONE_MOVABLE, it can only get unplugged after that memory was offlined
manually by user space. In normal operation, virtio-mem memory is
suggested to be onlined to ZONE_NORMAL. In the future, we will try to
make unplug more likely to succeed.

Add a module parameter to control if online memory shall be touched.

As we want to access alloc_contig_range()/free_contig_range() from
kernel module context, export the symbols.

Note: Whenever virtio-mem uses alloc_contig_range(), all affected pages
are on the same node, in the same zone, and contain no holes.

Acked-by: Michal Hocko <mhocko@suse.com> # to export contig range allocator API
Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Alexander Potapenko <glider@google.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-6-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand c627ff5d98 virtio-mem: Paravirtualized memory hotunplug part 1
Unplugging subblocks of memory blocks that are offline is easy. All we
have to do is watch out for concurrent onlining activity.

Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-5-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand f2af6d3978 virtio-mem: Allow to specify an ACPI PXM as nid
We want to allow to specify (similar as for a DIMM), to which node a
virtio-mem device (and, therefore, its memory) belongs. Add a new
virtio-mem feature flag and export pxm_to_node, so it can be used in kernel
module context.

Acked-by: Michal Hocko <mhocko@suse.com> # for the export
Acked-by: "Rafael J. Wysocki" <rafael@kernel.org> # for the export
Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Len Brown <lenb@kernel.org>
Cc: linux-acpi@vger.kernel.org
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-4-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
David Hildenbrand 5f1f79bbc9 virtio-mem: Paravirtualized memory hotplug
Each virtio-mem device owns exactly one memory region. It is responsible
for adding/removing memory from that memory region on request.

When the device driver starts up, the requested amount of memory is
queried and then plugged to Linux. On request, further memory can be
plugged or unplugged. This patch only implements the plugging part.

On x86-64, memory can currently be plugged in 4MB ("subblock") granularity.
When required, a new memory block will be added (e.g., usually 128MB on
x86-64) in order to plug more subblocks. Only x86-64 was tested for now.

The online_page callback is used to keep unplugged subblocks offline
when onlining memory - similar to the Hyper-V balloon driver. Unplugged
pages are marked PG_offline, to tell dump tools (e.g., makedumpfile) to
skip them.

User space is usually responsible for onlining the added memory. The
memory hotplug notifier is used to synchronize virtio-mem activity
against memory onlining/offlining.

Each virtio-mem device can belong to a NUMA node, which allows us to
easily add/remove small chunks of memory to/from a specific NUMA node by
using multiple virtio-mem devices. Something that works even when the
guest has no idea about the NUMA topology.

One way to view virtio-mem is as a "resizable DIMM" or a DIMM with many
"sub-DIMMS".

This patch directly introduces the basic infrastructure to implement memory
unplug. Especially the memory block states and subblock bitmaps will be
heavily used there.

Notes:
- In case memory is to be onlined by user space, we limit the amount of
  offline memory blocks, to not run out of memory. This is esp. an
  issue if memory is added faster than it is getting onlined.
- Suspend/Hibernate is not supported due to the way virtio-mem devices
  behave. Limited support might be possible in the future.
- Reloading the device driver is not supported.

Reviewed-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Tested-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
Cc: linux-acpi@vger.kernel.org
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200507140139.17083-2-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:52 -04:00
Alexander Duyck fb69c2c896 virtio-balloon: Disable free page reporting if page poison reporting is not enabled
We should disable free page reporting if page poisoning is enabled but we
cannot report it via the balloon interface. This way we can avoid the
possibility of corrupting guest memory. Normally the page poisoning feature
should always be present when free page reporting is enabled on the
hypervisor, however this allows us to correctly handle a case of the
virtio-balloon device being possibly misconfigured.

Fixes: 5d757c8d518d ("virtio-balloon: add support for providing free page reports to host")
Cc: stable@vger.kernel.org
Acked-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Link: https://lore.kernel.org/r/20200508173732.17877.85060.stgit@localhost.localdomain
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04 15:36:51 -04:00
Markus Elfring 0c35c67412 virtio-mmio: Delete an error message in vm_find_vqs()
The function “platform_get_irq” can log an error already.
Thus omit a redundant message for the exception handling in the
calling function.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Link: https://lore.kernel.org/r/9e27bc4a-cfa1-7818-dc25-8ad308816b30@web.de
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-02 02:45:13 -04:00
Matej Genci e7c8cc35a6 virtio: add VIRTIO_RING_NO_LEGACY
Add macro to disable legacy vring functions.

Signed-off-by: Matej Genci <matej.genci@nutanix.com>
Link: https://lore.kernel.org/r/20190911124942.243713-1-matej.genci@nutanix.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-02 02:45:13 -04:00
Alexander Duyck 31ba514b2f virtio-balloon: Avoid using the word 'report' when referring to free page hinting
It can be confusing to have multiple features within the same driver that
are using the same verbage. As such this patch is creating a union of
free_page_report_cmd_id with free_page_hint_cmd_id so that we can clean-up
the userspace code a bit in terms of readability while maintaining the
functionality of legacy code.

Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Link: https://lore.kernel.org/r/20200415174318.13597.99753.stgit@localhost.localdomain
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-17 06:05:30 -04:00
Jason Yan dc39cbb4e8 virtio-balloon: make virtballoon_free_page_report() static
Fix the following sparse warning:

drivers/virtio/virtio_balloon.c:168:5: warning: symbol
'virtballoon_free_page_report' was not declared. Should it be static?

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Link: https://lore.kernel.org/r/20200409085047.45483-1-yanaijie@huawei.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-17 06:05:30 -04:00
Michael S. Tsirkin 58ad13729a vdpa: make vhost, virtio depend on menu
If user did not configure any vdpa drivers, neither vhost
nor virtio vdpa are going to be useful. So there's no point
in prompting for these and selecting vdpa core automatically.
Simplify configuration by making virtio and vhost vdpa
drivers depend on vdpa menu entry. Once done, we no longer
need a separate menu entry, so also get rid of this.
While at it, fix up the IFC entry: VDPA->vDPA for consistency
with other places.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2020-04-17 06:05:30 -04:00
Michael S. Tsirkin f091abe806 virtio_input: pull in slab.h
In preparation to virtio header changes, include slab.h directly as
this module is using it.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-17 06:05:29 -04:00
Linus Torvalds 9bb715260e virtio: fixes, vdpa
Some bug fixes.
 The new vdpa subsystem with two first drivers.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio updates from Michael Tsirkin:

 - Some bug fixes

 - The new vdpa subsystem with two first drivers

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio-balloon: Revert "virtio-balloon: Switch back to OOM handler for VIRTIO_BALLOON_F_DEFLATE_ON_OOM"
  vdpa: move to drivers/vdpa
  virtio: Intel IFC VF driver for VDPA
  vdpasim: vDPA device simulator
  vhost: introduce vDPA-based backend
  virtio: introduce a vDPA based transport
  vDPA: introduce vDPA bus
  vringh: IOTLB support
  vhost: factor out IOTLB
  vhost: allow per device message handler
  vhost: refine vhost and vringh kconfig
  virtio-balloon: Switch back to OOM handler for VIRTIO_BALLOON_F_DEFLATE_ON_OOM
  virtio-net: Introduce hash report feature
  virtio-net: Introduce RSS receive steering feature
  virtio-net: Introduce extended RSC feature
  tools/virtio: option to build an out of tree module
2020-04-08 10:51:53 -07:00
David Hildenbrand da10329cb0 virtio-balloon: switch back to OOM handler for VIRTIO_BALLOON_F_DEFLATE_ON_OOM
Commit 71994620bb ("virtio_balloon: replace oom notifier with shrinker")
changed the behavior when deflation happens automatically.  Instead of
deflating when called by the OOM handler, the shrinker is used.

However, the balloon is not simply some other slab cache that should be
shrunk when under memory pressure.  The shrinker does not have a concept
of priorities yet, so this behavior cannot be configured.  Eventually once
that is in place, we might want to switch back after doing proper testing.

There was a report that this results in undesired side effects when
inflating the balloon to shrink the page cache. [1]
	"When inflating the balloon against page cache (i.e. no free memory
	 remains) vmscan.c will both shrink page cache, but also invoke the
	 shrinkers -- including the balloon's shrinker. So the balloon
	 driver allocates memory which requires reclaim, vmscan gets this
	 memory by shrinking the balloon, and then the driver adds the
	 memory back to the balloon. Basically a busy no-op."

The name "deflate on OOM" makes it pretty clear when deflation should
happen - after other approaches to reclaim memory failed, not while
reclaiming. This allows to minimize the footprint of a guest - memory
will only be taken out of the balloon when really needed.

Keep using the shrinker for VIRTIO_BALLOON_F_FREE_PAGE_HINT, because
this has no such side effects. Always register the shrinker with
VIRTIO_BALLOON_F_FREE_PAGE_HINT now. We are always allowed to reuse free
pages that are still to be processed by the guest. The hypervisor takes
care of identifying and resolving possible races between processing a
hinting request and the guest reusing a page.

In contrast to pre commit 71994620bb ("virtio_balloon: replace oom
notifier with shrinker"), don't add a module parameter to configure the
number of pages to deflate on OOM. Can be re-added if really needed.
Also, pay attention that leak_balloon() returns the number of 4k pages -
convert it properly in virtio_balloon_oom_notify().

Testing done by Tyler for future reference:
  Test setup: VM with 16 CPU, 64GB RAM. Running Debian 10. We have a 42
  GB file full of random bytes that we continually cat to /dev/null.
  This fills the page cache as the file is read. Meanwhile, we trigger
  the balloon to inflate, with a target size of 53 GB. This setup causes
  the balloon inflation to pressure the page cache as the page cache is
  also trying to grow. Afterwards we shrink the balloon back to zero (so
  total deflate == total inflate).

  Without this patch (kernel 4.19.0-5):
  Inflation never reaches the target until we stop the "cat file >
  /dev/null" process. Total inflation time was 542 seconds. The longest
  period that made no net forward progress was 315 seconds.
    Result of "grep balloon /proc/vmstat" after the test:
    balloon_inflate 154828377
    balloon_deflate 154828377

  With this patch (kernel 5.6.0-rc4+):
  Total inflation duration was 63 seconds. No deflate-queue activity
  occurs when pressuring the page-cache.
    Result of "grep balloon /proc/vmstat" after the test:
    balloon_inflate 12968539
    balloon_deflate 12968539

  Conclusion: This patch fixes the issue.  In the test it reduced
  inflate/deflate activity by 12x, and reduced inflation time by 8.6x.
  But more importantly, if we hadn't killed the "cat file > /dev/null"
  process then, without the patch, the inflation process would never reach
  the target.

[1] https://www.spinics.net/lists/linux-virtualization/msg40863.html

Link: http://lkml.kernel.org/r/20200311135523.18512-2-david@redhat.com
Fixes: 71994620bb ("virtio_balloon: replace oom notifier with shrinker")
Signed-off-by: David Hildenbrand <david@redhat.com>
Reported-by: Tyler Sanderson <tysand@google.com>
Tested-by: Tyler Sanderson <tysand@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Wei Wang <wei.w.wang@intel.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Michal Hocko <mhocko@kernel.org>

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:39 -07:00
Alexander Duyck b0c504f154 virtio-balloon: add support for providing free page reports to host
Add support for the page reporting feature provided by virtio-balloon.
Reporting differs from the regular balloon functionality in that is is
much less durable than a standard memory balloon.  Instead of creating a
list of pages that cannot be accessed the pages are only inaccessible
while they are being indicated to the virtio interface.  Once the
interface has acknowledged them they are placed back into their respective
free lists and are once again accessible by the guest system.

Unlike a standard balloon we don't inflate and deflate the pages.  Instead
we perform the reporting, and once the reporting is completed it is
assumed that the page has been dropped from the guest and will be faulted
back in the next time the page is accessed.

Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Nitesh Narayan Lal <nitesh@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pankaj Gupta <pagupta@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Wang <wei.w.wang@intel.com>
Cc: Yang Zhang <yang.zhang.wz@gmail.com>
Cc: wei qi <weiqi4@huawei.com>
Link: http://lkml.kernel.org/r/20200211224657.29318.68624.stgit@localhost.localdomain
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:39 -07:00
Alexander Duyck d74b78fabe virtio-balloon: pull page poisoning config out of free page hinting
Currently the page poisoning setting wasn't being enabled unless free page
hinting was enabled.  However we will need the page poisoning tracking
logic as well for free page reporting.  As such pull it out and make it a
separate bit of config in the probe function.

In addition we need to add support for the more recent init_on_free
feature which expects a behavior similar to page poisoning in that we
expect the page to be pre-zeroed.

Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Nitesh Narayan Lal <nitesh@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pankaj Gupta <pagupta@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Wang <wei.w.wang@intel.com>
Cc: Yang Zhang <yang.zhang.wz@gmail.com>
Cc: wei qi <weiqi4@huawei.com>
Link: http://lkml.kernel.org/r/20200211224646.29318.695.stgit@localhost.localdomain
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:38 -07:00
Michael S. Tsirkin 835a6a649d virtio-balloon: Revert "virtio-balloon: Switch back to OOM handler for VIRTIO_BALLOON_F_DEFLATE_ON_OOM"
This reverts commit 5a6b4cc5b7.

It has been queued properly in the akpm tree, this version is just
creating conflicts.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-07 05:44:57 -04:00
Michael S. Tsirkin c9b9f5f8c0 vdpa: move to drivers/vdpa
We have both vhost and virtio drivers that depend on vdpa.
It's easier to locate it at a top level directory otherwise
we run into issues e.g. if vhost is built-in but virtio
is modular.  Let's just move it up a level.

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-02 10:41:40 -04:00
Zhu Lingshan 5a2414bc45 virtio: Intel IFC VF driver for VDPA
This commit introduced two layers to drive IFC VF:

(1) ifcvf_base layer, which handles IFC VF NIC hardware operations and
    configurations.

(2) ifcvf_main layer, which complies to VDPA bus framework,
    implemented device operations for VDPA bus, handles device probe,
    bus attaching, vring operations, etc.

Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Signed-off-by: Bie Tiwei <tiwei.bie@intel.com>
Signed-off-by: Wang Xiao <xiao.w.wang@intel.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200326140125.19794-10-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-02 10:41:40 -04:00
Jason Wang 2c53d0f64c vdpasim: vDPA device simulator
This patch implements a software vDPA networking device. The datapath
is implemented through vringh and workqueue. The device has an on-chip
IOMMU which translates IOVA to PA. For kernel virtio drivers, vDPA
simulator driver provides dma_ops. For vhost driers, set_map() methods
of vdpa_config_ops is implemented to accept mappings from vhost.

Currently, vDPA device simulator will loopback TX traffic to RX. So
the main use case for the device is vDPA feature testing, prototyping
and development.

Note, there's no management API implemented, a vDPA device will be
registered once the module is probed. We need to handle this in the
future development.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200326140125.19794-9-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-02 10:41:40 -04:00
Jason Wang c043b4a8cf virtio: introduce a vDPA based transport
This patch introduces a vDPA transport for virtio. This is used to
use kernel virtio driver to drive the vDPA device that is capable
of populating virtqueue directly.

A new virtio-vdpa driver will be registered to the vDPA bus, when a
new virtio-vdpa device is probed, it will register the device with
vdpa based config ops. This means it is a software transport between
vDPA driver and vDPA device. The transport was implemented through
bus_ops of vDPA parent.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200326140125.19794-7-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-01 12:06:26 -04:00
Jason Wang 961e9c8407 vDPA: introduce vDPA bus
vDPA device is a device that uses a datapath which complies with the
virtio specifications with vendor specific control path. vDPA devices
can be both physically located on the hardware or emulated by
software. vDPA hardware devices are usually implemented through PCIE
with the following types:

- PF (Physical Function) - A single Physical Function
- VF (Virtual Function) - Device that supports single root I/O
  virtualization (SR-IOV). Its Virtual Function (VF) represents a
  virtualized instance of the device that can be assigned to different
  partitions
- ADI (Assignable Device Interface) and its equivalents - With
  technologies such as Intel Scalable IOV, a virtual device (VDEV)
  composed by host OS utilizing one or more ADIs. Or its equivalent
  like SF (Sub function) from Mellanox.

