On many Marvell SoCs, the pins used for the SDIO interface are part of
the MPP pins, that are muxable pins. In order to get the muxing of
those pins correct, this commit integrates the mvsdio driver with the
pinctrl infrastructure by calling devm_pinctrl_get_select_default()
during ->probe().
Note that we permit this function to fail because not all Marvell
platforms have yet been fully converted to using the pinctrl
infrastructure.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Tested-by: Stefan Peter <s.peter@mpl.ch>
Tested-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Chris Ball <cjb@laptop.org>
Commit ee873fda3b ("gianfar: Pack struct
gfar_priv_grp into three cachelines") moved the irq number and names
off into a separate struct and created accessors for them. However
it was never tested with NET_POLL enabled, and so some conversions
that were simply overlooked went undetected until now.
Make the netpoll ones also use the gfar_irq() accessors.
Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Claudiu Manoil <claudiu.manoil@freescale.com>
Cc: Jianhua Xie <jianhua.xie@freescale.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The CONFIG_EXPERIMENTAL config item has not carried much meaning for a
while now and is almost always enabled by default. As agreed during the
Linux kernel summit, remove it from any "depends on" lines in Kconfigs.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Without this patch any kernel code that reads kernel memory in
non present kernel pte/pmds (as set by pageattr.c) will crash.
With this kernel code:
static struct page *crash_page;
static unsigned long *crash_address;
[..]
crash_page = alloc_pages(GFP_KERNEL, 9);
crash_address = page_address(crash_page);
if (set_memory_np((unsigned long)crash_address, 1))
printk("set_memory_np failure\n");
[..]
The kernel will crash if inside the "crash tool" one would try
to read the memory at the not present address.
crash> p crash_address
crash_address = $8 = (long unsigned int *) 0xffff88023c000000
crash> rd 0xffff88023c000000
[ *lockup* ]
The lockup happens because _PAGE_GLOBAL and _PAGE_PROTNONE
shares the same bit, and pageattr leaves _PAGE_GLOBAL set on a
kernel pte which is then mistaken as _PAGE_PROTNONE (so
pte_present returns true by mistake and the kernel fault then
gets confused and loops).
With THP the same can happen after we taught pmd_present to
check _PAGE_PROTNONE and _PAGE_PSE in commit
027ef6c878 ("mm: thp: fix pmd_present for
split_huge_page and PROT_NONE with THP"). THP has the same
problem with _PAGE_GLOBAL as the 4k pages, but it also has a
problem with _PAGE_PSE, which must be cleared too.
After the patch is applied copy_user correctly returns -EFAULT
and doesn't lockup anymore.
crash> p crash_address
crash_address = $9 = (long unsigned int *) 0xffff88023c000000
crash> rd 0xffff88023c000000
rd: read error: kernel virtual address: ffff88023c000000 type:
"64-bit KVADDR"
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: "H. Peter Anvin" <hpa@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
I got a report for a minor regression introduced by commit
027ef6c878 ("mm: thp: fix pmd_present for split_huge_page and
PROT_NONE with THP").
So the problem is, pageattr creates kernel pagetables (pte and
pmds) that breaks pte_present/pmd_present and the patch above
exposed this invariant breakage for pmd_present.
The same problem already existed for the pte and pte_present and
it was fixed by commit 660a293ea9 ("x86, mm: Make
spurious_fault check explicitly check the PRESENT bit") (if it
wasn't for that commit, it wouldn't even be a regression). That
fix avoids the pagefault to use pte_present. I could follow
through by stopping using pmd_present/pmd_huge too.
However I think it's more robust to fix pageattr and to clear
the PSE/GLOBAL bitflags too in addition to the present bitflag.
So the kernel page fault can keep using the regular
pte_present/pmd_present/pmd_huge.
The confusion arises because _PAGE_GLOBAL and _PAGE_PROTNONE are
sharing the same bit, and in the pmd case we pretend _PAGE_PSE
to be set only in present pmds (to facilitate split_huge_page
final tlb flush).
