Signed-off-by: Libo Chen <libo.chen@huawei.com>
Cc: Samuel Ortiz <samuel@sortiz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Previous guard of IS_ENABLED(CONFIG_IPV6) is not sufficient when cxgbi drivers
are built into kernel but ipv6 is not.
v2: Use Kconfig to disable compiling cxgbi built into kernel when ipv6 is
compiled as a module
Fixes: e81fbf6cd6 ("libcxgbi:cxgb4i Guard ipv6 code with a config check")
Fixes: fc8d0590d9 ("libcxgbi: Add ipv6 api to driver")
Signed-off-by: Anish Bhatt <anish@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When tp->hw_stats is 0, tg3_get_stats64 should display previously
recorded stats. So it returns &tp->net_stats_prev. But the caller,
dev_get_stats, ignores the return value.
Fix this by assigning tp->net_stats_prev to stats and returning stats.
Signed-off-by: Govindarajulu Varadarajan <_govind@gmx.com>
Acked-by: Prashant Sreedharan <prashant@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
At the tail of vnet_event(), if we hit the maybe_tx_wakeup()
condition, we try to take the netif_tx_lock() in the
recv-interrupt-context and can deadlock with dev_watchdog().
vnet_event() should schedule maybe_tx_wakeup() as a tasklet
to avoid this deadlock
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ldc_rx -> vnet_rx -> .. -> vnet_walk_rx->vnet_send_ack should not
spin into an infinite loop waiting EAGAIN to lift.
The sender could have sent us a burst, and gone to lunch without
doing any more ldc_read()'s. That should not cause the receiver to
loop infinitely till soft-lockup kicks in.
Similarly __vnet_tx_trigger should only loop on EAGAIN a finite
number of times. The caller (vnet_start_xmit()) already has code
to reset the dring state and bail on errors from __vnet_tx_trigger
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: Raghuram Kothakota <raghuram.kothakota@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
No need to ask for an ack with every vnet_start_xmit()- the single
ACK with DRING_STOPPED is sufficient for the protocol, and we free
the sk_buff in vnet_start_xmit itself, so we dont need an ACK back.
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: Raghuram Kothakota <raghuram.kothakota@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
b67bfe0d42 (hlist: drop the node
parameter from iterators) dropped the node parameter from
iterators which lec_tbl_walk() was using to iterate the list.
Signed-off-by: Chas Williams <chas@cmf.nrl.navy.mil>
Signed-off-by: David S. Miller <davem@davemloft.net>
One should not call blocking primitives inside a wait loop, since both
require task_struct::state to sleep, so the inner will destroy the
outer state.
sigd_enq() will possibly sleep for alloc_skb(). Move sigd_enq() before
prepare_to_wait() to avoid sleeping while waiting interruptibly. You do
not actually need to call sigd_enq() after the initial prepare_to_wait()
because we test the termination condition before calling schedule().
Based on suggestions from Peter Zijlstra.
Signed-off-by: Chas Williams <chas@cmf.n4rl.navy.mil>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
On IOMMU systems DMA mapping can fail, we need to check for
that possibility.
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ovs_vport_alloc() bails out without freeing the memory 'vport' points to.
Picked up by Coverity - CID 1230503.
Fixes: 5cd667b0a4 ("openvswitch: Allow each vport to have an array of 'port_id's.")
Signed-off-by: Christoph Jaeger <cj@linux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
"Several networking final fixes and tidies for the merge window:
1) Changes during the merge window unintentionally took away the
ability to build bluetooth modular, fix from Geert Uytterhoeven.
2) Several phy_node reference count bug fixes from Uwe Kleine-König.
3) Fix ucc_geth build failures, also from Uwe Kleine-König.
4) Fix klog false positivies when netlink messages go to network
taps, by properly resetting the network header. Fix from Daniel
Borkmann.
5) Sizing estimate of VF netlink messages is too small, from Jiri
Benc.
6) New APM X-Gene SoC ethernet driver, from Iyappan Subramanian.
7) VLAN untagging is erroneously dependent upon whether the VLAN
module is loaded or not, but there are generic dependencies that
matter wrt what can be expected as the SKB enters the stack.
Make the basic untagging generic code, and do it unconditionally.
From Vlad Yasevich.
8) xen-netfront only has so many slots in it's transmit queue so
linearize packets that have too many frags. From Zoltan Kiss.