>From a driver's perspective, depends on how and where the DMA
translation is done, vDPA devices are split into two types:

- Platform specific DMA translation - From the driver's perspective,
  the device can be used on a platform where device access to data in
  memory is limited and/or translated. An example is a PCIE vDPA whose
  DMA request was tagged via a bus (e.g PCIE) specific way. DMA
  translation and protection are done at PCIE bus IOMMU level.
- Device specific DMA translation - The device implements DMA
  isolation and protection through its own logic. An example is a vDPA
  device which uses on-chip IOMMU.

To hide the differences and complexity of the above types for a vDPA
device/IOMMU options and in order to present a generic virtio device
to the upper layer, a device agnostic framework is required.

This patch introduces a software vDPA bus which abstracts the
common attributes of vDPA device, vDPA bus driver and the
communication method (vdpa_config_ops) between the vDPA device
abstraction and the vDPA bus driver. This allows multiple types of
drivers to be used for vDPA device like the virtio_vdpa and vhost_vdpa
driver to operate on the bus and allow vDPA device could be used by
either kernel virtio driver or userspace vhost drivers as:

   virtio drivers  vhost drivers
          |             |
    [virtio bus]   [vhost uAPI]
          |             |
   virtio device   vhost device
   virtio_vdpa drv vhost_vdpa drv
             \       /
            [vDPA bus]
                 |
            vDPA device
            hardware drv
                 |
            [hardware bus]
                 |
            vDPA hardware

With the abstraction of vDPA bus and vDPA bus operations, the
difference and complexity of the under layer hardware is hidden from
upper layer. The vDPA bus drivers on top can use a unified
vdpa_config_ops to control different types of vDPA device.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200326140125.19794-6-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-01 12:06:26 -04:00
David Hildenbrand 5a6b4cc5b7 virtio-balloon: Switch back to OOM handler for VIRTIO_BALLOON_F_DEFLATE_ON_OOM
Commit 71994620bb ("virtio_balloon: replace oom notifier with shrinker")
changed the behavior when deflation happens automatically. Instead of
deflating when called by the OOM handler, the shrinker is used.

However, the balloon is not simply some slab cache that should be
shrunk when under memory pressure. The shrinker does not have a concept of
priorities, so this behavior cannot be configured.

There was a report that this results in undesired side effects when
inflating the balloon to shrink the page cache. [1]
	"When inflating the balloon against page cache (i.e. no free memory
	 remains) vmscan.c will both shrink page cache, but also invoke the
	 shrinkers -- including the balloon's shrinker. So the balloon
	 driver allocates memory which requires reclaim, vmscan gets this
	 memory by shrinking the balloon, and then the driver adds the
	 memory back to the balloon. Basically a busy no-op."

The name "deflate on OOM" makes it pretty clear when deflation should
happen - after other approaches to reclaim memory failed, not while
reclaiming. This allows to minimize the footprint of a guest - memory
will only be taken out of the balloon when really needed.

Especially, a drop_slab() will result in the whole balloon getting
deflated - undesired. While handling it via the OOM handler might not be
perfect, it keeps existing behavior. If we want a different behavior, then
we need a new feature bit and document it properly (although, there should
be a clear use case and the intended effects should be well described).

Keep using the shrinker for VIRTIO_BALLOON_F_FREE_PAGE_HINT, because
this has no such side effects. Always register the shrinker with
VIRTIO_BALLOON_F_FREE_PAGE_HINT now. We are always allowed to reuse free
pages that are still to be processed by the guest. The hypervisor takes
care of identifying and resolving possible races between processing a
hinting request and the guest reusing a page.

In contrast to pre commit 71994620bb ("virtio_balloon: replace oom
notifier with shrinker"), don't add a moodule parameter to configure the
number of pages to deflate on OOM. Can be re-added if really needed.
Also, pay attention that leak_balloon() returns the number of 4k pages -
convert it properly in virtio_balloon_oom_notify().

Note1: using the OOM handler is frowned upon, but it really is what we
       need for this feature.

Note2: without VIRTIO_BALLOON_F_MUST_TELL_HOST (iow, always with QEMU) we
       could actually skip sending deflation requests to our hypervisor,
       making the OOM path *very* simple. Besically freeing pages and
       updating the balloon. If the communication with the host ever
       becomes a problem on this call path.

[1] https://www.spinics.net/lists/linux-virtualization/msg40863.html

Test report by Tyler Sanderson:

Test setup: VM with 16 CPU, 64GB RAM. Running Debian 10. We have a 42
GB file full of random bytes that we continually cat to /dev/null.
This fills the page cache as the file is read. Meanwhile we trigger
the balloon to inflate, with a target size of 53 GB. This setup causes
the balloon inflation to pressure the page cache as the page cache is
also trying to grow. Afterwards we shrink the balloon back to zero (so
total deflate = total inflate).

Without patch (kernel 4.19.0-5):
Inflation never reaches the target until we stop the "cat file >
/dev/null" process. Total inflation time was 542 seconds. The longest
period that made no net forward progress was 315 seconds (see attached
graph).
Result of "grep balloon /proc/vmstat" after the test:
balloon_inflate 154828377
balloon_deflate 154828377

With patch (kernel 5.6.0-rc4+):
Total inflation duration was 63 seconds. No deflate-queue activity
occurs when pressuring the page-cache.
Result of "grep balloon /proc/vmstat" after the test:
balloon_inflate 12968539
balloon_deflate 12968539

Conclusion: This patch fixes the issue. In the test it reduced
inflate/deflate activity by 12x, and reduced inflation time by 8.6x.
But more importantly, if we hadn't killed the "grep balloon
/proc/vmstat" process then, without the patch, the inflation process
would never reach the target.

Attached [1] is a png of a graph showing the problematic behavior without
this patch. It shows deflate-queue activity increasing linearly while
balloon size stays constant over the course of more than 8 minutes of
the test.

[1] https://lore.kernel.org/linux-mm/CAJuQAmphPcfew1v_EOgAdSFiprzjiZjmOf3iJDmFX0gD6b9TYQ@mail.gmail.com/2-without_patch.png

Full test report and discussion [2]:

[2] https://lore.kernel.org/r/CAJuQAmphPcfew1v_EOgAdSFiprzjiZjmOf3iJDmFX0gD6b9TYQ@mail.gmail.com

Tested-by: Tyler Sanderson <tysand@google.com>
Reported-by: Tyler Sanderson <tysand@google.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Wei Wang <wei.w.wang@intel.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200205163402.42627-4-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-03-23 09:50:02 -04:00
Nathan Chancellor 6ae4edab2f virtio_balloon: Adjust label in virtballoon_probe
Clang warns when CONFIG_BALLOON_COMPACTION is unset:

../drivers/virtio/virtio_balloon.c:963:1: warning: unused label
'out_del_vqs' [-Wunused-label]
out_del_vqs:
^~~~~~~~~~~~
1 warning generated.

Move the label within the preprocessor block since it is only used when
CONFIG_BALLOON_COMPACTION is set.

Fixes: 1ad6f58ea9 ("virtio_balloon: Fix memory leaks on errors in virtballoon_probe()")
Link: https://github.com/ClangBuiltLinux/linux/issues/886
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Link: https://lore.kernel.org/r/20200216004039.23464-1-natechancellor@gmail.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
2020-03-08 05:35:24 -04:00
Suman Anna f13f09a12c virtio_ring: Fix mem leak with vring_new_virtqueue()
The functions vring_new_virtqueue() and __vring_new_virtqueue() are used
with split rings, and any allocations within these functions are managed
outside of the .we_own_ring flag. The commit cbeedb72b9 ("virtio_ring:
allocate desc state for split ring separately") allocates the desc state
within the __vring_new_virtqueue() but frees it only when the .we_own_ring
flag is set. This leads to a memory leak when freeing such allocated
virtqueues with the vring_del_virtqueue() function.

Fix this by moving the desc_state free code outside the flag and only
for split rings. Issue was discovered during testing with remoteproc
and virtio_rpmsg.

Fixes: cbeedb72b9 ("virtio_ring: allocate desc state for split ring separately")
Signed-off-by: Suman Anna <s-anna@ti.com>
Link: https://lore.kernel.org/r/20200224212643.30672-1-s-anna@ti.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2020-03-08 05:35:23 -04:00
David Hildenbrand 1ad6f58ea9 virtio_balloon: Fix memory leaks on errors in virtballoon_probe()
We forget to put the inode and unmount the kernfs used for compaction.

Fixes: 71994620bb ("virtio_balloon: replace oom notifier with shrinker")
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Wei Wang <wei.w.wang@intel.com>
Cc: Liang Li <liang.z.li@intel.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200205163402.42627-3-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-02-06 03:40:27 -05:00
David Hildenbrand 6c22dc61c7 virtio-balloon: Fix memory leak when unloading while hinting is in progress
When unloading the driver while hinting is in progress, we will not
release the free page blocks back to MM, resulting in a memory leak.

Fixes: 86a559787e ("virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT")
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Wei Wang <wei.w.wang@intel.com>
Cc: Liang Li <liang.z.li@intel.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200205163402.42627-2-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-02-06 03:40:26 -05:00
Michael S. Tsirkin 6e9826e772 virtio_balloon: prevent pfn array overflow
Make sure, at build time, that pfn array is big enough to hold a single
page.  It happens to be true since the PAGE_SHIFT value at the moment is
20, which is 1M - exactly 256 4K balloon pages.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
2020-02-06 03:40:26 -05:00
Daniel Verkamp 303090b513 virtio-pci: check name when counting MSI-X vectors
VQs without a name specified are not valid; they are skipped in the
later loop that assigns MSI-X vectors to queues, but the per_vq_vectors
loop above that counts the required number of vectors previously still
counted any queue with a non-NULL callback as needing a vector.

Add a check to the per_vq_vectors loop so that vectors with no name are
not counted to make the two loops consistent.  This prevents
over-counting unnecessary vectors (e.g. for features which were not
negotiated with the device).

Cc: stable@vger.kernel.org
Fixes: 86a559787e ("virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT")
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Daniel Verkamp <dverkamp@chromium.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Wang, Wei W <wei.w.wang@intel.com>
2020-02-06 03:40:26 -05:00
Daniel Verkamp 5790b53390 virtio-balloon: initialize all vq callbacks
Ensure that elements of the callbacks array that correspond to
unavailable features are set to NULL; previously, they would be left
uninitialized.

Since the corresponding names array elements were explicitly set to
NULL, the uninitialized callback pointers would not actually be
dereferenced; however, the uninitialized callbacks elements would still
be read in vp_find_vqs_msix() and used to calculate the number of MSI-X
vectors required.

Cc: stable@vger.kernel.org
Fixes: 86a559787e ("virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT")
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Daniel Verkamp <dverkamp@chromium.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-02-06 03:40:26 -05:00
Yangtao Li c64eb62cfc virtio-mmio: convert to devm_platform_ioremap_resource
Use devm_platform_ioremap_resource() to simplify code, which
contains platform_get_resource, devm_request_mem_region and
devm_ioremap.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-02-06 03:40:26 -05:00
Michael S. Tsirkin 63b9b80e9f virtio_balloon: divide/multiply instead of shifts
We managed to get confused about the shift direction at least once.
Let's switch to division/multiplcation instead. Add a number of pages
macro for this purpose.  We still keep the order macro around too since
this is what alloc/free pages want.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Wei Wang <wei.w.wang@intel.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
2019-12-11 08:14:07 -05:00
Michael S. Tsirkin 2a946fa1c8 virtio_balloon: name cleanups
free_page_order is a confusing name. It's not a page order
actually, it's the order of the block of memory we are hinting.
Rename to hint_block_order. Also, rename SIZE to BYTES
to make it clear it's the block size in bytes.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Wei Wang <wei.w.wang@intel.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
2019-12-11 08:14:06 -05:00
David Hildenbrand 63341ab037 virtio-balloon: fix managed page counts when migrating pages between zones
In case we have to migrate a ballon page to a newpage of another zone, the
managed page count of both zones is wrong. Paired with memory offlining
(which will adjust the managed page count), we can trigger kernel crashes
and all kinds of different symptoms.

One way to reproduce:
1. Start a QEMU guest with 4GB, no NUMA
2. Hotplug a 1GB DIMM and online the memory to ZONE_NORMAL
3. Inflate the balloon to 1GB
4. Unplug the DIMM (be quick, otherwise unmovable data ends up on it)
5. Observe /proc/zoneinfo
  Node 0, zone   Normal
    pages free     16810
          min      24848885473806
          low      18471592959183339
          high     36918337032892872
          spanned  262144
          present  262144
          managed  18446744073709533486
6. Do anything that requires some memory (e.g., inflate the balloon some
more). The OOM goes crazy and the system crashes
  [  238.324946] Out of memory: Killed process 537 (login) total-vm:27584kB, anon-rss:860kB, file-rss:0kB, shmem-rss:00
  [  238.338585] systemd invoked oom-killer: gfp_mask=0x100cca(GFP_HIGHUSER_MOVABLE), order=0, oom_score_adj=0
  [  238.339420] CPU: 0 PID: 1 Comm: systemd Tainted: G      D W         5.4.0-next-20191204+ #75
  [  238.340139] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu4
  [  238.341121] Call Trace:
  [  238.341337]  dump_stack+0x8f/0xd0
  [  238.341630]  dump_header+0x61/0x5ea
  [  238.341942]  oom_kill_process.cold+0xb/0x10
  [  238.342299]  out_of_memory+0x24d/0x5a0
  [  238.342625]  __alloc_pages_slowpath+0xd12/0x1020
  [  238.343024]  __alloc_pages_nodemask+0x391/0x410
  [  238.343407]  pagecache_get_page+0xc3/0x3a0
  [  238.343757]  filemap_fault+0x804/0xc30
  [  238.344083]  ? ext4_filemap_fault+0x28/0x42
  [  238.344444]  ext4_filemap_fault+0x30/0x42
  [  238.344789]  __do_fault+0x37/0x1a0
  [  238.345087]  __handle_mm_fault+0x104d/0x1ab0
  [  238.345450]  handle_mm_fault+0x169/0x360
  [  238.345790]  do_user_addr_fault+0x20d/0x490
  [  238.346154]  do_page_fault+0x31/0x210
  [  238.346468]  async_page_fault+0x43/0x50
  [  238.346797] RIP: 0033:0x7f47eba4197e
  [  238.347110] Code: Bad RIP value.
  [  238.347387] RSP: 002b:00007ffd7c0c1890 EFLAGS: 00010293
  [  238.347834] RAX: 0000000000000002 RBX: 000055d196a20a20 RCX: 00007f47eba4197e
  [  238.348437] RDX: 0000000000000033 RSI: 00007ffd7c0c18c0 RDI: 0000000000000004
  [  238.349047] RBP: 00007ffd7c0c1c20 R08: 0000000000000000 R09: 0000000000000033
  [  238.349660] R10: 00000000ffffffff R11: 0000000000000293 R12: 0000000000000001
  [  238.350261] R13: ffffffffffffffff R14: 0000000000000000 R15: 00007ffd7c0c18c0
  [  238.350878] Mem-Info:
  [  238.351085] active_anon:3121 inactive_anon:51 isolated_anon:0
  [  238.351085]  active_file:12 inactive_file:7 isolated_file:0
  [  238.351085]  unevictable:0 dirty:0 writeback:0 unstable:0
  [  238.351085]  slab_reclaimable:5565 slab_unreclaimable:10170
  [  238.351085]  mapped:3 shmem:111 pagetables:155 bounce:0
  [  238.351085]  free:720717 free_pcp:2 free_cma:0
  [  238.353757] Node 0 active_anon:12484kB inactive_anon:204kB active_file:48kB inactive_file:28kB unevictable:0kB iss
  [  238.355979] Node 0 DMA free:11556kB min:36kB low:48kB high:60kB reserved_highatomic:0KB active_anon:152kB inactivB
  [  238.358345] lowmem_reserve[]: 0 2955 2884 2884 2884
  [  238.358761] Node 0 DMA32 free:2677864kB min:7004kB low:10028kB high:13052kB reserved_highatomic:0KB active_anon:0B
  [  238.361202] lowmem_reserve[]: 0 0 72057594037927865 72057594037927865 72057594037927865
  [  238.361888] Node 0 Normal free:193448kB min:99395541895224kB low:73886371836733356kB high:147673348131571488kB reB
  [  238.364765] lowmem_reserve[]: 0 0 0 0 0
  [  238.365101] Node 0 DMA: 7*4kB (U) 5*8kB (UE) 6*16kB (UME) 2*32kB (UM) 1*64kB (U) 2*128kB (UE) 3*256kB (UME) 2*512B
  [  238.366379] Node 0 DMA32: 0*4kB 1*8kB (U) 2*16kB (UM) 2*32kB (UM) 2*64kB (UM) 1*128kB (U) 1*256kB (U) 1*512kB (U)B
  [  238.367654] Node 0 Normal: 1985*4kB (UME) 1321*8kB (UME) 844*16kB (UME) 524*32kB (UME) 300*64kB (UME) 138*128kB (B
  [  238.369184] Node 0 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=2048kB
  [  238.369915] 130 total pagecache pages
  [  238.370241] 0 pages in swap cache
  [  238.370533] Swap cache stats: add 0, delete 0, find 0/0
  [  238.370981] Free swap  = 0kB
  [  238.371239] Total swap = 0kB
  [  238.371488] 1048445 pages RAM
  [  238.371756] 0 pages HighMem/MovableOnly
  [  238.372090] 306992 pages reserved
  [  238.372376] 0 pages cma reserved
  [  238.372661] 0 pages hwpoisoned