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: "H. Peter Anvin" <hpa@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If we aren't debugging per_cpu maps, the cpu's node is stored in
per_cpu variable numa_node. If `node' is NUMA_NO_NODE, it means
the caller wants to clear the cpu's node. So we should also
call set_cpu_numa_node() in this case.
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Running the full dynticks cputime accounting with preemptible
kernel debugging trigger the following warning:
[ 4.488303] BUG: using smp_processor_id() in preemptible [00000000] code: init/1
[ 4.490971] caller is native_sched_clock+0x22/0x80
[ 4.493663] Pid: 1, comm: init Not tainted 3.8.0+ #13
[ 4.496376] Call Trace:
[ 4.498996] [<ffffffff813410eb>] debug_smp_processor_id+0xdb/0xf0
[ 4.501716] [<ffffffff8101e642>] native_sched_clock+0x22/0x80
[ 4.504434] [<ffffffff8101db99>] sched_clock+0x9/0x10
[ 4.507185] [<ffffffff81096ccd>] fetch_task_cputime+0xad/0x120
[ 4.509916] [<ffffffff81096dd5>] task_cputime+0x35/0x60
[ 4.512622] [<ffffffff810f146e>] acct_update_integrals+0x1e/0x40
[ 4.515372] [<ffffffff8117d2cf>] do_execve_common+0x4ff/0x5c0
[ 4.518117] [<ffffffff8117cf14>] ? do_execve_common+0x144/0x5c0
[ 4.520844] [<ffffffff81867a10>] ? rest_init+0x160/0x160
[ 4.523554] [<ffffffff8117d457>] do_execve+0x37/0x40
[ 4.526276] [<ffffffff810021a3>] run_init_process+0x23/0x30
[ 4.528953] [<ffffffff81867aac>] kernel_init+0x9c/0xf0
[ 4.531608] [<ffffffff8188356c>] ret_from_fork+0x7c/0xb0
We use sched_clock() to perform and fixup the cputime
accounting. However we are calling it with preemption enabled
from the read side, which trigger the bug above.
To fix this up, use local_clock() instead. It takes care of
preemption and also provide a more reliable clock source. This
is welcome for this kind of statistic that is widely relied on
in userspace.
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Reported-by: Ingo Molnar <mingo@kernel.org>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Kevin Hilman <khilman@linaro.org>
Link: http://lkml.kernel.org/r/1361636925-22288-3-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Saw the following compiler warning on the linux-next tree:
kernel/itimer.c: In function 'set_cpu_itimer':
kernel/itimer.c:152:2: warning: passing argument 1 of 'timeval_to_cputime' discards 'const' qualifier from pointer target type [enabled by default]
...
timeval_to_cputime() is always passed a constant timeval in
argument, we need to teach the nsecs based cputime
implementation about that.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Kevin Hilman <khilman@linaro.org>
Link: http://lkml.kernel.org/r/1361636925-22288-2-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Kevin Hilman <khilman@linaro.org>
The Xtensa architecture provides a global register called THREADPTR
for the purpose of Thread Local Storage (TLS) support. This allows us
to use a fairly simple implementation, keeping the thread pointer in
the regset and simply saving and restoring it upon entering/exiting
the from user space.