9) Fix suspend/resume PHY handling in bcmgenet driver, from Florian
Fainelli"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (55 commits)
net: bcmgenet: correctly resume adapter from Wake-on-LAN
net: bcmgenet: update UMAC_CMD only when link is detected
net: bcmgenet: correctly suspend and resume PHY device
net: bcmgenet: request and enable main clock earlier
net: ethernet: myricom: myri10ge: myri10ge.c: Cleaning up missing null-terminate after strncpy call
xen-netfront: Fix handling packets on compound pages with skb_linearize
net: fec: Support phys probed from devicetree and fixed-link
smsc: replace WARN_ON() with WARN_ON_SMP()
xen-netback: Don't deschedule NAPI when carrier off
net: ethernet: qlogic: qlcnic: Remove duplicate object file from Makefile
wan: wanxl: Remove typedefs from struct names
m68k/atari: EtherNEC - ethernet support (ne)
net: ethernet: ti: cpmac.c: Cleaning up missing null-terminate after strncpy call
hdlc: Remove typedefs from struct names
airo_cs: Remove typedef local_info_t
atmel: Remove typedef atmel_priv_ioctl
com20020_cs: Remove typedef com20020_dev_t
ethernet: amd: Remove typedef local_info_t
net: Always untag vlan-tagged traffic on input.
drivers: net: Add APM X-Gene SoC ethernet driver support.
...
Pull Sparc fixes from David Miller:
"Sparc bug fixes, one of which was preventing successful SMP boots with
mainline"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
sparc64: Fix pcr_ops initialization and usage bugs.
sparc64: Do not disable interrupts in nmi_cpu_busy()
sparc: Hook up seccomp and getrandom system calls.
sparc: fix decimal printf format specifiers prefixed with 0x
Pull x86/apic updates from Thomas Gleixner:
"This is a major overhaul to the x86 apic subsystem consisting of the
following parts:
- Remove obsolete APIC driver abstractions (David Rientjes)
- Use the irqdomain facilities to dynamically allocate IRQs for
IOAPICs. This is a prerequisite to enable IOAPIC hotplug support,
and it also frees up wasted vectors (Jiang Liu)
- Misc fixlets.
Despite the hickup in Ingos previous pull request - caused by the
missing fixup for the suspend/resume issue reported by Borislav - I
strongly recommend that this update finds its way into 3.17. Some
history for you:
This is preparatory work for physical IOAPIC hotplug. The first
attempt to support this was done by Yinghai and I shot it down because
it just added another layer of obscurity and complexity to the already
existing mess without tackling the underlying shortcomings of the
current implementation.
After quite some on- and offlist discussions, I requested that the
design of this functionality must use generic infrastructure, i.e.
irq domains, which provide all the mechanisms to dynamically map linux
interrupt numbers to physical interrupts.
Jiang picked up the idea and did a great job of consolidating the
existing interfaces to manage the x86 (IOAPIC) interrupt system by
utilizing irq domains.
The testing in tip, Linux-next and inside of Intel on various machines
did not unearth any oddities until Borislav exposed it to one of his
oddball machines. The issue was resolved quickly, but unfortunately
the fix fell through the cracks and did not hit the tip tree before
Ingo sent the pull request. Not entirely Ingos fault, I also assumed
that the fix was already merged when Ingo asked me whether he could
send it.
Nevertheless this work has a proper design, has undergone several
rounds of review and the final fallout after applying it to tip and
integrating it into Linux-next has been more than moderate. It's the
ground work not only for IOAPIC hotplug, it will also allow us to move
the lowlevel vector allocation into the irqdomain hierarchy, which
will benefit other architectures as well. Patches are posted already,
but they are on hold for two weeks, see below.
I really appreciate the competence and responsiveness Jiang has shown
in course of this endavour. So I'm sure that any fallout of this will
be addressed in a timely manner.
FYI, I'm vanishing for 2 weeks into my annual kids summer camp kitchen
duty^Wvacation, while you folks are drooling at KS/LinuxCon :) But HPA
will have a look at the hopefully zero fallout until I'm back"
* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits)
x86, irq, PCI: Keep IRQ assignment for PCI devices during suspend/hibernation
x86/apic/vsmp: Make is_vsmp_box() static
x86, apic: Remove enable_apic_mode callback
x86, apic: Remove setup_portio_remap callback
x86, apic: Remove multi_timer_check callback
x86, apic: Replace noop_check_apicid_used
x86, apic: Remove check_apicid_present callback
x86, apic: Remove mps_oem_check callback
x86, apic: Remove smp_callin_clear_local_apic callback
x86, apic: Replace trampoline physical addresses with defaults
x86, apic: Remove x86_32_numa_cpu_node callback
x86: intel-mid: Use the new io_apic interfaces
x86, vsmp: Remove is_vsmp_box() from apic_is_clustered_box()
x86, irq: Clean up irqdomain transition code
x86, irq, devicetree: Release IOAPIC pin when PCI device is disabled
x86, irq, SFI: Release IOAPIC pin when PCI device is disabled
x86, irq, mpparse: Release IOAPIC pin when PCI device is disabled
x86, irq, ACPI: Release IOAPIC pin when PCI device is disabled
x86, irq: Introduce helper functions to release IOAPIC pin
x86, irq: Simplify the way to handle ISA IRQ
...