In another instance (older kernel), I was able to observe this
(negative page count :/):
  [  180.896971] Offlined Pages 32768
  [  182.667462] Offlined Pages 32768
  [  184.408117] Offlined Pages 32768
  [  186.026321] Offlined Pages 32768
  [  187.684861] Offlined Pages 32768
  [  189.227013] Offlined Pages 32768
  [  190.830303] Offlined Pages 32768
  [  190.833071] Built 1 zonelists, mobility grouping on.  Total pages: -36920272750453009

In another instance (older kernel), I was no longer able to start any
process:
  [root@vm ~]# [  214.348068] Offlined Pages 32768
  [  215.973009] Offlined Pages 32768
  cat /proc/meminfo
  -bash: fork: Cannot allocate memory
  [root@vm ~]# cat /proc/meminfo
  -bash: fork: Cannot allocate memory

Fix it by properly adjusting the managed page count when migrating if
the zone changed. The managed page count of the zones now looks after
unplug of the DIMM (and after deflating the balloon) just like before
inflating the balloon (and plugging+onlining the DIMM).

We'll temporarily modify the totalram page count. If this ever becomes a
problem, we can fine tune by providing helpers that don't touch
the totalram pages (e.g., adjust_zone_managed_page_count()).

Please note that fixing up the managed page count is only necessary when
we adjusted the managed page count when inflating - only if we
don't have VIRTIO_BALLOON_F_DEFLATE_ON_OOM. With that feature, the
managed page count is not touched when inflating/deflating.

Reported-by: Yumei Huang <yuhuang@redhat.com>
Fixes: 3dcc0571cd ("mm: correctly update zone->managed_pages")
Cc: <stable@vger.kernel.org> # v3.11+
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Jiang Liu <liuj97@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-12-11 08:14:06 -05:00
Wei Wang c9a6820fc0 virtio_balloon: fix shrinker count
Instead of multiplying by page order, virtio balloon divided by page
order. The result is that it can return 0 if there are a bit less
than MAX_ORDER - 1 pages in use, and then shrinker scan won't be called.

Cc: stable@vger.kernel.org
Fixes: 71994620bb ("virtio_balloon: replace oom notifier with shrinker")
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
2019-11-20 02:15:57 -05:00
Michael S. Tsirkin 60bd04f258 virtio_balloon: fix shrinker scan number of pages
virtio_balloon_shrinker_scan should return number of system pages freed,
but because it's calling functions that deal with balloon pages, it gets
confused and sometimes returns the number of balloon pages.

It does not matter practically as the exact number isn't
used, but it seems better to be consistent in case someone
starts using this API.

Further, if we ever tried to iteratively leak pages as
virtio_balloon_shrinker_scan tries to do, we'd run into issues - this is
because freed_pages was accumulating total freed pages, but was also
subtracted on each iteration from pages_to_free, which can result in
either leaking less memory than we were supposed to free, or more if
pages_to_free underruns.

On a system with 4K pages we are lucky that we are never asked to leak
more than 128 pages while we can leak up to 256 at a time,
but it looks like a real issue for systems with page size != 4K.

Fixes: 71994620bb ("virtio_balloon: replace oom notifier with shrinker")
Reported-by: Khazhismel Kumykov <khazhy@google.com>
Reviewed-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-11-20 02:15:57 -05:00
Halil Pasic f7728002c1 virtio_ring: fix return code on DMA mapping fails
Commit 780bc7903a ("virtio_ring: Support DMA APIs")  makes
virtqueue_add() return -EIO when we fail to map our I/O buffers. This is
a very realistic scenario for guests with encrypted memory, as swiotlb
may run out of space, depending on it's size and the I/O load.

The virtio-blk driver interprets -EIO form virtqueue_add() as an IO
error, despite the fact that swiotlb full is in absence of bugs a
recoverable condition.

Let us change the return code to -ENOMEM, and make the block layer
recover form these failures when virtio-blk encounters the condition
described above.

Cc: stable@vger.kernel.org
Fixes: 780bc7903a ("virtio_ring: Support DMA APIs")
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Tested-by: Michael Mueller <mimu@linux.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-11-19 05:13:49 -05:00
Marvin Liu 40ce7919d8 virtio_ring: fix stalls for packed rings
When VIRTIO_F_RING_EVENT_IDX is negotiated, virtio devices can
use virtqueue_enable_cb_delayed_packed to reduce the number of device
interrupts.  At the moment, this is the case for virtio-net when the
napi_tx module parameter is set to false.

In this case, the virtio driver selects an event offset and expects that
the device will send a notification when rolling over the event offset
in the ring.  However, if this roll-over happens before the event
suppression structure update, the notification won't be sent. To address
this race condition the driver needs to check wether the device rolled
over the offset after updating the event suppression structure.

With VIRTIO_F_RING_PACKED, the virtio driver did this by reading the
flags field of the descriptor at the specified offset.

Unfortunately, checking at the event offset isn't reliable: if
descriptors are chained (e.g. when INDIRECT is off) not all descriptors
are overwritten by the device, so it's possible that the device skipped
the specific descriptor driver is checking when writing out used
descriptors. If this happens, the driver won't detect the race condition
and will incorrectly expect the device to send a notification.

For virtio-net, the result will be a TX queue stall, with the
transmission getting blocked forever.

With the packed ring, it isn't easy to find a location which is
guaranteed to change upon the roll-over, except the next device
descriptor, as described in the spec:

        Writes of device and driver descriptors can generally be
        reordered, but each side (driver and device) are only required to
        poll (or test) a single location in memory: the next device descriptor after
        the one they processed previously, in circular order.

while this might be sub-optimal, let's do exactly this for now.

Cc: stable@vger.kernel.org
Cc: Jason Wang <jasowang@redhat.com>
Fixes: f51f982682 ("virtio_ring: leverage event idx in packed ring")
Signed-off-by: Marvin Liu <yong.liu@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-10-28 04:24:46 -04:00
Matthias Lange cf8f169670 virtio_ring: fix unmap of indirect descriptors
The function virtqueue_add_split() DMA-maps the scatterlist buffers. In
case a mapping error occurs the already mapped buffers must be unmapped.
This happens by jumping to the 'unmap_release' label.

In case of indirect descriptors the release is wrong and may leak kernel
memory. Because the implementation assumes that the head descriptor is
already mapped it starts iterating over the descriptor list starting
from the head descriptor. However for indirect descriptors the head
descriptor is never mapped in case of an error.

The fix is to initialize the start index with zero in case of indirect
descriptors and use the 'desc' pointer directly for iterating over the
descriptor chain.

Signed-off-by: Matthias Lange <matthias.lange@kernkonzept.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-09-09 10:43:15 -04:00
Linus Torvalds 933a90bf4f Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs mount updates from Al Viro:
 "The first part of mount updates.

  Convert filesystems to use the new mount API"

* 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  mnt_init(): call shmem_init() unconditionally
  constify ksys_mount() string arguments
  don't bother with registering rootfs
  init_rootfs(): don't bother with init_ramfs_fs()
  vfs: Convert smackfs to use the new mount API
  vfs: Convert selinuxfs to use the new mount API
  vfs: Convert securityfs to use the new mount API
  vfs: Convert apparmorfs to use the new mount API
  vfs: Convert openpromfs to use the new mount API
  vfs: Convert xenfs to use the new mount API
  vfs: Convert gadgetfs to use the new mount API
  vfs: Convert oprofilefs to use the new mount API
  vfs: Convert ibmasmfs to use the new mount API
  vfs: Convert qib_fs/ipathfs to use the new mount API
  vfs: Convert efivarfs to use the new mount API
  vfs: Convert configfs to use the new mount API
  vfs: Convert binfmt_misc to use the new mount API
  convenience helper: get_tree_single()
  convenience helper get_tree_nodev()
  vfs: Kill sget_userns()
  ...
2019-07-19 10:42:02 -07:00
Linus Torvalds f8c3500cd1 - virtio_pmem: The new virtio_pmem facility introduces a paravirtualized
persistent memory device that allows a guest VM to use DAX mechanisms to
   access a host-file with host-page-cache. It arranges for MAP_SYNC to
   be disabled and instead triggers a host fsync() when a 'write-cache
   flush' command is sent to the virtual disk device.
 
 - Miscellaneous small fixups.
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Merge tag 'libnvdimm-for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dan Williams:
 "Primarily just the virtio_pmem driver:

   - virtio_pmem

     The new virtio_pmem facility introduces a paravirtualized
     persistent memory device that allows a guest VM to use DAX
     mechanisms to access a host-file with host-page-cache. It arranges
     for MAP_SYNC to be disabled and instead triggers a host fsync()
     when a 'write-cache flush' command is sent to the virtual disk
     device.

   - Miscellaneous small fixups"

* tag 'libnvdimm-for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  virtio_pmem: fix sparse warning
  xfs: disable map_sync for async flush
  ext4: disable map_sync for async flush
  dax: check synchronous mapping is supported
  dm: enable synchronous dax
  libnvdimm: add dax_dev sync flag
  virtio-pmem: Add virtio pmem driver
  libnvdimm: nd_region flush callback support
  libnvdimm, namespace: Drop uuid_t implementation detail
2019-07-18 10:52:08 -07:00
Ihor Matushchak 5e663f0410 virtio-mmio: add error check for platform_get_irq
in vm_find_vqs() irq has a wrong type
so, in case of no IRQ resource defined,
wrong parameter will be passed to request_irq()

Signed-off-by: Ihor Matushchak <ihor.matushchak@foobox.net>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Ivan T. Ivanov <iivanov.xz@gmail.com>
2019-07-11 16:22:29 -04:00
Pankaj Gupta 6e84200c0a virtio-pmem: Add virtio pmem driver
This patch adds virtio-pmem driver for KVM guest.

Guest reads the persistent memory range information from
Qemu over VIRTIO and registers it on nvdimm_bus. It also
creates a nd_region object with the persistent memory
range information so that existing 'nvdimm/pmem' driver
can reserve this into system memory map. This way
'virtio-pmem' driver uses existing functionality of pmem
driver to register persistent memory compatible for DAX
capable filesystems.

This also provides function to perform guest flush over
VIRTIO from 'pmem' driver when userspace performs flush
on DAX memory range.

Signed-off-by: Pankaj Gupta <pagupta@redhat.com>
Reviewed-by: Yuval Shaia <yuval.shaia@oracle.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jakub Staron <jstaron@google.com>
Tested-by: Jakub Staron <jstaron@google.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2019-07-05 15:19:10 -07:00
Fabrizio Castro 6166e5330c virtio: Fix indentation of VIRTIO_MMIO
VIRTIO_MMIO config option block starts with a space, fix that.

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-05-27 11:08:22 -04:00
David Howells 99558d203c vfs: Convert virtio_balloon to use the new mount API
Convert the virtio_balloon filesystem to the new internal mount API as the old
one will be obsoleted and removed.  This allows greater flexibility in
communication of mount parameters between userspace, the VFS and the
filesystem.

See Documentation/filesystems/mount_api.txt for more information.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: "Michael S. Tsirkin" <mst@redhat.com>
cc: Jason Wang <jasowang@redhat.com>
cc: virtualization@lists.linux-foundation.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-05-25 18:06:15 -04:00
Al Viro 1f58bb18f6 mount_pseudo(): drop 'name' argument, switch to d_make_root()
Once upon a time we used to set ->d_name of e.g. pipefs root
so that d_path() on pipes would work.  These days it's
completely pointless - dentries of pipes are not even connected
to pipefs root.  However, mount_pseudo() had set the root
dentry name (passed as the second argument) and callers
kept inventing names to pass to it.  Including those that
didn't *have* any non-root dentries to start with...

All of that had been pointless for about 8 years now; it's
time to get rid of that cargo-culting...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-05-25 17:59:24 -04:00
Thomas Gleixner fd534e9b5f treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 102
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  51 franklin st fifth floor boston ma 02110 1301 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 50 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190523091649.499889647@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:39:00 +02:00
Thomas Gleixner f33f5fe256 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 78
Based on 1 normalized pattern(s):

  this work is licensed under the terms of the gnu gpl version 2 or
  later see the copying file in the top level directory

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 6 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520075210.858783702@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:37:51 +02:00
Thomas Gleixner ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Thomas Gleixner 09c434b8a0 treewide: Add SPDX license identifier for more missed files
Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have MODULE_LICENCE("GPL*") inside which was used in the initial
   scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:45 +02:00
Al Viro 985f404487 balloon: don't bother with dentry_operations
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-05-20 14:09:46 +01:00
Jiang Biao a5581206c5 virtio/virtio_ring: do some comment fixes
There are lots of mismatches between comments and codes, this
patch do these comment fixes.

Signed-off-by: Jiang Biao <benbjiang@tencent.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-05-12 13:11:35 -04:00
YueHaibing df0bfe7501 virtio_ring: Fix potential mem leak in virtqueue_add_indirect_packed
'desc' should be freed before leaving from err handing path.

Fixes: 1ce9e6055f ("virtio_ring: introduce packed ring support")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
stable@vger.kernel.org
2019-05-12 13:11:35 -04:00
Cornelia Huck cf94db2190 virtio: Honour 'may_reduce_num' in vring_create_virtqueue
vring_create_virtqueue() allows the caller to specify via the
may_reduce_num parameter whether the vring code is allowed to
allocate a smaller ring than specified.

However, the split ring allocation code tries to allocate a
smaller ring on allocation failure regardless of what the
caller specified. This may cause trouble for e.g. virtio-pci
in legacy mode, which does not support ring resizing. (The
packed ring code does not resize in any case.)

Let's fix this by bailing out immediately in the split ring code
if the requested size cannot be allocated and may_reduce_num has
not been specified.

While at it, fix a typo in the usage instructions.

Fixes: 2a2d1382fe ("virtio: Add improved queue allocation API")
Cc: stable@vger.kernel.org # v4.6+
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Jens Freimann <jfreimann@redhat.com>
2019-04-08 17:05:52 -04:00
Longpeng 6a8aae68c8 virtio_pci: fix a NULL pointer reference in vp_del_vqs
If the msix_affinity_masks is alloced failed, then we'll
try to free some resources in vp_free_vectors() that may
access it directly.