Signed-off-by: Chris Zankel <chris@zankel.net>
This fixes the following build errors seen in the linux-next:
arch/xtensa/include/asm/checksum.h:247:2: error: implicit declaration of
function 'access_ok' [-Werror=implicit-function-declaration]
arch/xtensa/include/asm/checksum.h:247:16: error: 'VERIFY_WRITE' undeclared
(first use in this function)
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Now that drivers/gpio/devres.c build does not depend on GPIOLIB do not
enable GENERIC_GPIO by default to fix the following build errors seen
in the linux-next:
include/asm-generic/gpio.h:270:2: error: implicit declaration of function
'__gpio_get_value' [-Werror=implicit-function-declaration]
include/asm-generic/gpio.h:276:2: error: implicit declaration of function
'__gpio_set_value' [-Werror=implicit-function-declaration]
include/linux/gpio.h:60:19: error: redefinition of 'gpio_cansleep'
include/linux/gpio.h:62:2: error: implicit declaration of function
'__gpio_cansleep' [-Werror=implicit-function-declaration]
include/linux/gpio.h:67:2: error: implicit declaration of function
'__gpio_to_irq' [-Werror=implicit-function-declaration]
drivers/gpio/devres.c:26:2: error: implicit declaration of function
'gpio_free' [-Werror=implicit-function-declaration]
drivers/gpio/devres.c:60:2: error: implicit declaration of function
'gpio_request' [-Werror=implicit-function-declaration]
drivers/gpio/devres.c:90:2: error: implicit declaration of function
'gpio_request_one' [-Werror=implicit-function-declaration]
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Compute WindowBase and WindowMask registers correctly on ptrace calls.
Work done earlier by Maxim, Christian and Marc.
Signed-off-by: Marc Gauthier <marc@tensilica.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Support call graph profiling.
Keep upper two bits of PC unchanged through backtrace rather than take
them from sp (a1). The stack pointer is usually in the same GB (same
upper 2 bits) as PC, but technically doesn't always have to be (and
might not in the future, when taking full advantage of MMU v3).
Signed-off-by: Dan Nicolaescu <dann@xtensa-linux.org>
Signed-off-by: Pete Delaney <piet@tensilica.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Simdisk is a block device that maps to a file in the host file system.
It is usable for testing in the simulated environment, like xt-sim or
QEMU. Device binding to host file may be changed at runtime via proc
interface provided the device is not in use. Number of block devices
and initial binding to host files is controlled via kernel/module
parameters, with defaults specified in the kernel configuration.
Signed-off-by: Victor Prupis <vnp@tensilica.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
str[n]cmp functions return negative value if the first string is less
than the second, positive value if the first string is greater than the
second and zero if they are equal. This is important when these
functions are used for sorting/binary search.
With incorrect strcmp return value bsearch was always failing in the
find_symbol_in_section making it impossible to load any module.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Provide arch_get_unmapped_area function aligning shared memory mapping
addresses to the biggest of the page size or the cache way size. That
guarantees that corresponding virtual addresses of shared mappings are
cached by the same cache sets.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
This fixes the following build error in the current linux-next:
include/linux/signal.h:261:2: error: unknown type name '__sigrestore_t'
make[2]: *** [arch/xtensa/kernel/asm-offsets.s] Error 1
make[1]: *** [prepare0] Error 2
make: *** [sub-make] Error 2
that appeared after 32dae82 'consolidate kernel-side struct sigaction declarations'
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
shmctl may be called with IPC_64 flag, select function version of
ipc_parse_version to correctly handle that.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Add support for dispatching medium-priority interrupts, that is,
interrupts of priority levels 2 to EXCM_LEVEL. IRQ handling may be
preempted by higher priority IRQ.
Signed-off-by: Marc Gauthier <marc@tensilica.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
The Diamond 233L processor is a pre-configured Xtensa processor tailored
for Linux application.
Signed-off-by: Pete Delaney <piet@tensilica.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
The current rules have the .dtb files build in a different directory
from the .dts files. This patch changes xtensa to use the generic dtb
rule which builds .dtb files in the same directory as the source .dts.
This requires moving parts of arch/xtensa/boot/Makefile into newly
created arch/xtensa/boot/dts/Makefile, and updating arch/xtensa/Makefile
to call the new Makefile.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
This rename happened in 79d1c71 powerpc+of: Rename the drivers/of prom_*
functions to of_*.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
Pull signal handling cleanups from Al Viro:
"This is the first pile; another one will come a bit later and will
contain SYSCALL_DEFINE-related patches.
- a bunch of signal-related syscalls (both native and compat)
unified.