Pull x86/efix fixes from Peter Anvin:
"Two EFI-related Kconfig changes, which happen to touch immediately
adjacent lines in Kconfig and thus collapse to a single patch"
* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/efi: Enforce CONFIG_RELOCATABLE for EFI boot stub
x86/efi: Fix 3DNow optimization build failure in EFI stub
Pull x86/xsave changes from Peter Anvin:
"This is a patchset to support the XSAVES instruction required to
support context switch of supervisor-only features in upcoming
silicon.
This patchset missed the 3.16 merge window, which is why it is based
on 3.15-rc7"
* 'x86-xsave-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, xsave: Add forgotten inline annotation
x86/xsaves: Clean up code in xstate offsets computation in xsave area
x86/xsave: Make it clear that the XSAVE macros use (%edi)/(%rdi)
Define kernel API to get address of each state in xsave area
x86/xsaves: Enable xsaves/xrstors
x86/xsaves: Call booting time xsaves and xrstors in setup_init_fpu_buf
x86/xsaves: Save xstate to task's xsave area in __save_fpu during booting time
x86/xsaves: Add xsaves and xrstors support for booting time
x86/xsaves: Clear reserved bits in xsave header
x86/xsaves: Use xsave/xrstor for saving and restoring user space context
x86/xsaves: Use xsaves/xrstors for context switch
x86/xsaves: Use xsaves/xrstors to save and restore xsave area
x86/xsaves: Define a macro for handling xsave/xrstor instruction fault
x86/xsaves: Define macros for xsave instructions
x86/xsaves: Change compacted format xsave area header
x86/alternative: Add alternative_input_2 to support alternative with two features and input
x86/xsaves: Add a kernel parameter noxsaves to disable xsaves/xrstors
Just a couple of minor static analysis fixes, removal of a NULL check
that should never happen, and fix an error check where an unsigned value
was being checked to see if it was negative.
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Merge tag 'metag-for-v3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag
Pull metag architecture updates from James Hogan:
"Just a couple of minor static analysis fixes, removal of a NULL check
that should never happen, and fix an error check where an unsigned
value was being checked to see if it was negative"
* tag 'metag-for-v3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag:
metag: cachepart: Fix failure check
metag: hugetlbpage: Remove null pointer checks that could never happen
Highlights include:
- Stable fix for a bug in nfs3_list_one_acl()
- Speed up NFS path walks by supporting LOOKUP_RCU
- More read/write code cleanups
- pNFS fixes for layout return on close
- Fixes for the RCU handling in the rpcsec_gss code
- More NFS/RDMA fixes
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Merge tag 'nfs-for-3.17-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
- stable fix for a bug in nfs3_list_one_acl()
- speed up NFS path walks by supporting LOOKUP_RCU
- more read/write code cleanups
- pNFS fixes for layout return on close
- fixes for the RCU handling in the rpcsec_gss code
- more NFS/RDMA fixes"
* tag 'nfs-for-3.17-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (79 commits)
nfs: reject changes to resvport and sharecache during remount
NFS: Avoid infinite loop when RELEASE_LOCKOWNER getting expired error
SUNRPC: remove all refcounting of groupinfo from rpcauth_lookupcred
NFS: fix two problems in lookup_revalidate in RCU-walk
NFS: allow lockless access to access_cache
NFS: teach nfs_lookup_verify_inode to handle LOOKUP_RCU
NFS: teach nfs_neg_need_reval to understand LOOKUP_RCU
NFS: support RCU_WALK in nfs_permission()
sunrpc/auth: allow lockless (rcu) lookup of credential cache.
NFS: prepare for RCU-walk support but pushing tests later in code.
NFS: nfs4_lookup_revalidate: only evaluate parent if it will be used.
NFS: add checks for returned value of try_module_get()
nfs: clear_request_commit while holding i_lock
pnfs: add pnfs_put_lseg_async
pnfs: find swapped pages on pnfs commit lists too
nfs: fix comment and add warn_on for PG_INODE_REF
nfs: check wait_on_bit_lock err in page_group_lock
sunrpc: remove "ec" argument from encrypt_v2 operation
sunrpc: clean up sparse endianness warnings in gss_krb5_wrap.c
sunrpc: clean up sparse endianness warnings in gss_krb5_seal.c
...