We met the following stack in our production:
[   29.296767] BUG: unable to handle kernel NULL pointer dereference at  (null)
[   29.311151] IP: [<ffffffffc04fe35a>] vp_free_vectors+0x6a/0x150 [virtio_pci]
[   29.324787] PGD 0
[   29.333224] Oops: 0000 [#1] SMP
[...]
[   29.425175] RIP: 0010:[<ffffffffc04fe35a>]  [<ffffffffc04fe35a>] vp_free_vectors+0x6a/0x150 [virtio_pci]
[   29.441405] RSP: 0018:ffff9a55c2dcfa10  EFLAGS: 00010206
[   29.453491] RAX: 0000000000000000 RBX: ffff9a55c322c400 RCX: 0000000000000000
[   29.467488] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff9a55c322c400
[   29.481461] RBP: ffff9a55c2dcfa20 R08: 0000000000000000 R09: ffffc1b6806ff020
[   29.495427] R10: 0000000000000e95 R11: 0000000000aaaaaa R12: 0000000000000000
[   29.509414] R13: 0000000000010000 R14: ffff9a55bd2d9e98 R15: ffff9a55c322c400
[   29.523407] FS:  00007fdcba69f8c0(0000) GS:ffff9a55c2840000(0000) knlGS:0000000000000000
[   29.538472] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   29.551621] CR2: 0000000000000000 CR3: 000000003ce52000 CR4: 00000000003607a0
[   29.565886] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   29.580055] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   29.594122] Call Trace:
[   29.603446]  [<ffffffffc04fe8a2>] vp_request_msix_vectors+0xe2/0x260 [virtio_pci]
[   29.618017]  [<ffffffffc04fedc5>] vp_try_to_find_vqs+0x95/0x3b0 [virtio_pci]
[   29.632152]  [<ffffffffc04ff117>] vp_find_vqs+0x37/0xb0 [virtio_pci]
[   29.645582]  [<ffffffffc057bf63>] init_vq+0x153/0x260 [virtio_blk]
[   29.658831]  [<ffffffffc057c1e8>] virtblk_probe+0xe8/0x87f [virtio_blk]
[...]

Cc: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: Longpeng <longpeng2@huawei.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Gonglei <arei.gonglei@huawei.com>
2019-04-08 08:40:58 -04:00
Cornelia Huck ab7a2375fb virtio: hint if callbacks surprisingly might sleep
A virtio transport is free to implement some of the callbacks in
virtio_config_ops in a matter that they cannot be called from
atomic context (e.g. virtio-ccw, which maps a lot of the callbacks
to channel I/O, which is an inherently asynchronous mechanism).
This can be very surprising for developers using the much more
common virtio-pci transport, just to find out that things break
when used on s390.

The documentation for virtio_config_ops now contains a comment
explaining this, but it makes sense to add a might_sleep() annotation
to various wrapper functions in the virtio core to avoid surprises
later.

Note that annotations are NOT added to two classes of calls:
- direct calls from device drivers (all current callers should be
  fine, however)
- calls which clearly won't be made from atomic context (such as
  those ultimately coming in via the driver core)

Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-03-06 11:19:57 -05:00
Wei Wang 59f3397ca7 virtio_balloon: remove the unnecessary 0-initialization
We've changed to kzalloc the vb struct, so no need to 0-initialize
this field one more time.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
2019-03-06 11:19:33 -05:00
Wei Wang 53e946cb34 virtio-balloon: improve update_balloon_size_func
There is no need to update the balloon actual register when there is no
ballooning request. This patch avoids update_balloon_size when diff is 0.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-03-06 11:19:33 -05:00
Joerg Roedel e6d6dd6c87 virtio: Introduce virtio_max_dma_size()
This function returns the maximum segment size for a single
dma transaction of a virtio device. The possible limit comes
from the SWIOTLB implementation in the Linux kernel, that
has an upper limit of (currently) 256kb of contiguous
memory it can map. Other DMA-API implementations might also
have limits.

Use the new dma_max_mapping_size() function to determine the
maximum mapping size when DMA-API is in use for virtio.

Cc: stable@vger.kernel.org
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-03-06 11:19:15 -05:00
Michael S. Tsirkin 9c0644ee4a virtio: drop internal struct from UAPI
There's no reason to expose struct vring_packed in UAPI - if we do we
won't be able to change or drop it, and it's not part of any interface.

Let's move it to virtio_ring.c

Cc: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-02-05 15:29:48 -05:00
Tiwei Bie 45383fb0f4 virtio: support VIRTIO_F_ORDER_PLATFORM
This patch introduces the support for VIRTIO_F_ORDER_PLATFORM.
If this feature is negotiated, the driver must use the barriers
suitable for hardware devices. Otherwise, the device and driver
are assumed to be implemented in software, that is they can be
assumed to run on identical CPUs in an SMP configuration. Thus
a weaker form of memory barriers is sufficient to yield better
performance.

It is recommended that an add-in card based PCI device offers
this feature for portability. The device will fail to operate
further or will operate in a slower emulation mode if this
feature is offered but not accepted.

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-01-24 10:15:42 -05:00
Wei Wang bf4dc0b2be virtio-balloon: tweak config_changed implementation
virtio-ccw has deadlock issues with reading the config space inside the
interrupt context, so we tweak the virtballoon_changed implementation
by moving the config read operations into the related workqueue contexts.
The config_read_bitmap is used as a flag to the workqueue callbacks
about the related config fields that need to be read.

The cmd_id_received is also renamed to cmd_id_received_cache, and
the value should be obtained via virtio_balloon_cmd_id_received.

Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 86a559787e ("virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT")
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
2019-01-14 20:15:20 -05:00
Wei Wang a229989d97 virtio: don't allocate vqs when names[i] = NULL
Some vqs may not need to be allocated when their related feature bits
are disabled. So callers may pass in such vqs with "names = NULL".
Then we skip such vq allocations.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 86a559787e ("virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT")
2019-01-14 20:15:19 -05:00
Wei Wang ddbeac07a3 virtio_pci: use queue idx instead of array idx to set up the vq
When find_vqs, there will be no vq[i] allocation if its corresponding
names[i] is NULL. For example, the caller may pass in names[i] (i=4)
with names[2] being NULL because the related feature bit is turned off,
so technically there are 3 queues on the device, and name[4] should
correspond to the 3rd queue on the device.

So we use queue_idx as the queue index, which is increased only when the
queue exists.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
2019-01-14 20:15:18 -05:00
Linus Torvalds d548e65904 virtio, vhost: features, fixes, cleanups
discard in virtio blk
 misc fixes and cleanups
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio/vhost updates from Michael Tsirkin:
"Features, fixes, cleanups:

   - discard in virtio blk

   - misc fixes and cleanups"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  vhost: correct the related warning message
  vhost: split structs into a separate header file
  virtio: remove deprecated VIRTIO_PCI_CONFIG()
  vhost/vsock: switch to a mutex for vhost_vsock_hash
  virtio_blk: add discard and write zeroes support
2019-01-02 18:54:45 -08:00
Dongli Zhang e8d26f29b7 virtio: remove deprecated VIRTIO_PCI_CONFIG()
VIRTIO_PCI_CONFIG() is deprecated. Use VIRTIO_PCI_CONFIG_OFF() instead.

Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-12-19 18:23:49 -05:00
Tiwei Bie f959a128fe virtio_ring: advertize packed ring layout
Advertize the packed ring layout support.

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-26 22:17:40 -08:00
Tiwei Bie f51f982682 virtio_ring: leverage event idx in packed ring
Leverage the EVENT_IDX feature in packed ring to suppress
events when it's available.

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-26 22:17:39 -08:00
Tiwei Bie 1ce9e6055f virtio_ring: introduce packed ring support
Introduce the packed ring support. Packed ring can only be
created by vring_create_virtqueue() and each chunk of packed
ring will be allocated individually. Packed ring can not be
created on preallocated memory by vring_new_virtqueue() or
the likes currently.

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-26 22:17:39 -08:00
Tiwei Bie fb3fba6b16 virtio_ring: cache whether we will use DMA API
Cache whether we will use DMA API, instead of doing the
check every time. We are going to check whether DMA API
is used more often in packed ring.

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-26 22:17:39 -08:00
Tiwei Bie d79dca75c7 virtio_ring: extract split ring handling from ring creation
Introduce a specific function to create the split ring.
And also move the DMA allocation and size information to
the .split sub-structure.

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-26 22:17:39 -08:00
Tiwei Bie cbeedb72b9 virtio_ring: allocate desc state for split ring separately
Put the split ring's desc state into the .split sub-structure,
and allocate desc state for split ring separately, this makes
the code more readable and more consistent with what we will
do for packed ring.

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-26 22:17:39 -08:00
Tiwei Bie 2f18c2d153 virtio_ring: introduce helper for indirect feature
Introduce a helper to check whether we will use indirect
feature. It will be used by packed ring too.

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-26 22:17:39 -08:00
Tiwei Bie 4d6a105eb5 virtio_ring: introduce debug helpers
Introduce debug helpers for last_add_time update, check and
invalid. They will be used by packed ring too.

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-26 22:17:39 -08:00
Tiwei Bie e593bf9751 virtio_ring: put split ring fields in a sub struct
Put the split ring specific fields in a sub-struct named
as "split" to avoid misuse after introducing packed ring.
There is no functional change.

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-26 22:17:39 -08:00
Tiwei Bie e6f633e5be virtio_ring: put split ring functions together
Put the xxx_split() functions together to make the
code more readable and avoid misuse after introducing
the packed ring. There is no functional change.

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-26 22:17:39 -08:00
Tiwei Bie 138fd25148 virtio_ring: add _split suffix for split ring functions
Add _split suffix for split ring specific functions. This
is a preparation for introducing the packed ring support.
There is no functional change.

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-26 22:17:39 -08:00
Wei Wang 2e991629bc virtio-balloon: VIRTIO_BALLOON_F_PAGE_POISON
The VIRTIO_BALLOON_F_PAGE_POISON feature bit is used to indicate if the
guest is using page poisoning. Guest writes to the poison_val config
field to tell host about the page poisoning value that is in use.

Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-10-24 20:57:55 -04:00
Wei Wang 86a559787e virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT
Negotiation of the VIRTIO_BALLOON_F_FREE_PAGE_HINT feature indicates the
support of reporting hints of guest free pages to host via virtio-balloon.
Currenlty, only free page blocks of MAX_ORDER - 1 are reported. They are
obtained one by one from the mm free list via the regular allocation
function.

Host requests the guest to report free page hints by sending a new cmd id
to the guest via the free_page_report_cmd_id configuration register. When
the guest starts to report, it first sends a start cmd to host via the
free page vq, which acks to host the cmd id received. When the guest
finishes reporting free pages, a stop cmd is sent to host via the vq.
Host may also send a stop cmd id to the guest to stop the reporting.

VIRTIO_BALLOON_CMD_ID_STOP: Host sends this cmd to stop the guest
reporting.
VIRTIO_BALLOON_CMD_ID_DONE: Host sends this cmd to tell the guest that
the reported pages are ready to be freed.

Why does the guest free the reported pages when host tells it is ready to
free?
This is because freeing pages appears to be expensive for live migration.
free_pages() dirties memory very quickly and makes the live migraion not
converge in some cases. So it is good to delay the free_page operation
when the migration is done, and host sends a command to guest about that.

Why do we need the new VIRTIO_BALLOON_CMD_ID_DONE, instead of reusing
VIRTIO_BALLOON_CMD_ID_STOP?
This is because live migration is usually done in several rounds. At the
end of each round, host needs to send a VIRTIO_BALLOON_CMD_ID_STOP cmd to
the guest to stop (or say pause) the reporting. The guest resumes the
reporting when it receives a new command id at the beginning of the next
round. So we need a new cmd id to distinguish between "stop reporting" and
"ready to free the reported pages".

TODO:
- Add a batch page allocation API to amortize the allocation overhead.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Liang Li <liang.z.li@intel.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-10-24 20:57:55 -04:00
Linus Torvalds d002924f93 virtio, vhost: fixes, tweaks
No new features but a bunch of tweaks such as
 switching balloon from oom notifier to shrinker.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio updates from Michael Tsirkin:
 "virtio, vhost: fixes, tweaks

  No new features but a bunch of tweaks such as switching balloon from
  oom notifier to shrinker"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  vhost/scsi: increase VHOST_SCSI_PREALLOC_PROT_SGLS to 2048
  vhost: allow vhost-scsi driver to be built-in
  virtio: pci-legacy: Validate queue pfn
  virtio: mmio-v1: Validate queue PFN
  virtio_balloon: replace oom notifier with shrinker
  virtio-balloon: kzalloc the vb struct
  virtio-balloon: remove BUG() in init_vqs
2018-08-24 08:45:19 -07:00
Suzuki K Poulose 69599206ea virtio: pci-legacy: Validate queue pfn
Legacy PCI over virtio uses a 32bit PFN for the queue. If the
queue pfn is too large to fit in 32bits, which we could hit on
arm64 systems with 52bit physical addresses (even with 64K page
size), we simply miss out a proper link to the other side of
the queue.

Add a check to validate the PFN, rather than silently breaking
the devices.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoffer Dall <cdall@kernel.org>
Cc: Peter Maydel <peter.maydell@linaro.org>
Cc: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-08-22 00:56:58 +03:00
Suzuki K Poulose 3fc92a96c2 virtio: mmio-v1: Validate queue PFN
virtio-mmio with virtio-v1 uses a 32bit PFN for the queue.
If the queue pfn is too large to fit in 32bits, which
we could hit on arm64 systems with 52bit physical addresses
(even with 64K page size), we simply miss out a proper link
to the other side of the queue.

Add a check to validate the PFN, rather than silently breaking
the devices.

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoffer Dall <cdall@kernel.org>
Cc: Peter Maydel <peter.maydell@linaro.org>
Cc: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-08-22 00:56:56 +03:00
Wei Wang 71994620bb virtio_balloon: replace oom notifier with shrinker
The OOM notifier is getting deprecated to use for the reasons:
- As a callout from the oom context, it is too subtle and easy to
  generate bugs and corner cases which are hard to track;
- It is called too late (after the reclaiming has been performed).
  Drivers with large amuont of reclaimable memory is expected to
  release them at an early stage of memory pressure;
- The notifier callback isn't aware of oom contrains;
Link: https://lkml.org/lkml/2018/7/12/314

This patch replaces the virtio-balloon oom notifier with a shrinker
to release balloon pages on memory pressure. The balloon pages are
given back to mm adaptively by returning the number of pages that the
reclaimer is asking for (i.e. sc->nr_to_scan).

Currently the max possible value of sc->nr_to_scan passed to the balloon
shrinker is SHRINK_BATCH, which is 128. This is smaller than the
limitation that only VIRTIO_BALLOON_ARRAY_PFNS_MAX (256) pages can be
returned via one invocation of leak_balloon. But this patch still
considers the case that SHRINK_BATCH or shrinker->batch could be changed
to a value larger than VIRTIO_BALLOON_ARRAY_PFNS_MAX, which will need to
do multiple invocations of leak_balloon.

Historically, the feature VIRTIO_BALLOON_F_DEFLATE_ON_OOM has been used
to release balloon pages on OOM. We continue to use this feature bit for
the shrinker, so the shrinker is only registered when this feature bit
has been negotiated with host.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-08-22 00:56:24 +03:00
Wei Wang c51d8fca0c virtio-balloon: kzalloc the vb struct
Zero all the vb fields at alloaction, so that we don't need to
zero-initialize each field one by one later.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-08-22 00:56:24 +03:00
Wei Wang 74cf5b169c virtio-balloon: remove BUG() in init_vqs
It's a bit overkill to use BUG when failing to add an entry to the
stats_vq in init_vqs. So remove it and just return the error to the
caller to bail out nicely.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-08-22 00:56:24 +03:00
Caleb Raitto 19e226e8cc virtio: Make vp_set_vq_affinity() take a mask.
Make vp_set_vq_affinity() take a cpumask instead of taking a single CPU.