- a bunch of compat syscalls switched to COMPAT_SYSCALL_DEFINE
(fixing several potential problems with missing argument
validation, while we are at it)
- a lot of now-pointless wrappers killed
- a couple of architectures (cris and hexagon) forgot to save
altstack settings into sigframe, even though they used the
(uninitialized) values in sigreturn; fixed.
- microblaze fixes for delivery of multiple signals arriving at once
- saner set of helpers for signal delivery introduced, several
architectures switched to using those."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (143 commits)
x86: convert to ksignal
sparc: convert to ksignal
arm: switch to struct ksignal * passing
alpha: pass k_sigaction and siginfo_t using ksignal pointer
burying unused conditionals
make do_sigaltstack() static
arm64: switch to generic old sigaction() (compat-only)
arm64: switch to generic compat rt_sigaction()
arm64: switch compat to generic old sigsuspend
arm64: switch to generic compat rt_sigqueueinfo()
arm64: switch to generic compat rt_sigpending()
arm64: switch to generic compat rt_sigprocmask()
arm64: switch to generic sigaltstack
sparc: switch to generic old sigsuspend
sparc: COMPAT_SYSCALL_DEFINE does all sign-extension as well as SYSCALL_DEFINE
sparc: kill sign-extending wrappers for native syscalls
kill sparc32_open()
sparc: switch to use of generic old sigaction
sparc: switch sys_compat_rt_sigaction() to COMPAT_SYSCALL_DEFINE
mips: switch to generic sys_fork() and sys_clone()
...
Thierry writes:
"Remove a duplicate implementation of the CEA VIC lookup and move the CEA
and other mode tables to drm_edid.c to make it more difficult to create
duplicates of the tables.
Add some helpers to pack CEA-861/HDMI AVI, audio and SPD infoframes into
binary buffers that can easily be written into hardware registers. A new
helper function makes it easy construct an AVI infoframe from a DRM
display mode.
Convert the Tegra and Radeon drivers to use the new HDMI helpers."
* 'drm/hdmi-for-3.9' of git://anongit.freedesktop.org/tegra/linux:
drm/radeon: Use generic HDMI infoframe helpers
drm/tegra: Use generic HDMI infoframe helpers
drm: Add EDID helper documentation
drm: Add HDMI infoframe helpers
video: Add generic HDMI infoframe helpers
drm: Add some missing forward declarations
drm: Move mode tables to drm_edid.c
drm: Remove duplicate drm_mode_cea_vic()
Two regressions fixes from snowboarding land
* 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel:
drm/i915: Revert hdmi HDP pin checks
drm/i915: Handle untiled planes when computing their offsets
Thierry writes:
"Add support for 2 hardware overlays found on Tegra. These support YUV
pixel formats and can be used as video overlays. .mode_set_base() is
implemented and support for VBLANK and page-flipping is added.
A few minor bug fixes are also included and a new debugfs file allows
to inspect the framebuffers attached to the Tegra DRM device."
* 'drm/tegra-for-3.9' of git://anongit.freedesktop.org/tegra/linux:
drm/tegra: Add list of framebuffers to debugfs
drm/tegra: Fix color expansion
drm/tegra: Split DC_CMD_STATE_CONTROL register write
drm/tegra: Implement page-flipping support
drm/tegra: Implement VBLANK support
drm/tegra: Implement .mode_set_base()
drm/tegra: Add plane support
drm/tegra: Remove bogus tegra_framebuffer structure
drm: Add consistency check for page-flipping
There are two places to call vlan_set_encap_proto():
vlan_untag() and __pop_vlan_tci().
vlan_untag() assumes skb->data points after mac addr, otherwise
the following code
vhdr = (struct vlan_hdr *) skb->data;
vlan_tci = ntohs(vhdr->h_vlan_TCI);
__vlan_hwaccel_put_tag(skb, vlan_tci);
skb_pull_rcsum(skb, VLAN_HLEN);
won't be correct. But __pop_vlan_tci() assumes points _before_
mac addr.
In vlan_set_encap_proto(), it looks for some magic L2 value
after mac addr:
rawp = skb->data;
if (*(unsigned short *) rawp == 0xFFFF)
...