This update contains:
o conversion of the XFS core to pass negative error numbers
o restructing of core XFS code that is shared with userspace to fs/xfs/libxfs
o introduction of sysfs interface for XFS
o bulkstat refactoring
o demand driven speculative preallocation removal
o XFS now always requires 64 bit sectors to be configured
o metadata verifier changes to ensure CRCs are calculated during log recovery
o various minor code cleanups
o miscellaneous bug fixes
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Merge tag 'xfs-for-linus-3.17-rc1' of git://oss.sgi.com/xfs/xfs
Pull xfs update from Dave Chinner:
"This update contains:
- conversion of the XFS core to pass negative error numbers
- restructing of core XFS code that is shared with userspace to
fs/xfs/libxfs
- introduction of sysfs interface for XFS
- bulkstat refactoring
- demand driven speculative preallocation removal
- XFS now always requires 64 bit sectors to be configured
- metadata verifier changes to ensure CRCs are calculated during log
recovery
- various minor code cleanups
- miscellaneous bug fixes
The diffstat is kind of noisy because of the restructuring of the code
to make kernel/userspace code sharing simpler, along with the XFS wide
change to use the standard negative error return convention (at last!)"
* tag 'xfs-for-linus-3.17-rc1' of git://oss.sgi.com/xfs/xfs: (45 commits)
xfs: fix coccinelle warnings
xfs: flush both inodes in xfs_swap_extents
xfs: fix swapext ilock deadlock
xfs: kill xfs_vnode.h
xfs: kill VN_MAPPED
xfs: kill VN_CACHED
xfs: kill VN_DIRTY()
xfs: dquot recovery needs verifiers
xfs: quotacheck leaves dquot buffers without verifiers
xfs: ensure verifiers are attached to recovered buffers
xfs: catch buffers written without verifiers attached
xfs: avoid false quotacheck after unclean shutdown
xfs: fix rounding error of fiemap length parameter
xfs: introduce xfs_bulkstat_ag_ichunk
xfs: require 64-bit sector_t
xfs: fix uflags detection at xfs_fs_rm_xquota
xfs: remove XFS_IS_OQUOTA_ON macros
xfs: tidy up xfs_set_inode32
xfs: allow inode allocations in post-growfs disk space
xfs: mark xfs_qm_quotacheck as static
...
Pull quota, reiserfs, UDF updates from Jan Kara:
"Scalability improvements for quota, a few reiserfs fixes, and couple
of misc cleanups (udf, ext2)"
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
reiserfs: Fix use after free in journal teardown
reiserfs: fix corruption introduced by balance_leaf refactor
udf: avoid redundant memcpy when writing data in ICB
fs/udf: re-use hex_asc_upper_{hi,lo} macros
fs/quota: kernel-doc warning fixes
udf: use linux/uaccess.h
fs/ext2/super.c: Drop memory allocation cast
quota: remove dqptr_sem
quota: simplify remove_inode_dquot_ref()
quota: avoid unnecessary dqget()/dqput() calls
quota: protect Q_GETFMT by dqonoff_mutex
Pull Ceph updates from Sage Weil:
"There is a lot of refactoring and hardening of the libceph and rbd
code here from Ilya that fix various smaller bugs, and a few more
important fixes with clone overlap. The main fix is a critical change
to the request_fn handling to not sleep that was exposed by the recent
mutex changes (which will also go to the 3.16 stable series).
Yan Zheng has several fixes in here for CephFS fixing ACL handling,
time stamps, and request resends when the MDS restarts.
Finally, there are a few cleanups from Himangi Saraogi based on
Coccinelle"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (39 commits)
libceph: set last_piece in ceph_msg_data_pages_cursor_init() correctly
rbd: remove extra newlines from rbd_warn() messages
rbd: allocate img_request with GFP_NOIO instead GFP_ATOMIC
rbd: rework rbd_request_fn()
ceph: fix kick_requests()
ceph: fix append mode write
ceph: fix sizeof(struct tYpO *) typo
ceph: remove redundant memset(0)
rbd: take snap_id into account when reading in parent info
rbd: do not read in parent info before snap context
rbd: update mapping size only on refresh
rbd: harden rbd_dev_refresh() and callers a bit
rbd: split rbd_dev_spec_update() into two functions
rbd: remove unnecessary asserts in rbd_dev_image_probe()
rbd: introduce rbd_dev_header_info()
rbd: show the entire chain of parent images
ceph: replace comma with a semicolon
rbd: use rbd_segment_name_free() instead of kfree()
ceph: check zero length in ceph_sync_read()
ceph: reset r_resend_mds after receiving -ESTALE
...