If there are fewer queues than cores, queue affinity should be able to
map to multiple cores.

Link: https://patchwork.ozlabs.org/patch/948149/
Suggested-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Caleb Raitto <caraitto@google.com>
Acked-by: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-11 12:02:18 -07:00
Jiang Biao 89da619bc1 virtio_balloon: fix another race between migration and ballooning
Kernel panic when with high memory pressure, calltrace looks like,

PID: 21439 TASK: ffff881be3afedd0 CPU: 16 COMMAND: "java"
 #0 [ffff881ec7ed7630] machine_kexec at ffffffff81059beb
 #1 [ffff881ec7ed7690] __crash_kexec at ffffffff81105942
 #2 [ffff881ec7ed7760] crash_kexec at ffffffff81105a30
 #3 [ffff881ec7ed7778] oops_end at ffffffff816902c8
 #4 [ffff881ec7ed77a0] no_context at ffffffff8167ff46
 #5 [ffff881ec7ed77f0] __bad_area_nosemaphore at ffffffff8167ffdc
 #6 [ffff881ec7ed7838] __node_set at ffffffff81680300
 #7 [ffff881ec7ed7860] __do_page_fault at ffffffff8169320f
 #8 [ffff881ec7ed78c0] do_page_fault at ffffffff816932b5
 #9 [ffff881ec7ed78f0] page_fault at ffffffff8168f4c8
    [exception RIP: _raw_spin_lock_irqsave+47]
    RIP: ffffffff8168edef RSP: ffff881ec7ed79a8 RFLAGS: 00010046
    RAX: 0000000000000246 RBX: ffffea0019740d00 RCX: ffff881ec7ed7fd8
    RDX: 0000000000020000 RSI: 0000000000000016 RDI: 0000000000000008
    RBP: ffff881ec7ed79a8 R8: 0000000000000246 R9: 000000000001a098
    R10: ffff88107ffda000 R11: 0000000000000000 R12: 0000000000000000
    R13: 0000000000000008 R14: ffff881ec7ed7a80 R15: ffff881be3afedd0
    ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018

It happens in the pagefault and results in double pagefault
during compacting pages when memory allocation fails.

Analysed the vmcore, the page leads to second pagefault is corrupted
with _mapcount=-256, but private=0.

It's caused by the race between migration and ballooning, and lock
missing in virtballoon_migratepage() of virtio_balloon driver.
This patch fix the bug.

Fixes: e22504296d ("virtio_balloon: introduce migration primitives to balloon pages")
Cc: stable@vger.kernel.org
Signed-off-by: Jiang Biao <jiang.biao2@zte.com.cn>
Signed-off-by: Huang Chong <huang.chong@zte.com.cn>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-07-30 16:45:33 +03:00
Linus Torvalds 2f3f056685 virtio, vhost: features, fixes
VF support for virtio.
 DMA barriers for virtio strong barriers.
 Bugfixes.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio updates from Michael Tsirkin:
 "virtio, vhost: features, fixes

   - PCI virtual function support for virtio

   - DMA barriers for virtio strong barriers

   - bugfixes"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio: update the comments for transport features
  virtio_pci: support enabling VFs
  vhost: fix info leak due to uninitialized memory
  virtio_ring: switch to dma_XX barriers for rpmsg
2018-06-16 06:35:02 +09:00
Kees Cook 6396bb2215 treewide: kzalloc() -> kcalloc()
The kzalloc() function has a 2-factor argument form, kcalloc(). This
patch replaces cases of:

        kzalloc(a * b, gfp)

with:
        kcalloc(a * b, gfp)

as well as handling cases of:

        kzalloc(a * b * c, gfp)

with:

        kzalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kzalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kzalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kzalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kzalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kzalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kzalloc
+ kcalloc
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kzalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kzalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kzalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kzalloc(sizeof(THING) * C2, ...)
|
  kzalloc(sizeof(TYPE) * C2, ...)
|
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(C1 * C2, ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
Kees Cook 6da2ec5605 treewide: kmalloc() -> kmalloc_array()
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This
patch replaces cases of:

        kmalloc(a * b, gfp)

with:
        kmalloc_array(a * b, gfp)

as well as handling cases of:

        kmalloc(a * b * c, gfp)

with:

        kmalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kmalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kmalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The tools/ directory was manually excluded, since it has its own
implementation of kmalloc().

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kmalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kmalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kmalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kmalloc
+ kmalloc_array
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kmalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kmalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kmalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kmalloc(sizeof(THING) * C2, ...)
|
  kmalloc(sizeof(TYPE) * C2, ...)
|
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(C1 * C2, ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
Tiwei Bie cfecc2918d virtio_pci: support enabling VFs
There is a new feature bit allocated in virtio spec to
support SR-IOV (Single Root I/O Virtualization):

https://github.com/oasis-tcs/virtio-spec/issues/11

This patch enables the support for this feature bit in
virtio driver.

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-06-12 04:59:29 +03:00
Linus Torvalds e241e3f2bf virtio: feature
This adds reporting hugepage stats to virtio-balloon.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio update from Michael Tsirkin:
 "This adds reporting hugepage stats to virtio-balloon"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio_balloon: export hugetlb page allocation counts
2018-04-11 18:58:27 -07:00
Jonathan Helman 6c64fe7f2a virtio_balloon: export hugetlb page allocation counts
Export the number of successful and failed hugetlb page
allocations via the virtio balloon driver. These 2 counts
come directly from the vm_events HTLB_BUDDY_PGALLOC and
HTLB_BUDDY_PGALLOC_FAIL.

Signed-off-by: Jonathan Helman <jonathan.helman@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
2018-04-10 21:23:55 +03:00
Randy Dunlap 514c603249 headers: untangle kmemleak.h from mm.h
Currently <linux/slab.h> #includes <linux/kmemleak.h> for no obvious
reason.  It looks like it's only a convenience, so remove kmemleak.h
from slab.h and add <linux/kmemleak.h> to any users of kmemleak_* that
don't already #include it.  Also remove <linux/kmemleak.h> from source
files that do not use it.

This is tested on i386 allmodconfig and x86_64 allmodconfig.  It would
be good to run it through the 0day bot for other $ARCHes.  I have
neither the horsepower nor the storage space for the other $ARCHes.

Update: This patch has been extensively build-tested by both the 0day
bot & kisskb/ozlabs build farms.  Both of them reported 2 build failures
for which patches are included here (in v2).

[ slab.h is the second most used header file after module.h; kernel.h is
  right there with slab.h. There could be some minor error in the
  counting due to some #includes having comments after them and I didn't
  combine all of those. ]

[akpm@linux-foundation.org: security/keys/big_key.c needs vmalloc.h, per sfr]
Link: http://lkml.kernel.org/r/e4309f98-3749-93e1-4bb7-d9501a39d015@infradead.org
Link: http://kisskb.ellerman.id.au/kisskb/head/13396/
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Reported-by: Michael Ellerman <mpe@ellerman.id.au>	[2 build failures]
Reported-by: Fengguang Wu <fengguang.wu@intel.com>	[2 build failures]
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Wei Yongjun <weiyongjun1@huawei.com>
Cc: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: John Johansen <john.johansen@canonical.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05 21:36:27 -07:00
Tiwei Bie e82df67023 virtio_ring: fix num_free handling in error case
The vq->vq.num_free hasn't been changed when error happens,
so it shouldn't be changed when handling the error.

Fixes: 780bc7903a ("virtio_ring: Support DMA APIs")
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-01 18:53:38 +02:00
weiping zhang 33635bd976 virtio_pci: don't kfree device on register failure
As mentioned at drivers/base/core.c:
/*
 * NOTE: _Never_ directly free @dev after calling this function, even
 * if it returned an error! Always use put_device() to give up the
 * reference initialized in this function instead.
 */
so we don't free vp_dev until vp_dev->vdev.dev.release be called.

Signed-off-by: weiping zhang <zhangweiping@didichuxing.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-02-01 16:26:45 +02:00
weiping zhang f2b44cde7e virtio: split device_register into device_initialize and device_add
In order to make caller do a simple cleanup, we split device_register
into device_initialize and device_add. device_initialize always succeeds,
so the caller can always use put_device when register_virtio_device faild.

Signed-off-by: weiping zhang <zhangweiping@didichuxing.com>
Suggested-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
2018-02-01 16:26:45 +02:00
Vincent Legoll 7b95fec6d2 virtio: make VIRTIO a menuconfig to ease disabling it all
No need to get into the submenu to disable all VIRTIO-related
config entries.

This makes it easier to disable all VIRTIO config options
without entering the submenu. It will also enable one
to see that en/dis-abled state from the outside menu.

This is only intended to change menuconfig UI, not change
the config dependencies.

Signed-off-by: Vincent Legoll <vincent.legoll@gmail.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-02-01 16:26:43 +02:00
Arvind Yadav 31919140ff virtio: virtio_mmio: make of_device_ids const.
of_device_ids are not supposed to change at runtime. All functions
working with of_device_ids provided by <linux/of.h> work with const
of_device_ids. So mark the non-const structs as const.

File size before:
   text	   data	    bss	    dec	    hex	filename
   3647	    608	      0	   4255	   109f	drivers/virtio/virtio_mmio.o

File size after constify virtio_mmio_match.
   text	   data	    bss	    dec	    hex	filename
   4063	    192	      0	   4255	   109f	drivers/virtio/virtio_mmio.o

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-01-31 01:47:35 +02:00
Vasyl Gomonovych c2c9f9bc5b virtio-mmio: Use PTR_ERR_OR_ZERO()
Fix ptr_ret.cocci warnings:
drivers/virtio/virtio_mmio.c:653:1-3: WARNING: PTR_ERR_OR_ZERO can be used

Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR

Generated by: scripts/coccinelle/api/ptr_ret.cocci

Signed-off-by: Vasyl Gomonovych <gomonovych@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-01-31 01:47:34 +02:00
Tomáš Golembiovský 4d32029b8d virtio_balloon: include disk/file caches memory statistics
Add a new field VIRTIO_BALLOON_S_CACHES to virtio_balloon memory
statistics protocol. The value represents all disk/file caches.

In this case it corresponds to the sum of values
Buffers+Cached+SwapCached from /proc/meminfo.

Signed-off-by: Tomáš Golembiovský <tgolembi@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-01-31 01:47:33 +02:00
Mark Rutland c2e90800ae virtio_mmio: fix devm cleanup
Recent rework of the virtio_mmio probe/remove paths balanced a
devm_ioremap() with an iounmap() rather than its devm variant. This ends
up corrupting the devm datastructures, and results in the following
boot-time splat on arm64 under QEMU 2.9.0:

[    3.450397] ------------[ cut here ]------------
[    3.453822] Trying to vfree() nonexistent vm area (00000000c05b4844)
[    3.460534] WARNING: CPU: 1 PID: 1 at mm/vmalloc.c:1525 __vunmap+0x1b8/0x220
[    3.475898] Kernel panic - not syncing: panic_on_warn set ...
[    3.475898]
[    3.493933] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.15.0-rc3 #1
[    3.513109] Hardware name: linux,dummy-virt (DT)
[    3.525382] Call trace:
[    3.531683]  dump_backtrace+0x0/0x368
[    3.543921]  show_stack+0x20/0x30
[    3.547767]  dump_stack+0x108/0x164
[    3.559584]  panic+0x25c/0x51c
[    3.569184]  __warn+0x29c/0x31c
[    3.576023]  report_bug+0x1d4/0x290
[    3.586069]  bug_handler.part.2+0x40/0x100
[    3.597820]  bug_handler+0x4c/0x88
[    3.608400]  brk_handler+0x11c/0x218
[    3.613430]  do_debug_exception+0xe8/0x318
[    3.627370]  el1_dbg+0x18/0x78
[    3.634037]  __vunmap+0x1b8/0x220
[    3.648747]  vunmap+0x6c/0xc0
[    3.653864]  __iounmap+0x44/0x58
[    3.659771]  devm_ioremap_release+0x34/0x68
[    3.672983]  release_nodes+0x404/0x880
[    3.683543]  devres_release_all+0x6c/0xe8
[    3.695692]  driver_probe_device+0x250/0x828
[    3.706187]  __driver_attach+0x190/0x210
[    3.717645]  bus_for_each_dev+0x14c/0x1f0
[    3.728633]  driver_attach+0x48/0x78
[    3.740249]  bus_add_driver+0x26c/0x5b8
[    3.752248]  driver_register+0x16c/0x398
[    3.757211]  __platform_driver_register+0xd8/0x128
[    3.770860]  virtio_mmio_init+0x1c/0x24
[    3.782671]  do_one_initcall+0xe0/0x398
[    3.791890]  kernel_init_freeable+0x594/0x660
[    3.798514]  kernel_init+0x18/0x190
[    3.810220]  ret_from_fork+0x10/0x18

To fix this, we can simply rip out the explicit cleanup that the devm
infrastructure will do for us when our probe function returns an error
code, or when our remove function returns.

We only need to ensure that we call put_device() if a call to
register_virtio_device() fails in the probe path.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Fixes: 7eb781b1bb ("virtio_mmio: add cleanup for virtio_mmio_probe")
Fixes: 25f32223bc ("virtio_mmio: add cleanup for virtio_mmio_remove")
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: weiping zhang <zhangweiping@didichuxing.com>
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
2017-12-14 21:01:40 +02:00
weiping zhang 25f32223bc virtio_mmio: add cleanup for virtio_mmio_remove
cleanup all resource allocated by virtio_mmio_probe.

Signed-off-by: weiping zhang <zhangweiping@didichuxing.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
2017-12-07 18:30:50 +02:00
weiping zhang 7eb781b1bb virtio_mmio: add cleanup for virtio_mmio_probe
As mentioned at drivers/base/core.c:
/*
 * NOTE: _Never_ directly free @dev after calling this function, even
 * if it returned an error! Always use put_device() to give up the
 * reference initialized in this function instead.
 */
so we don't free vm_dev until vm_dev.dev.release be called.

Signed-off-by: weiping zhang <zhangweiping@didichuxing.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
2017-12-07 18:30:50 +02:00
Jan Stancek d9e427f6ab virtio_balloon: fix increment of vb->num_pfns in fill_balloon()
commit c7cdff0e86 ("virtio_balloon: fix deadlock on OOM")
changed code to increment vb->num_pfns before call to
set_page_pfns(), which used to happen only after.

This patch fixes boot hang for me on ppc64le KVM guests.

Fixes: c7cdff0e86 ("virtio_balloon: fix deadlock on OOM")
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Wei Wang <wei.w.wang@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-12-01 16:55:45 +02:00
weiping zhang e60ea67bb6 virtio: release virtio index when fail to device_register
index can be reused by other virtio device.

Cc: stable@vger.kernel.org
Signed-off-by: weiping zhang <zhangweiping@didichuxing.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-12-01 16:55:32 +02:00
Michael S. Tsirkin c7cdff0e86 virtio_balloon: fix deadlock on OOM
fill_balloon doing memory allocations under balloon_lock
can cause a deadlock when leak_balloon is called from
virtballoon_oom_notify and tries to take same lock.

To fix, split page allocation and enqueue and do allocations outside the lock.

Here's a detailed analysis of the deadlock by Tetsuo Handa:

In leak_balloon(), mutex_lock(&vb->balloon_lock) is called in order to
serialize against fill_balloon(). But in fill_balloon(),
alloc_page(GFP_HIGHUSER[_MOVABLE] | __GFP_NOMEMALLOC | __GFP_NORETRY) is
called with vb->balloon_lock mutex held. Since GFP_HIGHUSER[_MOVABLE]
implies __GFP_DIRECT_RECLAIM | __GFP_IO | __GFP_FS, despite __GFP_NORETRY
is specified, this allocation attempt might indirectly depend on somebody
else's __GFP_DIRECT_RECLAIM memory allocation. And such indirect
__GFP_DIRECT_RECLAIM memory allocation might call leak_balloon() via
virtballoon_oom_notify() via blocking_notifier_call_chain() callback via
out_of_memory() when it reached __alloc_pages_may_oom() and held oom_lock
mutex. Since vb->balloon_lock mutex is already held by fill_balloon(), it
will cause OOM lockup.