Therefore __pop_vlan_tci() is obviously wrong.
A quick fix is avoiding using skb->data in vlan_set_encap_proto(),
use 'vhdr+1' is always correct in both cases.
Cc: David S. Miller <davem@davemloft.net>
Cc: Jesse Gross <jesse@nicira.com>
Signed-off-by: Cong Wang <amwang@redhat.com>
Acked-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Merge second patch-bomb from Andrew Morton:
- A little DM fix
- the MM queue
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (154 commits)
ksm: allocate roots when needed
mm: cleanup "swapcache" in do_swap_page
mm,ksm: swapoff might need to copy
mm,ksm: FOLL_MIGRATION do migration_entry_wait
ksm: shrink 32-bit rmap_item back to 32 bytes
ksm: treat unstable nid like in stable tree
ksm: add some comments
tmpfs: fix mempolicy object leaks
tmpfs: fix use-after-free of mempolicy object
mm/fadvise.c: drain all pagevecs if POSIX_FADV_DONTNEED fails to discard all pages
mm: export mmu notifier invalidates
mm: accelerate mm_populate() treatment of THP pages
mm: use long type for page counts in mm_populate() and get_user_pages()
mm: accurately document nr_free_*_pages functions with code comments
HWPOISON: change order of error_states[]'s elements
HWPOISON: fix misjudgement of page_action() for errors on mlocked pages
memcg: stop warning on memcg_propagate_kmem
net: change type of virtio_chan->p9_max_pages
vmscan: change type of vm_total_pages to unsigned long
fs/nfsd: change type of max_delegations, nfsd_drc_max_mem and nfsd_drc_mem_used
...
It is a pity to have MAX_NUMNODES+MAX_NUMNODES tree roots statically
allocated, particularly when very few users will ever actually tune
merge_across_nodes 0 to use more than 1+1 of those trees. Not a big
deal (only 16kB wasted on each machine with CONFIG_MAXSMP), but a pity.
Start off with 1+1 statically allocated, then if merge_across_nodes is
ever tuned, allocate for nr_node_ids+nr_node_ids. Do not attempt to
free up the extra if it's tuned back, that would be a waste of effort.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Petr Holasek <pholasek@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Izik Eidus <izik.eidus@ravellosystems.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I dislike the way in which "swapcache" gets used in do_swap_page():
there is always a page from swapcache there (even if maybe uncached by
the time we lock it), but tests are made according to "swapcache".
Rework that with "page != swapcache", as has been done in unuse_pte().
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Petr Holasek <pholasek@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Izik Eidus <izik.eidus@ravellosystems.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Before establishing that KSM page migration was the cause of my
WARN_ON_ONCE(page_mapped(page))s, I suspected that they came from the
lack of a ksm_might_need_to_copy() in swapoff's unuse_pte() - which in
many respects is equivalent to faulting in a page.
In fact I've never caught that as the cause: but in theory it does at
least need the KSM_RUN_UNMERGE check in ksm_might_need_to_copy(), to
avoid bringing a KSM page back in when it's not supposed to be.
I intended to copy how it's done in do_swap_page(), but have a strong
aversion to how "swapcache" ends up being used there: rework it with
"page != swapcache".
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Petr Holasek <pholasek@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Izik Eidus <izik.eidus@ravellosystems.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In "ksm: remove old stable nodes more thoroughly" I said that I'd never
seen its WARN_ON_ONCE(page_mapped(page)). True at the time of writing,
but it soon appeared once I tried fuller tests on the whole series.
It turned out to be due to the KSM page migration itself: unmerge_and_
remove_all_rmap_items() failed to locate and replace all the KSM pages,
because of that hiatus in page migration when old pte has been replaced
by migration entry, but not yet by new pte. follow_page() finds no page
at that instant, but a KSM page reappears shortly after, without a
fault.