fixes are:
* UBI deleted list items while iterating the list with 'list_for_each_entry'
* The UBI block driver did not work properly with very large UBI volumes
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Merge tag 'upstream-3.17-rc1' of git://git.infradead.org/linux-ubifs
Pull UBI/UBIFS changes from Artem Bityutskiy:
"No significant changes, mostly small fixes here and there. The more
important fixes are:
- UBI deleted list items while iterating the list with
'list_for_each_entry'
- The UBI block driver did not work properly with very large UBI
volumes"
* tag 'upstream-3.17-rc1' of git://git.infradead.org/linux-ubifs: (21 commits)
UBIFS: Add log overlap assertions
Revert "UBIFS: add a log overlap assertion"
UBI: bugfix in ubi_wl_flush()
UBI: block: Avoid disk size integer overflow
UBI: block: Set disk_capacity out of the mutex
UBI: block: Make ubiblock_resize return something
UBIFS: add a log overlap assertion
UBIFS: remove unnecessary check
UBIFS: remove mst_mutex
UBIFS: kernel-doc warning fix
UBI: init_volumes: Ignore volumes with no LEBs
UBIFS: replace seq_printf by seq_puts
UBIFS: replace count*size kzalloc by kcalloc
UBIFS: kernel-doc warning fix
UBIFS: fix error path in create_default_filesystem()
UBIFS: fix spelling of "scanned"
UBIFS: fix some comments
UBIFS: remove useless @ecc in struct ubifs_scan_leb
UBIFS: remove useless statements
UBIFS: Add missing break statements in dbg_chk_pnode()
...
Somehow we ended up with a duplicate line in edt_ft5x06_register_write()
Signed-off-by: Maks Naumov <maksqwe1@ukr.net>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Xbox One controllers require an initialization message to start sending
data, so xpad_init_output becomes a required function. The Xbox One
controller does not have LEDs like the Xbox 360 controller, so that
functionality is not implemented. The format of messages controlling rumble
is currently undocumented, so rumble support is not yet implemented.
Note that Xbox One controller advertises three interfaces with the same
interface class, subclass and protocol, so we have to also match against
interface number.
Signed-off-by: Ted Mielczarek <ted@mielczarek.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
This should fix the following issues reported by Coverity:
*** CID 1230625: Logically dead code (DEADCODE)
/drivers/input/touchscreen/atmel_mxt_ts.c: 1692 in mxt_initialize()
*** CID 1230627: Missing break in switch (MISSING_BREAK)
/drivers/input/touchscreen/atmel_mxt_ts.c: 1436 in mxt_get_object_table()
*** CID 1230629: Out-of-bounds write (OVERRUN)
/drivers/input/touchscreen/atmel_mxt_ts.c: 1267 in mxt_update_cfg()
*** CID 1230632: Unused pointer value (UNUSED_VALUE)
/drivers/input/touchscreen/atmel_mxt_ts.c: 1211 in mxt_update_cfg()
Acked-by: Nick Dyer <nick.dyer@itdev.co.uk>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Let's split config update code a bit so it is hopefully a bit easier to
read. Also, the firmware update callback should be the entity releasing
firmware blob, not lower layers.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>
I think having control flow with 2 goto/labels/flags is quite hard to read,
this version is a bit more readable IMO.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>
Add tracepoint to track hugepage invalidate. This help us
in debugging difficult to track bugs.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
On ppc64 we support 4K hash pte with 64K page size. That requires
us to track the hash pte slot information on a per 4k basis. We do that
by storing the slot details in the second half of pte page. The pte bit
_PAGE_COMBO is used to indicate whether the second half need to be
looked while building real_pte. We need to use read memory barrier while
doing that so that load of hidx is not reordered w.r.t _PAGE_COMBO
check. On the store side we already do a lwsync in __hash_page_4K
CC: <stable@vger.kernel.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We would get wrong results in compiler recomputed old_pmd. Avoid
that by using ACCESS_ONCE
CC: <stable@vger.kernel.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
As per ISA, for 4k base page size we compare 14..65 bits of VA specified
with the entry_VA in tlb. That implies we need to make sure we do a
tlbie with all the possible 4k va we used to access the 16MB hugepage.
With 64k base page size we compare 14..57 bits of VA. Hence we cannot
ignore the lower 24 bits of va while tlbie .We also cannot tlb
invalidate a 16MB entry with just one tlbie instruction because
we don't track which va was used to instantiate the tlb entry.
CC: <stable@vger.kernel.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
If we changed base page size of the segment, either via sub_page_protect
or via remap_4k_pfn, we do a demote_segment which doesn't flush the hash
table entries. We do a lazy hash page table flush for all mapped pages
in the demoted segment. This happens when we handle hash page fault for
these pages.