  Thread1                                       Thread2
    fill_balloon()
      takes a balloon_lock
      balloon_page_enqueue()
        alloc_page(GFP_HIGHUSER_MOVABLE)
          direct reclaim (__GFP_FS context)       takes a fs lock
            waits for that fs lock                  alloc_page(GFP_NOFS)
                                                      __alloc_pages_may_oom()
                                                        takes the oom_lock
                                                        out_of_memory()
                                                          blocking_notifier_call_chain()
                                                            leak_balloon()
                                                              tries to take that balloon_lock and deadlocks

Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-11-14 23:57:38 +02:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Linus Torvalds 572c01ba19 SCSI misc on 20170907
This is mostly updates of the usual suspects: lpfc, qla2xxx, hisi_sas, megaraid_sas, zfcp and a host of minor updates.
 
 The major driver change here is the elimination of the block based
 cciss driver in favour of the SCSI based hpsa driver (which now drives
 all the legacy cases cciss used to be required for).  Plus a reset
 handler clean up and the redo of the SAS SMP handler to use bsg lib.
 
 Signed-off-by: James E.J. Bottomley <jejb@linux.vnet.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI updates from James Bottomley:
 "This is mostly updates of the usual suspects: lpfc, qla2xxx, hisi_sas,
  megaraid_sas, zfcp and a host of minor updates.

  The major driver change here is the elimination of the block based
  cciss driver in favour of the SCSI based hpsa driver (which now drives
  all the legacy cases cciss used to be required for). Plus a reset
  handler clean up and the redo of the SAS SMP handler to use bsg lib"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (279 commits)
  scsi: scsi-mq: Always unprepare before requeuing a request
  scsi: Show .retries and .jiffies_at_alloc in debugfs
  scsi: Improve requeuing behavior
  scsi: Call scsi_initialize_rq() for filesystem requests
  scsi: qla2xxx: Reset the logo flag, after target re-login.
  scsi: qla2xxx: Fix slow mem alloc behind lock
  scsi: qla2xxx: Clear fc4f_nvme flag
  scsi: qla2xxx: add missing includes for qla_isr
  scsi: qla2xxx: Fix an integer overflow in sysfs code
  scsi: aacraid: report -ENOMEM to upper layer from aac_convert_sgraw2()
  scsi: aacraid: get rid of one level of indentation
  scsi: aacraid: fix indentation errors
  scsi: storvsc: fix memory leak on ring buffer busy
  scsi: scsi_transport_sas: switch to bsg-lib for SMP passthrough
  scsi: smartpqi: remove the smp_handler stub
  scsi: hpsa: remove the smp_handler stub
  scsi: bsg-lib: pass the release callback through bsg_setup_queue
  scsi: Rework handling of scsi_device.vpd_pg8[03]
  scsi: Rework the code for caching Vital Product Data (VPD)
  scsi: rcu: Introduce rcu_swap_protected()
  ...
2017-09-07 21:11:05 -07:00
Linus Torvalds aae3dbb477 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) Support ipv6 checksum offload in sunvnet driver, from Shannon
    Nelson.

 2) Move to RB-tree instead of custom AVL code in inetpeer, from Eric
    Dumazet.

 3) Allow generic XDP to work on virtual devices, from John Fastabend.

 4) Add bpf device maps and XDP_REDIRECT, which can be used to build
    arbitrary switching frameworks using XDP. From John Fastabend.

 5) Remove UFO offloads from the tree, gave us little other than bugs.

 6) Remove the IPSEC flow cache, from Florian Westphal.

 7) Support ipv6 route offload in mlxsw driver.

 8) Support VF representors in bnxt_en, from Sathya Perla.

 9) Add support for forward error correction modes to ethtool, from
    Vidya Sagar Ravipati.

10) Add time filter for packet scheduler action dumping, from Jamal Hadi
    Salim.

11) Extend the zerocopy sendmsg() used by virtio and tap to regular
    sockets via MSG_ZEROCOPY. From Willem de Bruijn.

12) Significantly rework value tracking in the BPF verifier, from Edward
    Cree.

13) Add new jump instructions to eBPF, from Daniel Borkmann.

14) Rework rtnetlink plumbing so that operations can be run without
    taking the RTNL semaphore. From Florian Westphal.

15) Support XDP in tap driver, from Jason Wang.

16) Add 32-bit eBPF JIT for ARM, from Shubham Bansal.

17) Add Huawei hinic ethernet driver.

18) Allow to report MD5 keys in TCP inet_diag dumps, from Ivan
    Delalande.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1780 commits)
  i40e: point wb_desc at the nvm_wb_desc during i40e_read_nvm_aq
  i40e: avoid NVM acquire deadlock during NVM update
  drivers: net: xgene: Remove return statement from void function
  drivers: net: xgene: Configure tx/rx delay for ACPI
  drivers: net: xgene: Read tx/rx delay for ACPI
  rocker: fix kcalloc parameter order
  rds: Fix non-atomic operation on shared flag variable
  net: sched: don't use GFP_KERNEL under spin lock
  vhost_net: correctly check tx avail during rx busy polling
  net: mdio-mux: add mdio_mux parameter to mdio_mux_init()
  rxrpc: Make service connection lookup always check for retry
  net: stmmac: Delete dead code for MDIO registration
  gianfar: Fix Tx flow control deactivation
  cxgb4: Ignore MPS_TX_INT_CAUSE[Bubble] for T6
  cxgb4: Fix pause frame count in t4_get_port_stats
  cxgb4: fix memory leak
  tun: rename generic_xdp to skb_xdp
  tun: reserve extra headroom only when XDP is set
  net: dsa: bcm_sf2: Configure IMP port TC2QOS mapping
  net: dsa: bcm_sf2: Advertise number of egress queues
  ...
2017-09-06 14:45:08 -07:00
Linus Torvalds b0c79f49c3 Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm updates from Ingo Molnar:

 - Introduce the ORC unwinder, which can be enabled via
   CONFIG_ORC_UNWINDER=y.

   The ORC unwinder is a lightweight, Linux kernel specific debuginfo
   implementation, which aims to be DWARF done right for unwinding.
   Objtool is used to generate the ORC unwinder tables during build, so
   the data format is flexible and kernel internal: there's no
   dependency on debuginfo created by an external toolchain.

   The ORC unwinder is almost two orders of magnitude faster than the
   (out of tree) DWARF unwinder - which is important for perf call graph
   profiling. It is also significantly simpler and is coded defensively:
   there has not been a single ORC related kernel crash so far, even
   with early versions. (knock on wood!)

   But the main advantage is that enabling the ORC unwinder allows
   CONFIG_FRAME_POINTERS to be turned off - which speeds up the kernel
   measurably:

   With frame pointers disabled, GCC does not have to add frame pointer
   instrumentation code to every function in the kernel. The kernel's
   .text size decreases by about 3.2%, resulting in better cache
   utilization and fewer instructions executed, resulting in a broad
   kernel-wide speedup. Average speedup of system calls should be
   roughly in the 1-3% range - measurements by Mel Gorman [1] have shown
   a speedup of 5-10% for some function execution intense workloads.

   The main cost of the unwinder is that the unwinder data has to be
   stored in RAM: the memory cost is 2-4MB of RAM, depending on kernel
   config - which is a modest cost on modern x86 systems.

   Given how young the ORC unwinder code is it's not enabled by default
   - but given the performance advantages the plan is to eventually make
   it the default unwinder on x86.

   See Documentation/x86/orc-unwinder.txt for more details.

 - Remove lguest support: its intended role was that of a temporary
   proof of concept for virtualization, plus its removal will enable the
   reduction (removal) of the paravirt API as well, so Rusty agreed to
   its removal. (Juergen Gross)

 - Clean up and fix FSGS related functionality (Andy Lutomirski)

 - Clean up IO access APIs (Andy Shevchenko)

 - Enhance the symbol namespace (Jiri Slaby)

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (47 commits)
  objtool: Handle GCC stack pointer adjustment bug
  x86/entry/64: Use ENTRY() instead of ALIGN+GLOBAL for stub32_clone()
  x86/fpu/math-emu: Add ENDPROC to functions
  x86/boot/64: Extract efi_pe_entry() from startup_64()
  x86/boot/32: Extract efi_pe_entry() from startup_32()
  x86/lguest: Remove lguest support
  x86/paravirt/xen: Remove xen_patch()
  objtool: Fix objtool fallthrough detection with function padding
  x86/xen/64: Fix the reported SS and CS in SYSCALL
  objtool: Track DRAP separately from callee-saved registers
  objtool: Fix validate_branch() return codes
  x86: Clarify/fix no-op barriers for text_poke_bp()
  x86/switch_to/64: Rewrite FS/GS switching yet again to fix AMD CPUs
  selftests/x86/fsgsbase: Test selectors 1, 2, and 3
  x86/fsgsbase/64: Report FSBASE and GSBASE correctly in core dumps
  x86/fsgsbase/64: Fully initialize FS and GS state in start_thread_common
  x86/asm: Fix UNWIND_HINT_REGS macro for older binutils
  x86/asm/32: Fix regs_get_register() on segment registers
  x86/xen/64: Rearrange the SYSCALL entries
  x86/asm/32: Remove a bunch of '& 0xffff' from pt_regs segment reads
  ...
2017-09-04 09:52:57 -07:00
David S. Miller 6026e043d0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Three cases of simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-01 17:42:05 -07:00
Christoph Hellwig ba74b6f7fc virtio_pci: fix cpu affinity support
Commit 0b0f9dc5 ("Revert "virtio_pci: use shared interrupts for
virtqueues"") removed the adjustment of the pre_vectors for the virtio
MSI-X vector allocation which was added in commit fb5e31d9 ("virtio:
allow drivers to request IRQ affinity when creating VQs"). This will
lead to an incorrect assignment of MSI-X vectors, and potential
deadlocks when offlining cpus.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Fixes: 0b0f9dc5 ("Revert "virtio_pci: use shared interrupts for virtqueues")
Reported-by: YASUAKI ISHIMATSU <yasu.isimatu@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-08-25 21:38:26 +03:00
Richard W.M. Jones 44ed8089e9 scsi: virtio: Reduce BUG if total_sg > virtqueue size to WARN.
If using indirect descriptors, you can make the total_sg as large as you
want.  If not, BUG is too serious because the function later returns
-ENOSPC.

Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-24 22:28:51 -04:00
Juergen Gross ecda85e702 x86/lguest: Remove lguest support
Lguest seems to be rather unused these days. It has seen only patches
ensuring it still builds the last two years and its official state is
"Odd Fixes".

Remove it in order to be able to clean up the paravirt code.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: boris.ostrovsky@oracle.com
Cc: lguest@lists.ozlabs.org
Cc: rusty@rustcorp.com.au
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/20170816173157.8633-3-jgross@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-24 09:57:28 +02:00
David S. Miller 29fda25a2d Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Two minor conflicts in virtio_net driver (bug fix overlapping addition
of a helper) and MAINTAINERS (new driver edit overlapping revamp of
PHY entry).

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-01 10:07:50 -07:00
Wei Wang f9aada5fff virtio-balloon: coding format cleanup
Clean up the comment format.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-07-25 16:37:35 +03:00
Liang Li 195a8c43e9 virtio-balloon: deflate via a page list
This patch saves the deflated pages to a list, instead of the PFN array.
Accordingly, the balloon_pfn_to_page() function is removed.

Signed-off-by: Liang Li <liang.z.li@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-07-25 16:37:35 +03:00
Jason Wang 87646a348e virtio_ring: allow to store zero as the ctx
Allow zero to be store as a ctx, with this we could store e.g zero
value which could be meaningful for the case of storing headroom
through ctx.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-24 13:37:00 -07:00
Michael S. Tsirkin e41b135550 virtio_balloon: disable VIOMMU support
virtio balloon bypasses the DMA API entirely so does not support the
VIOMMU right now.  It's not clear we need that support, for now let's
just make sure we don't pretend to support it.

Cc: stable@vger.kernel.org
Cc: Wei Wang <wei.w.wang@intel.com>
Fixes: 1a93769399 ("virtio: new feature to detect IOMMU device quirk")
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2017-06-18 23:13:35 +03:00
Michael S. Tsirkin 5a08b04f63 virtio: allow extra context per descriptor
Allow extra context per descriptor. To avoid slow down for data path,
this disables use of indirect descriptors for this vq.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-02 23:41:43 +03:00
Michael S. Tsirkin f94682dde5 virtio: add context flag to find vqs
Allows maintaining extra context per vq.  For ease of use, passing in
NULL is legal and disables the feature for all vqs.

Includes fixes by Christian for s390, acked by Cornelia.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-02 23:41:43 +03:00
Michael S. Tsirkin 9b2bbdb227 virtio: wrap find_vqs
We are going to add more parameters to find_vqs, let's wrap the call so
we don't need to tweak all drivers every time.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-02 23:41:42 +03:00
Marc Zyngier 2f8dc3a01f virtio-pci: Remove affinity hint before freeing the interrupt
virtio-pci registers a per-vq affinity hint when using MSIX,
but fails to remove it when freeing the interrupt, resulting
in this type of splat:

[   31.111202] WARNING: CPU: 0 PID: 2823 at kernel/irq/manage.c:1503 __free_irq+0x2c4/0x2c8
[   31.114689] Modules linked in:
[   31.116101] CPU: 0 PID: 2823 Comm: kexec Not tainted 4.10.0+ #6941
[   31.118911] Hardware name: Generic DT based system
[   31.121319] [<c022fb78>] (unwind_backtrace) from [<c0229d8c>] (show_stack+0x18/0x1c)
[   31.125017] [<c0229d8c>] (show_stack) from [<c05192f4>] (dump_stack+0x84/0x98)
[   31.128427] [<c05192f4>] (dump_stack) from [<c023d940>] (__warn+0xf4/0x10c)
[   31.131910] [<c023d940>] (__warn) from [<c023da20>] (warn_slowpath_null+0x28/0x30)
[   31.135543] [<c023da20>] (warn_slowpath_null) from [<c0290238>] (__free_irq+0x2c4/0x2c8)
[   31.139355] [<c0290238>] (__free_irq) from [<c02902d0>] (free_irq+0x44/0x78)
[   31.142909] [<c02902d0>] (free_irq) from [<c059d3a8>] (vp_del_vqs+0x68/0x1c0)
[   31.146299] [<c059d3a8>] (vp_del_vqs) from [<c056ca4c>] (pci_device_shutdown+0x3c/0x78)

The obvious fix is to drop the affinity hint before freeing the
interrupt.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-04-11 00:30:20 +03:00
Michael S. Tsirkin 0a9b3f47da Revert "virtio_pci: remove struct virtio_pci_vq_info"
This reverts commit 5c34d002dc.

Conflicts:
	drivers/virtio/virtio_pci_common.c

The cleanup seems to be one of the changes that broke
hybernation for some users. We are still not sure why
but revert helps.

This reverts the cleanup changes but keeps the affinity support.

Tested-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-04-11 00:29:59 +03:00
Michael S. Tsirkin 0b0f9dc52e Revert "virtio_pci: use shared interrupts for virtqueues"
This reverts commit 07ec51480b.

Conflicts:
	drivers/virtio/virtio_pci_common.c

Unfortunately the idea does not work with threadirqs
as more than 32 queues can then map to a single interrupts.

Further, the cleanup seems to be one of the changes that broke
hybernation for some users. We are still not sure why
but revert helps.

This reverts the cleanup changes but keeps the affinity support.

Tested-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-04-11 00:28:57 +03:00
Michael S. Tsirkin 2008c1544c Revert "virtio_pci: don't duplicate the msix_enable flag in struct pci_dev"
This reverts commit 53a020c661.

The cleanup seems to be one of the changes that broke
hybernation for some users. We are still not sure why
but revert helps.

Tested-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-04-11 00:28:41 +03:00
Michael S. Tsirkin bf951b1045 Revert "virtio_pci: simplify MSI-X setup"
This reverts commit 52a6151612.