Add FOLL_MIGRATION flag, so follow_page() can do migration_entry_wait()
for KSM's break_cow(). I'd have preferred to avoid another flag, and do
it every time, in case someone else makes the same easy mistake; but did
not find another transgressor (the common get_user_pages() is of course
safe), and cannot be sure that every follow_page() caller is prepared to
sleep - ia64's xencomm_vtop()? Now, THP's wait_split_huge_page() can
already sleep there, since anon_vma locking was changed to mutex, but
maybe that's somehow excluded.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Petr Holasek <pholasek@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Izik Eidus <izik.eidus@ravellosystems.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Think of struct rmap_item as an extension of struct page (restricted to
MADV_MERGEABLE areas): there may be a lot of them, we need to keep them
small, especially on 32-bit architectures of limited lowmem.
Siting "int nid" after "unsigned int checksum" works nicely on 64-bit,
making no change to its 64-byte struct rmap_item; but bloats the 32-bit
struct rmap_item from (nicely cache-aligned) 32 bytes to 36 bytes, which
rounds up to 40 bytes once allocated from slab. We'd better avoid that.
Hey, I only just remembered that the anon_vma pointer in struct
rmap_item has no purpose until the rmap_item is hung from a stable tree
node (which has its own nid field); and rmap_item's nid field no purpose
than to say which tree root to tell rb_erase() when unlinking from an
unstable tree.
Double them up in a union. There's just one place where we set anon_vma
early (when we already hold mmap_sem): now we must remove tree_rmap_item
from its unstable tree there, before overwriting nid. No need to
spatter BUG()s around: we'd be seeing oopses if this were wrong.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Petr Holasek <pholasek@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Izik Eidus <izik.eidus@ravellosystems.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
An inconsistency emerged in reviewing the NUMA node changes to KSM: when
meeting a page from the wrong NUMA node in a stable tree, we say that
it's okay for comparisons, but not as a leaf for merging; whereas when
meeting a page from the wrong NUMA node in an unstable tree, we bail out
immediately.
Now, it might be that a wrong NUMA node in an unstable tree is more
likely to correlate with instablility (different content, with rbnode
now misplaced) than page migration; but even so, we are accustomed to
instablility in the unstable tree.
Without strong evidence for which strategy is generally better, I'd
rather be consistent with what's done in the stable tree: accept a page
from the wrong NUMA node for comparison, but not as a leaf for merging.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Petr Holasek <pholasek@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Izik Eidus <izik.eidus@ravellosystems.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Added slightly more detail to the Documentation of merge_across_nodes, a
few comments in areas indicated by review, and renamed get_ksm_page()'s
argument from "locked" to "lock_it". No functional change.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Petr Holasek <pholasek@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Izik Eidus <izik.eidus@ravellosystems.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix several mempolicy leaks in the tmpfs mount logic. These leaks are
slow - on the order of one object leaked per mount attempt.
Leak 1 (umount doesn't free mpol allocated in mount):
while true; do
mount -t tmpfs -o mpol=interleave,size=100M nodev /mnt
umount /mnt
done
Leak 2 (errors parsing remount options will leak mpol):
mount -t tmpfs -o size=100M nodev /mnt
while true; do
mount -o remount,mpol=interleave,size=x /mnt 2> /dev/null
done
umount /mnt
Leak 3 (multiple mpol per mount leak mpol):
while true; do
mount -t tmpfs -o mpol=interleave,mpol=interleave,size=100M nodev /mnt
umount /mnt
done
This patch fixes all of the above. I could have broken the patch into
three pieces but is seemed easier to review as one.
[akpm@linux-foundation.org: fix handling of mpol_parse_str() errors, per Hugh]
Signed-off-by: Greg Thelen <gthelen@google.com>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The tmpfs remount logic preserves filesystem mempolicy if the mpol=M
option is not specified in the remount request. A new policy can be
specified if mpol=M is given.
Before this patch remounting an mpol bound tmpfs without specifying
mpol= mount option in the remount request would set the filesystem's
mempolicy object to a freed mempolicy object.