We use _PAGE_COMBO bit along with _PAGE_HASHPTE to indicate whether a
pte is backed by 4K hash pte. If we find _PAGE_COMBO not set on the pte,
that implies that we could possibly have older 64K hash pte entries in
the hash page table and we need to invalidate those entries.
Use _PAGE_COMBO to determine the page size with which we should
invalidate the hash table entries on unmap.
CC: <stable@vger.kernel.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
If we changed base page size of the segment, either via sub_page_protect
or via remap_4k_pfn, we do a demote_segment which doesn't flush the hash
table entries. We do a lazy hash page table flush for all mapped pages
in the demoted segment. This happens when we handle hash page fault
for these pages.
We use _PAGE_COMBO bit along with _PAGE_HASHPTE to indicate whether a
pte is backed by 4K hash pte. If we find _PAGE_COMBO not set on the pte,
that implies that we could possibly have older 64K hash pte entries in
the hash page table and we need to invalidate those entries.
Handle this correctly for 16M pages
CC: <stable@vger.kernel.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The segment identifier and segment size will remain the same in
the loop, So we can compute it outside. We also change the
hugepage_invalidate interface so that we can use it the later patch
CC: <stable@vger.kernel.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
With hugepages, we store the hpte valid information in the pte page
whose address is stored in the second half of the PMD. Use a
write barrier to make sure clearing pmd busy bit and updating
hpte valid info are ordered properly.
CC: <stable@vger.kernel.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
There is an issue currently where NUMA information is used on powerpc
(and possibly ia64) before it has been read from the device-tree, which
leads to large slab consumption with CONFIG_SLUB and memoryless nodes.
NUMA powerpc non-boot CPU's cpu_to_node/cpu_to_mem is only accurate
after start_secondary(), similar to ia64, which is invoked via
smp_init().
Commit 6ee0578b4d ("workqueue: mark init_workqueues() as
early_initcall()") made init_workqueues() be invoked via
do_pre_smp_initcalls(), which is obviously before the secondary
processors are online.
Additionally, the following commits changed init_workqueues() to use
cpu_to_node to determine the node to use for kthread_create_on_node:
bce903809a ("workqueue: add wq_numa_tbl_len and
wq_numa_possible_cpumask[]")
f3f90ad469 ("workqueue: determine NUMA node of workers accourding to
the allowed cpumask")
Therefore, when init_workqueues() runs, it sees all CPUs as being on
Node 0. On LPARs or KVM guests where Node 0 is memoryless, this leads to
a high number of slab deactivations
(http://www.spinics.net/lists/linux-mm/msg67489.html).
Fix this by initializing the powerpc-specific CPU<->node/local memory
node mapping as early as possible, which on powerpc is
do_init_bootmem(). Currently that function initializes the mapping for
the boot CPU, but we extend it to setup the mapping for all possible
CPUs. Then, in smp_prepare_cpus(), we can correspondingly set the
per-cpu values for all possible CPUs. That ensures that before the
early_initcalls run (and really as early as possible), the per-cpu NUMA
mapping is accurate.
While testing memoryless nodes on PowerKVM guests with a fix to the
workqueue logic to use cpu_to_mem() instead of cpu_to_node(), with a
guest topology of:
available: 2 nodes (0-1)
node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
node 0 size: 0 MB
node 0 free: 0 MB
node 1 cpus: 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99
node 1 size: 16336 MB
node 1 free: 15329 MB
node distances:
node 0 1
0: 10 40
1: 40 10
the slab consumption decreases from
Slab: 932416 kB
SUnreclaim: 902336 kB
to
Slab: 395264 kB
SUnreclaim: 359424 kB
And we a corresponding increase in the slab efficiency from
slab mem objs slabs
used active active
------------------------------------------------------------
kmalloc-16384 337 MB 11.28% 100.00%
task_struct 288 MB 9.93% 100.00%
to
slab mem objs slabs
used active active
------------------------------------------------------------
kmalloc-16384 37 MB 100.00% 100.00%
task_struct 31 MB 100.00% 100.00%
Powerpc didn't support memoryless nodes until recently (64bb80d87f
"powerpc/numa: Enable CONFIG_HAVE_MEMORYLESS_NODES" and 8c27226119
"powerpc/numa: Enable USE_PERCPU_NUMA_NODE_ID"). Those commits also
helped improve memory consumption with these kind of environments.
Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Free memory allocated using kmem_cache_zalloc using kmem_cache_free
rather than kfree.
The Coccinelle semantic patch that makes this change is as follows:
// <smpl>
@@
expression x,E,c;
@@
x = \(kmem_cache_alloc\|kmem_cache_zalloc\|kmem_cache_alloc_node\)(c,...)