Conflicts:
	drivers/virtio/virtio_pci_common.c

The cleanup seems to be one of the changes that broke
hybernation for some users. We are still not sure why
but revert helps.

This reverts the cleanup changes but keeps the affinity support.

Tested-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-04-11 00:19:40 +03:00
Michael S. Tsirkin 8f10d0149f Revert "virtio_pci: fix out of bound access for msix_names"
This reverts commit de85ec8b07.

Follow-up patches will revert 07ec51480b ("virtio_pci: use shared
interrupts for virtqueues") that triggered the problem so no need for
this one anymore.

Tested-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-04-10 23:27:50 +03:00
Michael S. Tsirkin 404123c2db virtio: allow drivers to validate features
Some drivers can't support all features in all configurations.  At the
moment we blindly set FEATURES_OK and later FAILED.  Support this better
by adding a callback drivers can use to do some early checks.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-04-07 16:38:59 +03:00
Arnd Bergmann f0bb2d50df virtio_balloon: prevent uninitialized variable use
The latest gcc-7.0.1 snapshot reports a new warning:

virtio/virtio_balloon.c: In function 'update_balloon_stats':
virtio/virtio_balloon.c:258:26: error: 'events[2]' is used uninitialized in this function [-Werror=uninitialized]
virtio/virtio_balloon.c:260:26: error: 'events[3]' is used uninitialized in this function [-Werror=uninitialized]
virtio/virtio_balloon.c:261:56: error: 'events[18]' is used uninitialized in this function [-Werror=uninitialized]
virtio/virtio_balloon.c:262:56: error: 'events[17]' is used uninitialized in this function [-Werror=uninitialized]

This seems absolutely right, so we should add an extra check to
prevent copying uninitialized stack data into the statistics.
>From all I can tell, this has been broken since the statistics code
was originally added in 2.6.34.

Fixes: 9564e138b1 ("virtio: Add memory statistics reporting to the balloon driver (V4)")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-03-28 20:41:28 +03:00
Ladi Prosek 9646b26e85 virtio-balloon: use actual number of stats for stats queue buffers
The virtio balloon driver contained a not-so-obvious invariant that
update_balloon_stats has to update exactly VIRTIO_BALLOON_S_NR counters
in order to send valid stats to the host. This commit fixes it by having
update_balloon_stats return the actual number of counters, and its
callers use it when pushing buffers to the stats virtqueue.

Note that it is still out of spec to change the number of counters
at run-time. "Driver MUST supply the same subset of statistics in all
buffers submitted to the statsq."

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-03-28 20:41:28 +03:00
Ladi Prosek fc8653228c virtio_balloon: init 1st buffer in stats vq
When init_vqs runs, virtio_balloon.stats is either uninitialized or
contains stale values. The host updates its state with garbage data
because it has no way of knowing that this is just a marker buffer
used for signaling.

This patch updates the stats before pushing the initial buffer.

Alternative fixes:
* Push an empty buffer in init_vqs. Not easily done with the current
  virtio implementation and violates the spec "Driver MUST supply the
  same subset of statistics in all buffers submitted to the statsq".
* Push a buffer with invalid tags in init_vqs. Violates the same
  spec clause, plus "invalid tag" is not really defined.

Note: the spec says:
	When using the legacy interface, the device SHOULD ignore all values in
	the first buffer in the statsq supplied by the driver after device
	initialization. Note: Historically, drivers supplied an uninitialized
	buffer in the first buffer.

Unfortunately QEMU does not seem to implement the recommendation
even for the legacy interface.

Cc: stable@vger.kernel.org
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-03-28 20:41:27 +03:00
Jason Wang de85ec8b07 virtio_pci: fix out of bound access for msix_names
Fedora has received multiple reports of crashes when running
4.11 as a guest

https://bugzilla.redhat.com/show_bug.cgi?id=1430297
https://bugzilla.redhat.com/show_bug.cgi?id=1434462
https://bugzilla.kernel.org/show_bug.cgi?id=194911
https://bugzilla.redhat.com/show_bug.cgi?id=1433899

The crashes are not always consistent but they are generally
some flavor of oops or GPF in virtio related code. Multiple people
have done bisections (Thank you Thorsten Leemhuis and
Richard W.M. Jones) and found this commit to be at fault

07ec51480b is the first bad commit
commit 07ec51480b
Author: Christoph Hellwig <hch@lst.de>
Date:   Sun Feb 5 18:15:19 2017 +0100

    virtio_pci: use shared interrupts for virtqueues

The issue seems to be an out of bounds access to the msix_names
array corrupting kernel memory.

Fixes: 07ec51480b ("virtio_pci: use shared interrupts for virtqueues")
Reported-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Tested-by: Thorsten Leemhuis <linux@leemhuis.info>
2017-03-28 20:40:53 +03:00
Linus Torvalds 1827adb11a Merge branch 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull sched.h split-up from Ingo Molnar:
 "The point of these changes is to significantly reduce the
  <linux/sched.h> header footprint, to speed up the kernel build and to
  have a cleaner header structure.

  After these changes the new <linux/sched.h>'s typical preprocessed
  size goes down from a previous ~0.68 MB (~22K lines) to ~0.45 MB (~15K
  lines), which is around 40% faster to build on typical configs.

  Not much changed from the last version (-v2) posted three weeks ago: I
  eliminated quirks, backmerged fixes plus I rebased it to an upstream
  SHA1 from yesterday that includes most changes queued up in -next plus
  all sched.h changes that were pending from Andrew.

  I've re-tested the series both on x86 and on cross-arch defconfigs,
  and did a bisectability test at a number of random points.

  I tried to test as many build configurations as possible, but some
  build breakage is probably still left - but it should be mostly
  limited to architectures that have no cross-compiler binaries
  available on kernel.org, and non-default configurations"

* 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (146 commits)
  sched/headers: Clean up <linux/sched.h>
  sched/headers: Remove #ifdefs from <linux/sched.h>
  sched/headers: Remove the <linux/topology.h> include from <linux/sched.h>
  sched/headers, hrtimer: Remove the <linux/wait.h> include from <linux/hrtimer.h>
  sched/headers, x86/apic: Remove the <linux/pm.h> header inclusion from <asm/apic.h>
  sched/headers, timers: Remove the <linux/sysctl.h> include from <linux/timer.h>
  sched/headers: Remove <linux/magic.h> from <linux/sched/task_stack.h>
  sched/headers: Remove <linux/sched.h> from <linux/sched/init.h>
  sched/core: Remove unused prefetch_stack()
  sched/headers: Remove <linux/rculist.h> from <linux/sched.h>
  sched/headers: Remove the 'init_pid_ns' prototype from <linux/sched.h>
  sched/headers: Remove <linux/signal.h> from <linux/sched.h>
  sched/headers: Remove <linux/rwsem.h> from <linux/sched.h>
  sched/headers: Remove the runqueue_is_locked() prototype
  sched/headers: Remove <linux/sched.h> from <linux/sched/hotplug.h>
  sched/headers: Remove <linux/sched.h> from <linux/sched/debug.h>
  sched/headers: Remove <linux/sched.h> from <linux/sched/nohz.h>
  sched/headers: Remove <linux/sched.h> from <linux/sched/stat.h>
  sched/headers: Remove the <linux/gfp.h> include from <linux/sched.h>
  sched/headers: Remove <linux/rtmutex.h> from <linux/sched.h>
  ...
2017-03-03 10:16:38 -08:00
Linus Torvalds 54d7989f47 virtio, vhost: optimizations, fixes
Looks like a quiet cycle for vhost/virtio, just a couple of minor
 tweaks. Most notable is automatic interrupt affinity for blk and scsi.
 Hopefully other devices are not far behind.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull vhost updates from Michael Tsirkin:
 "virtio, vhost: optimizations, fixes

  Looks like a quiet cycle for vhost/virtio, just a couple of minor
  tweaks. Most notable is automatic interrupt affinity for blk and scsi.
  Hopefully other devices are not far behind"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio-console: avoid DMA from stack
  vhost: introduce O(1) vq metadata cache
  virtio_scsi: use virtio IRQ affinity
  virtio_blk: use virtio IRQ affinity
  blk-mq: provide a default queue mapping for virtio device
  virtio: provide a method to get the IRQ affinity mask for a virtqueue
  virtio: allow drivers to request IRQ affinity when creating VQs
  virtio_pci: simplify MSI-X setup
  virtio_pci: don't duplicate the msix_enable flag in struct pci_dev
  virtio_pci: use shared interrupts for virtqueues
  virtio_pci: remove struct virtio_pci_vq_info
  vhost: try avoiding avail index access when getting descriptor
  virtio_mmio: expose header to userspace
2017-03-02 13:53:13 -08:00
Ingo Molnar 50d34394ce sched/headers: Prepare to remove the <linux/magic.h> include from <linux/sched/task_stack.h>
Update files that depend on the magic.h inclusion.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:40 +01:00
Christoph Hellwig bbaba47956 virtio: provide a method to get the IRQ affinity mask for a virtqueue
This basically passed up the pci_irq_get_affinity information through
virtio through an optional get_vq_affinity method.  It is only implemented
by the PCI backend for now, and only when we use per-virtqueue IRQs.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-27 20:54:05 +02:00
Christoph Hellwig fb5e31d970 virtio: allow drivers to request IRQ affinity when creating VQs
Add a struct irq_affinity pointer to the find_vqs methods, which if set
is used to tell the PCI layer to create the MSI-X vectors for our I/O
virtqueues with the proper affinity from the start.  Compared to after
the fact affinity hints this gives us an instantly working setup and
allows to allocate the irq descritors node-local and avoid interconnect
traffic.  Last but not least this will allow blk-mq queues are created
based on the interrupt affinity for storage drivers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-27 20:54:04 +02:00
Christoph Hellwig 52a6151612 virtio_pci: simplify MSI-X setup
Try to grab the MSI-X vectors early and fall back to the shared one
before doing lots of allocations.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-27 20:54:04 +02:00
Christoph Hellwig 53a020c661 virtio_pci: don't duplicate the msix_enable flag in struct pci_dev
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-27 20:54:03 +02:00
Christoph Hellwig 07ec51480b virtio_pci: use shared interrupts for virtqueues
This lets IRQ layer handle dispatching IRQs to separate handlers for the
case where we don't have per-VQ MSI-X vectors, and allows us to greatly
simplify the code based on the assumption that we always have interrupt
vector 0 (legacy INTx or config interrupt for MSI-X) available, and
any other interrupt is request/freed throught the VQ, even if the
actual interrupt line might be shared in some cases.

This allows removing a great deal of variables keeping track of the
interrupt state in struct virtio_pci_device, as we can now simply walk the
list of VQs and deal with per-VQ interrupt handlers there, and only treat
vector 0 special.

Additionally clean up the VQ allocation code to properly unwind on error
instead of having a single global cleanup label, which is error prone,
and in this case also leads to more code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-27 20:54:03 +02:00
Christoph Hellwig 5c34d002dc virtio_pci: remove struct virtio_pci_vq_info
We don't really need struct virtio_pci_vq_info, as most field in there
are redundant:

 - the vq backpointer is not strictly neede to start with
 - the entry in the vqs list is not needed - the generic virtqueue already
   has list, we only need to check if it has a callback to get the same
   semantics
 - we can use a simple array to look up the MSI-X vec if needed.
 - That simple array now also duoble serves to replace the per_vq_vectors
   flag

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-27 20:54:03 +02:00
Michael S. Tsirkin 51be7a9a26 virtio_mmio: expose header to userspace
It's handy for userspace emulators like QEMU.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-27 16:31:23 +02:00
Yisheng Xie 9c57b5808c mm balloon: umount balloon_mnt when removing vb device
With CONFIG_BALLOON_COMPACTION=y the kernel will mount balloon_mnt for
balloon page migration when we probe a virtio_balloon device.  However
we do not unmount it when removing the device.  Fix this.

Fixes: b1123ea6d3 ("mm: balloon: use general non-lru movable page feature")
Link: http://lkml.kernel.org/r/1486531318-35189-1-git-send-email-xieyisheng1@huawei.com
Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Rafael Aquini <aquini@redhat.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Gioh Kim <gi-oh.kim@profitbricks.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:56 -08:00
David S. Miller 3efa70d78f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
The conflict was an interaction between a bug fix in the
netvsc driver in 'net' and an optimization of the RX path
in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-07 16:29:30 -05:00
John Fastabend 9fe7bfce8b virtio_net: refactor freeze/restore logic into virtnet reset logic
For XDP we will need to reset the queues to allow for buffer headroom
to be configured. In order to do this we need to essentially run the
freeze()/restore() code path. Unfortunately the locking requirements
between the freeze/restore and reset paths are different however so
we can not simply reuse the code.

This patch refactors the code path and adds a reset helper routine.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-07 10:05:12 -05:00
Michael S. Tsirkin 0d5415b489 Revert "vring: Force use of DMA API for ARM-based systems with legacy devices"
This reverts commit c7070619f3.

This has been shown to regress on some ARM systems:

by forcing on DMA API usage for ARM systems, we have inadvertently
kicked open a hornets' nest in terms of cache-coherency. Namely that
unless the virtio device is explicitly described as capable of coherent
DMA by firmware, the DMA APIs on ARM and other DT-based platforms will
assume it is non-coherent. This turns out to cause a big problem for the
likes of QEMU and kvmtool, which generate virtio-mmio devices in their
guest DTs but neglect to add the often-overlooked "dma-coherent"
property; as a result, we end up with the guest making non-cacheable
accesses to the vring, the host doing so cacheably, both talking past
each other and things going horribly wrong.

We are working on a safer work-around.

Fixes: c7070619f3 ("vring: Force use of DMA API for ARM-based systems with legacy devices")
Reported-by: Robin Murphy <robin.murphy@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-03 23:38:50 +02:00
Will Deacon c7070619f3 vring: Force use of DMA API for ARM-based systems with legacy devices
Booting Linux on an ARM fastmodel containing an SMMU emulation results
in an unexpected I/O page fault from the legacy virtio-blk PCI device:

[    1.211721] arm-smmu-v3 2b400000.smmu: event 0x10 received:
[    1.211800] arm-smmu-v3 2b400000.smmu:	0x00000000fffff010
[    1.211880] arm-smmu-v3 2b400000.smmu:	0x0000020800000000
[    1.211959] arm-smmu-v3 2b400000.smmu:	0x00000008fa081002
[    1.212075] arm-smmu-v3 2b400000.smmu:	0x0000000000000000
[    1.212155] arm-smmu-v3 2b400000.smmu: event 0x10 received:
[    1.212234] arm-smmu-v3 2b400000.smmu:	0x00000000fffff010
[    1.212314] arm-smmu-v3 2b400000.smmu:	0x0000020800000000
[    1.212394] arm-smmu-v3 2b400000.smmu:	0x00000008fa081000
[    1.212471] arm-smmu-v3 2b400000.smmu:	0x0000000000000000

<system hangs failing to read partition table>

This is because the legacy virtio-blk device is behind an SMMU, so we
have consequently swizzled its DMA ops and configured the SMMU to
translate accesses. This then requires the vring code to use the DMA API
to establish translations, otherwise all transactions will result in
fatal faults and termination.

Given that ARM-based systems only see an SMMU if one is really present
(the topology is all described by firmware tables such as device-tree or
IORT), then we can safely use the DMA API for all legacy virtio devices.
Modern devices can advertise the prescense of an IOMMU using the
VIRTIO_F_IOMMU_PLATFORM feature flag.

Cc: Andy Lutomirski <luto@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: <stable@vger.kernel.org>
Fixes: 876945dbf6 ("arm64: Hook up IOMMU dma_ops")
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
2017-01-25 00:33:11 +02:00
Robin Murphy f7f6634d23 virtio_mmio: Set DMA masks appropriately
Once DMA API usage is enabled, it becomes apparent that virtio-mmio is
inadvertently relying on the default 32-bit DMA mask, which leads to
problems like rapidly exhausting SWIOTLB bounce buffers.

Ensure that we set the appropriate 64-bit DMA mask whenever possible,
with the coherent mask suitably limited for the legacy vring as per
a0be1db430 ("virtio_pci: Limit DMA mask to 44 bits for legacy virtio
devices").

Cc: Andy Lutomirski <luto@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Reported-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Fixes: b42111382f ("virtio_mmio: Use the DMA API if enabled")
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-01-25 00:33:10 +02:00
Yuan Liu cecdbdc377 virtio_mmio: Set dev.release() to avoid warning
Fix a warning thrown from virtio_mmio_remove():
Device 'virtio0' does not have a release() function

The fix is according to virtio_pci_probe() of
drivers/virtio/virtio_pci_common.c

Signed-off-by: Yuan Liu <liuyuan@google.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-12-16 00:13:39 +02:00
Felipe Franciosi 0c7eaf5930 virtio_ring: fix description of virtqueue_get_buf
The device (not the driver) populates the used ring and includes the len
of how much data was written.

Signed-off-by: Felipe Franciosi <felipe@nutanix.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-12-16 00:13:38 +02:00
Christoph Hellwig a3cbec6972 virtio_pci: split vp_try_to_find_vqs into INTx and MSI-X variants
There is basically no shared logic between the INTx and MSI-X case in
vp_try_to_find_vqs, so split the function into two and clean them up
a little bit.

Also remove the fairly pointless vp_request_intx wrapper while we're at it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-12-16 00:12:49 +02:00
Christoph Hellwig 66f2f55542 virtio_pci: merge vp_free_vectors into vp_del_vqs
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-12-16 00:12:48 +02:00
Christoph Hellwig 9f8196cc05 virtio_pci: remove the call to vp_free_vectors in vp_request_msix_vectors
vp_request_msix_vectors is only called by vp_try_to_find_vqs, which already
calls vp_free_vectors through vp_del_vqs in the failure case.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-12-16 00:12:48 +02:00
Christoph Hellwig fa3a327935 virtio_pci: use pci_alloc_irq_vectors
This avoids the separate allocation for the msix_entries structures, and
instead allows us to use pci_irq_vector to find a given IRQ vector.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-12-16 00:12:47 +02:00
Michael S. Tsirkin d41795978c virtio: clean up handling of request_irq failure
We call del_vqs twice when request_irq fails, this
makes no sense.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-12-16 00:12:44 +02:00
Gonglei c60923cb9c virtio_ring: fix complaint by sparse
# make C=2 CF="-D__CHECK_ENDIAN__" ./drivers/virtio/

drivers/virtio/virtio_ring.c:423:19: warning: incorrect type in assignment (different base types)
drivers/virtio/virtio_ring.c:423:19:    expected unsigned int [unsigned] [assigned] i
drivers/virtio/virtio_ring.c:423:19:    got restricted __virtio16 [usertype] next
drivers/virtio/virtio_ring.c:423:19: warning: incorrect type in assignment (different base types)
drivers/virtio/virtio_ring.c:423:19:    expected unsigned int [unsigned] [assigned] i
drivers/virtio/virtio_ring.c:423:19:    got restricted __virtio16 [usertype] next
drivers/virtio/virtio_ring.c:423:19: warning: incorrect type in assignment (different base types)
drivers/virtio/virtio_ring.c:423:19:    expected unsigned int [unsigned] [assigned] i
drivers/virtio/virtio_ring.c:423:19:    got restricted __virtio16 [usertype] next
drivers/virtio/virtio_ring.c:604:39: warning: incorrect type in initializer (different base types)
drivers/virtio/virtio_ring.c:604:39:    expected unsigned short [unsigned] [usertype] nextflag
drivers/virtio/virtio_ring.c:604:39:    got restricted __virtio16
drivers/virtio/virtio_ring.c:612:33: warning: restricted __virtio16 degrades to integer

Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-12-15 06:39:47 +02:00
Gonglei 61bd405f4e virtio_pci_modern: fix complaint by sparse
drivers/virtio/virtio_pci_modern.c:66:40: warning: incorrect type in argument 2 (different base types)
drivers/virtio/virtio_pci_modern.c:66:40:    expected unsigned int [noderef] [usertype] <asn:2>*addr
drivers/virtio/virtio_pci_modern.c:66:40:    got restricted __le32 [noderef] [usertype] <asn:2>*lo
drivers/virtio/virtio_pci_modern.c:67:33: warning: incorrect type in argument 2 (different base types)
drivers/virtio/virtio_pci_modern.c:67:33:    expected unsigned int [noderef] [usertype] <asn:2>*addr
drivers/virtio/virtio_pci_modern.c:67:33:    got restricted __le32 [noderef] [usertype] <asn:2>*hi
drivers/virtio/virtio_pci_modern.c:150:32: warning: incorrect type in argument 2 (different base types)
drivers/virtio/virtio_pci_modern.c:150:32:    expected unsigned int [noderef] [usertype] <asn:2>*addr
drivers/virtio/virtio_pci_modern.c:150:32:    got restricted __le32 [noderef] <asn:2>*<noident>
drivers/virtio/virtio_pci_modern.c:151:39: warning: incorrect type in argument 1 (different base types)
drivers/virtio/virtio_pci_modern.c:151:39:    expected unsigned int [noderef] [usertype] <asn:2>*addr
drivers/virtio/virtio_pci_modern.c:151:39:    got restricted __le32 [noderef] <asn:2>*<noident>
drivers/virtio/virtio_pci_modern.c:152:32: warning: incorrect type in argument 2 (different base types)
drivers/virtio/virtio_pci_modern.c:152:32:    expected unsigned int [noderef] [usertype] <asn:2>*addr

Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-12-15 06:39:46 +02:00
Jonathan Corbet 917fef6f7e Linux 4.9-rc4
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Merge tag 'v4.9-rc4' into sound

Bring in -rc4 patches so I can successfully merge the sound doc changes.
2016-11-18 16:13:41 -07:00
Michael S. Tsirkin 75bfa81bf0 virtio_ring: mark vring_dma_dev inline
This inline function is unused on configurations
where dma_map/unmap are empty macros.

Make the function inline to avoid gcc errors because
of an unused static function.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-31 00:40:08 +02:00
Juergen Gross 3dae2c6152 virtio: remove config.c
Remove unused file config.c

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-31 00:21:45 +02:00
Konstantin Neumoin 8424af5336 virtio: update balloon size in balloon "probe"
The following commit 'fad7b7b27b6a (virtio_balloon: Use a workqueue
instead of "vballoon" kthread)' has added a regression. Original code with
kthread starts the thread inside probe and checks the necessity to update
balloon inside the thread immediately.

Nowadays the code behaves differently. Work is queued only on the first
command from the host after the negotiation. Thus there is a window
especially at the guest startup or the module reloading when the balloon
size is not updated until the notification from the host.

This patch adds balloon size check at the end of the probe to match
original behaviour.

Signed-off-by: Konstantin Neumoin <kneumoin@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-31 00:21:41 +02:00
Ladi Prosek 0ea1e4a6d9 virtio_ring: Make interrupt suppression spec compliant
According to the spec, if the VIRTIO_RING_F_EVENT_IDX feature bit is
negotiated the driver MUST set flags to 0. Not dirtying the available
ring in virtqueue_disable_cb also has a minor positive performance
impact, improving L1 dcache load missed by ~0.5% in vring_bench.

Writes to the used event field (vring_used_event) are still unconditional.

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: <stable@vger.kernel.org> # f277ec4 virtio_ring: shadow available
Cc: <stable@vger.kernel.org>
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-31 00:21:40 +02:00
Will Deacon a0be1db430 virtio_pci: Limit DMA mask to 44 bits for legacy virtio devices
Legacy virtio defines the virtqueue base using a 32-bit PFN field, with
a read-only register indicating a fixed page size of 4k.

This can cause problems for DMA allocators that allocate top down from
the DMA mask, which is set to 64 bits. In this case, the addresses are
silently truncated to 44-bit, leading to IOMMU faults, failure to read
from the queue or data corruption.

This patch restricts the coherent DMA mask for legacy PCI virtio devices
to 44 bits, which matches the specification.

Cc: stable@vger.kernel.org
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Benjamin Serebrin <serebrin@google.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-10-31 00:21:39 +02:00
Mauro Carvalho Chehab 8c27ceff36 docs: fix locations of several documents that got moved
The previous patch renamed several files that are cross-referenced
along the Kernel documentation. Adjust the links to point to
the right places.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2016-10-24 08:12:35 -02:00
Baoyou Xie af7c1beccf virtio: mark vring_dma_dev() static
We get 1 warning when building kernel with W=1:
drivers/virtio/virtio_ring.c:170:16: warning: no previous prototype for 'vring_dma_dev' [-Wmissing-prototypes]

In fact, this function is only used in the file in which it is
declared and don't need a declaration, but can be made static.
so this patch marks this function with 'static'.

Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-09-09 21:12:35 +03:00
Michael S. Tsirkin 3cc36f6e34 virtio: fix error handling for debug builds
On error, virtqueue_add calls START_USE but not
END_USE. Thankfully that's normally empty anyway,
but might not be when debugging. Fix it up.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-08-09 13:42:35 +03:00
Wei Yongjun 58625edf9e virtio: fix memory leak in virtqueue_add()
When using the indirect buffers feature, 'desc' is allocated in
virtqueue_add() but isn't freed before leaving on a ring full error,
causing a memory leak.

For example, it seems rather clear that this can trigger
with virtio net if mergeable buffers are not used.

Cc: stable@vger.kernel.org
Signed-off-by: Wei Yongjun <weiyj.lk@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-08-09 13:42:34 +03:00
Linus Torvalds 0803e04011 virtio/vhost: new features for 4.8
- New vsock device support in host and guest
 - Platform IOMMU support in host and guest,
   including compatibility quirks for legacy systems.
 - Misc fixes and cleanups.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio/vhost updates from Michael Tsirkin:

 - new vsock device support in host and guest

 - platform IOMMU support in host and guest, including compatibility
   quirks for legacy systems.

 - misc fixes and cleanups.

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  VSOCK: Use kvfree()
  vhost: split out vringh Kconfig
  vhost: detect 32 bit integer wrap around
  vhost: new device IOTLB API
  vhost: drop vringh dependency
  vhost: convert pre sorted vhost memory array to interval tree
  vhost: introduce vhost memory accessors
  VSOCK: Add Makefile and Kconfig
  VSOCK: Introduce vhost_vsock.ko
  VSOCK: Introduce virtio_transport.ko
  VSOCK: Introduce virtio_vsock_common.ko
  VSOCK: defer sock removal to transports
  VSOCK: transport-specific vsock_transport functions
  vhost: drop vringh dependency
  vop: pull in vhost Kconfig
  virtio: new feature to detect IOMMU device quirk
  balloon: check the number of available pages in leak balloon
  vhost: lockless enqueuing
  vhost: simplify work flushing
2016-08-06 09:20:13 -04:00
Michael S. Tsirkin 1a93769399 virtio: new feature to detect IOMMU device quirk
The interaction between virtio and IOMMUs is messy.

On most systems with virtio, physical addresses match bus addresses,
and it doesn't particularly matter which one we use to program
the device.

On some systems, including Xen and any system with a physical device
that speaks virtio behind a physical IOMMU, we must program the IOMMU
for virtio DMA to work at all.

On other systems, including SPARC and PPC64, virtio-pci devices are
enumerated as though they are behind an IOMMU, but the virtio host
ignores the IOMMU, so we must either pretend that the IOMMU isn't
there or somehow map everything as the identity.

Add a feature bit to detect that quirk: VIRTIO_F_IOMMU_PLATFORM.

Any device with this feature bit set to 0 needs a quirk and has to be
passed physical addresses (as opposed to bus addresses) even though
the device is behind an IOMMU.

Note: it has to be a per-device quirk because for example, there could
be a mix of passed-through and virtual virtio devices. As another
example, some devices could be implemented by an out of process
hypervisor backend (in case of qemu vhost, or vhost-user) and so support
for an IOMMU needs to be coded up separately.

It would be cleanest to handle this in IOMMU core code, but that needs
per-device DMA ops. While we are waiting for that to be implemented, use
a work-around in virtio core.

Note: a "noiommu" feature is a quirk - add a wrapper to make
that clear.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-08-01 21:44:52 +03:00
Konstantin Neumoin 37cf99e08c balloon: check the number of available pages in leak balloon
The balloon has a special mechanism that is subscribed to the oom
notification which leads to deflation for a fixed number of pages.
The number is always fixed even when the balloon is fully deflated.
But leak_balloon did not expect that the pages to deflate will be more
than taken, and raise a "BUG" in balloon_page_dequeue when page list
will be empty.

So, the simplest solution would be to check that the number of releases
pages is less or equal to the number taken pages.

Cc: stable@vger.kernel.org
Signed-off-by: Konstantin Neumoin <kneumoin@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-08-01 21:44:51 +03:00
Minchan Kim dd4123f324 mm: fix build warnings in <linux/compaction.h>
Randy reported below build error.

> In file included from ../include/linux/balloon_compaction.h:48:0,
>                  from ../mm/balloon_compaction.c:11:
> ../include/linux/compaction.h:237:51: warning: 'struct node' declared inside parameter list [enabled by default]
>  static inline int compaction_register_node(struct node *node)
> ../include/linux/compaction.h:237:51: warning: its scope is only this definition or declaration, which is probably not what you want [enabled by default]
> ../include/linux/compaction.h:242:54: warning: 'struct node' declared inside parameter list [enabled by default]
>  static inline void compaction_unregister_node(struct node *node)
>

It was caused by non-lru page migration which needs compaction.h but
compaction.h doesn't include any header to be standalone.

I think proper header for non-lru page migration is migrate.h rather
than compaction.h because migrate.h has already headers needed to work
non-lru page migration indirectly like isolate_mode_t, migrate_mode
MIGRATEPAGE_SUCCESS.

[akpm@linux-foundation.org: revert mm-balloon-use-general-non-lru-movable-page-feature-fix.patch temp fix]
Link: http://lkml.kernel.org/r/20160610003304.GE29779@bbox
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Gioh Kim <gi-oh.kim@profitbricks.com>
Cc: Rafael Aquini <aquini@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26 16:19:19 -07:00
Minchan Kim b1123ea6d3 mm: balloon: use general non-lru movable page feature
Now, VM has a feature to migrate non-lru movable pages so balloon
doesn't need custom migration hooks in migrate.c and compaction.c.

Instead, this patch implements the page->mapping->a_ops->
{isolate|migrate|putback} functions.

With that, we could remove hooks for ballooning in general migration
functions and make balloon compaction simple.

[akpm@linux-foundation.org: compaction.h requires that the includer first include node.h]
Link: http://lkml.kernel.org/r/1464736881-24886-4-git-send-email-minchan@kernel.org
Signed-off-by: Gioh Kim <gi-oh.kim@profitbricks.com>
Signed-off-by: Minchan Kim <minchan@kernel.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Rafael Aquini <aquini@redhat.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26 16:19:19 -07:00
Michael S. Tsirkin 87c9403b0d virtio_balloon: fix PFN format for virtio-1
Everything should be LE when using virtio-1, but
the linux balloon driver does not seem to care about that.

Reported-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2016-05-22 19:44:13 +03:00
Dan Carpenter e00f7bd221 virtio: Silence uninitialized variable warning
Smatch complains that we might not initialize "queue".  The issue is
callers like setup_vq() from virtio_pci_modern.c where "num" could be
something like 2 and "vring_align" is 64.  In that case, vring_size() is
less than PAGE_SIZE.  It won't happen in real life, but we're getting
the value of "num" from a register so it's not really possible to tell
what value it holds with static analysis.

Let's just silence the warning.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-05-01 15:50:08 +03:00
Michael S. Tsirkin 05dbcb4307 virtio: virtio 1.0 cs04 spec compliance for reset
The spec says: after writing 0 to device_status, the driver MUST wait
for a read of device_status to return 0 before reinitializing the
device.

Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2016-04-07 15:16:39 +03:00