... when != x = E
when != &x
?-kfree(x)
+kmem_cache_free(c,x)
// </smpl>
Signed-off-by: Himangi Saraogi <himangi774@gmail.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
A buffer returned by H_VTERM_PARTNER_INFO contains device information
in big endian format, causing problems for little endian architectures.
This patch ensures that they are in cpu endian.
Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
xmon only soft disables interrupts. This seems like a bad idea - we
certainly don't want decrementer and PMU exceptions going off when
we are debugging something inside xmon.
This issue was uncovered when the hard lockup detector went off
inside xmon. To ensure we wont get a spurious hard lockup warning,
I also call touch_nmi_watchdog() when exiting xmon.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
It appears that commits 7f06f21d40 ("powerpc/tm: Add checking to
treclaim/trechkpt") and e4e3812150 ("KVM: PPC: Book3S HV: Add
transactional memory support") both added definitions of TEXASR_FS.
Remove one of them. At the same time, fix the alignment of the remaining
definition (should be tab-separated like the rest of the #defines).
Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Avoids this warning:
arch/powerpc/boot/gunzip_util.c:118:9: warning: comparison of distinct pointer types lacks a cast
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
PowerNV platform is capable of capturing host memory region when system
crashes (because of host/firmware). We have new OPAL API to register/
unregister memory region to be captured when system crashes.
This patch adds support for new API. Also during boot time we register
kernel log buffer and unregister before doing kexec.
Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Platforms like IBM Power Systems supports service processor
assisted dump. It provides interface to add memory region to
be captured when system is crashed.
During initialization/running we can add kernel memory region
to be collected.
Presently we don't have a way to get the log buffer base address
and size. This patch adds support to return log buffer address
and size.
Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
We have been a bit slack about updating the CPU_FTRS_POSSIBLE and
CPU_FTRS_ALWAYS masks. When we added POWER8, and also POWER8E we forgot
to update the ALWAYS mask. And when we added POWER8_DD1 we forgot to
update both the POSSIBLE and ALWAYS masks.
Luckily this hasn't caused any actual bugs AFAICS. Failing to update the
ALWAYS mask just forgoes a potential optimisation opportunity. Failing
to update the POSSIBLE mask for POWER8_DD1 is also OK because it only
removes a bit rather than adding any.
Regardless they should all be in both masks so as to avoid any future
bugs when the set of ALWAYS/POSSIBLE bits changes, or the masks
themselves change.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Michael Neuling <mikey@neuling.org>
Acked-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch disables the branch target address CAM which under specific
circumstances may cause the processor to skip execution of 1-4
instructions. This fixes IBM Erratum #47.
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When we take full hotplug to recover from EEH errors, PCI buses
could be involved. For the case, the child devices of involved
PCI buses can't be attached to IOMMU group properly, which is
caused by commit 3f28c5a ("powerpc/powernv: Reduce multi-hit of
iommu_add_device()").
When adding the PCI devices of the newly created PCI buses to
the system, the IOMMU group is expected to be added in (C).
(A) fails to bind the IOMMU group because bus->is_added is
false. (B) fails because the device doesn't have binding IOMMU
table yet. bus->is_added is set to true at end of (C) and
pdev->is_added is set to true at (D).
pcibios_add_pci_devices()
pci_scan_bridge()
pci_scan_child_bus()
pci_scan_slot()
pci_scan_single_device()
pci_scan_device()
pci_device_add()
pcibios_add_device() A: Ignore
device_add() B: Ignore
pcibios_fixup_bus()
pcibios_setup_bus_devices()
pcibios_setup_device() C: Hit
pcibios_finish_adding_to_bus()
pci_bus_add_devices()
pci_bus_add_device() D: Add device
If the parent PCI bus isn't involved in hotplug, the IOMMU
group is expected to be bound in (B). (A) should fail as the
sysfs entries aren't populated.
The patch fixes the issue by reverting commit 3f28c5a and remove
WARN_ON() in iommu_add_device() to allow calling the function
even the specified device already has associated IOMMU group.
Cc: <stable@vger.kernel.org> # 3.16+
Reported-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Acked-by: Wei Yang <weiyang@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Similar to the previous commit which described why we need to add a
barrier to arch_spin_is_locked(), we have a similar problem with
spin_unlock_wait().
We need a barrier on entry to ensure any spinlock we have previously
taken is visibly locked prior to the load of lock->slock.
It's also not clear if spin_unlock_wait() is intended to have ACQUIRE
semantics. For now be conservative and add a barrier on exit to give it
ACQUIRE semantics.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The kernel defines the function spin_is_locked(), which can be used to
check if a spinlock is currently locked.
Using spin_is_locked() on a lock you don't hold is obviously racy. That
is, even though you may observe that the lock is unlocked, it may become
locked at any time.
There is (at least) one exception to that, which is if two locks are
used as a pair, and the holder of each checks the status of the other
before doing any update.
Assuming *A and *B are two locks, and *COUNTER is a shared non-atomic
value:
The first CPU does:
spin_lock(*A)
if spin_is_locked(*B)
# nothing
else
smp_mb()
LOAD r = *COUNTER
r++
STORE *COUNTER = r
spin_unlock(*A)
And the second CPU does:
spin_lock(*B)
if spin_is_locked(*A)
# nothing
else
smp_mb()
LOAD r = *COUNTER
r++
STORE *COUNTER = r
spin_unlock(*B)
Although this is a strange locking construct, it should work.
It seems to be understood, but not documented, that spin_is_locked() is
not a memory barrier, so in the examples above and below the caller
inserts its own memory barrier before acting on the result of
spin_is_locked().
For now we assume spin_is_locked() is implemented as below, and we break
it out in our examples:
bool spin_is_locked(*LOCK) {
LOAD l = *LOCK
return l.locked
}
Our intuition is that there should be no problem even if the two code
sequences run simultaneously such as:
CPU 0 CPU 1
==================================================
spin_lock(*A) spin_lock(*B)
LOAD b = *B LOAD a = *A
if b.locked # true if a.locked # true
# nothing # nothing
spin_unlock(*A) spin_unlock(*B)
If one CPU gets the lock before the other then it will do the update and
the other CPU will back off:
CPU 0 CPU 1
==================================================
spin_lock(*A)
LOAD b = *B
spin_lock(*B)
if b.locked # false LOAD a = *A
else if a.locked # true
smp_mb() # nothing
LOAD r1 = *COUNTER spin_unlock(*B)
r1++
STORE *COUNTER = r1
spin_unlock(*A)
However in reality spin_lock() itself is not indivisible. On powerpc we
implement it as a load-and-reserve and store-conditional.
Ignoring the retry logic for the lost reservation case, it boils down to:
spin_lock(*LOCK) {
LOAD l = *LOCK
l.locked = true
STORE *LOCK = l
ACQUIRE_BARRIER
}
The ACQUIRE_BARRIER is required to give spin_lock() ACQUIRE semantics as
defined in memory-barriers.txt:
This acts as a one-way permeable barrier. It guarantees that all
memory operations after the ACQUIRE operation will appear to happen
after the ACQUIRE operation with respect to the other components of
the system.
On modern powerpc systems we use lwsync for ACQUIRE_BARRIER. lwsync is
also know as "lightweight sync", or "sync 1".
As described in Power ISA v2.07 section B.2.1.1, in this scenario the
lwsync is not the barrier itself. It instead causes the LOAD of *LOCK to
act as the barrier, preventing any loads or stores in the locked region
from occurring prior to the load of *LOCK.
Whether this behaviour is in accordance with the definition of ACQUIRE
semantics in memory-barriers.txt is open to discussion, we may switch to
a different barrier in future.
What this means in practice is that the following can occur:
CPU 0 CPU 1
==================================================
LOAD a = *A LOAD b = *B
a.locked = true b.locked = true
LOAD b = *B LOAD a = *A
STORE *A = a STORE *B = b
if b.locked # false if a.locked # false
else else
smp_mb() smp_mb()
LOAD r1 = *COUNTER LOAD r2 = *COUNTER
r1++ r2++
STORE *COUNTER = r1
STORE *COUNTER = r2 # Lost update
spin_unlock(*A) spin_unlock(*B)
That is, the load of *B can occur prior to the store that makes *A
visibly locked. And similarly for CPU 1. The result is both CPUs hold
their lock and believe the other lock is unlocked.
The easiest fix for this is to add a full memory barrier to the start of
spin_is_locked(), so adding to our previous definition would give us:
bool spin_is_locked(*LOCK) {
smp_mb()
LOAD l = *LOCK
return l.locked
}
The new barrier orders the store to the lock we are locking vs the load
of the other lock:
CPU 0 CPU 1
==================================================
LOAD a = *A LOAD b = *B
a.locked = true b.locked = true
STORE *A = a STORE *B = b
smp_mb() smp_mb()
LOAD b = *B LOAD a = *A
if b.locked # true if a.locked # true
# nothing # nothing
spin_unlock(*A) spin_unlock(*B)
Although the above example is theoretical, there is code similar to this
example in sem_lock() in ipc/sem.c. This commit in addition to the next
commit appears to be a fix for crashes we are seeing in that code where
we believe this race happens in practice.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Libo Chen