To reproduce the problem boot a DEBUG_PAGEALLOC kernel and run:
# mkdir /tmp/x
# mount -t tmpfs -o size=100M,mpol=interleave nodev /tmp/x
# grep /tmp/x /proc/mounts
nodev /tmp/x tmpfs rw,relatime,size=102400k,mpol=interleave:0-3 0 0
# mount -o remount,size=200M nodev /tmp/x
# grep /tmp/x /proc/mounts
nodev /tmp/x tmpfs rw,relatime,size=204800k,mpol=??? 0 0
# note ? garbage in mpol=... output above
# dd if=/dev/zero of=/tmp/x/f count=1
# panic here
Panic:
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: [< (null)>] (null)
[...]
Oops: 0010 [#1] SMP DEBUG_PAGEALLOC
Call Trace:
mpol_shared_policy_init+0xa5/0x160
shmem_get_inode+0x209/0x270
shmem_mknod+0x3e/0xf0
shmem_create+0x18/0x20
vfs_create+0xb5/0x130
do_last+0x9a1/0xea0
path_openat+0xb3/0x4d0
do_filp_open+0x42/0xa0
do_sys_open+0xfe/0x1e0
compat_sys_open+0x1b/0x20
cstar_dispatch+0x7/0x1f
Non-debug kernels will not crash immediately because referencing the
dangling mpol will not cause a fault. Instead the filesystem will
reference a freed mempolicy object, which will cause unpredictable
behavior.
The problem boils down to a dropped mpol reference below if
shmem_parse_options() does not allocate a new mpol:
config = *sbinfo
shmem_parse_options(data, &config, true)
mpol_put(sbinfo->mpol)
sbinfo->mpol = config.mpol /* BUG: saves unreferenced mpol */
This patch avoids the crash by not releasing the mempolicy if
shmem_parse_options() doesn't create a new mpol.
How far back does this issue go? I see it in both 2.6.36 and 3.3. I did
not look back further.
Signed-off-by: Greg Thelen <gthelen@google.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rob van der Heij reported the following (paraphrased) on private mail.
The scenario is that I want to avoid backups to fill up the page
cache and purge stuff that is more likely to be used again (this is
with s390x Linux on z/VM, so I don't give it as much memory that
we don't care anymore). So I have something with LD_PRELOAD that
intercepts the close() call (from tar, in this case) and issues
a posix_fadvise() just before closing the file.
This mostly works, except for small files (less than 14 pages)
that remains in page cache after the face.
Unfortunately Rob has not had a chance to test this exact patch but the
test program below should be reproducing the problem he described.
The issue is the per-cpu pagevecs for LRU additions. If the pages are
added by one CPU but fadvise() is called on another then the pages
remain resident as the invalidate_mapping_pages() only drains the local
pagevecs via its call to pagevec_release(). The user-visible effect is
that a program that uses fadvise() properly is not obeyed.
A possible fix for this is to put the necessary smarts into
invalidate_mapping_pages() to globally drain the LRU pagevecs if a
pagevec page could not be discarded. The downside with this is that an
inode cache shrink would send a global IPI and memory pressure
potentially causing global IPI storms is very undesirable.
Instead, this patch adds a check during fadvise(POSIX_FADV_DONTNEED) to
check if invalidate_mapping_pages() discarded all the requested pages.
If a subset of pages are discarded it drains the LRU pagevecs and tries
again. If the second attempt fails, it assumes it is due to the pages
being mapped, locked or dirty and does not care. With this patch, an
application using fadvise() correctly will be obeyed but there is a
downside that a malicious application can force the kernel to send
global IPIs and increase overhead.
If accepted, I would like this to be considered as a -stable candidate.
It's not an urgent issue but it's a system call that is not working as
advertised which is weak.
The following test program demonstrates the problem. It should never
report that pages are still resident but will without this patch. It
assumes that CPU 0 and 1 exist.
int main() {
int fd;
int pagesize = getpagesize();
ssize_t written = 0, expected;
char *buf;
unsigned char *vec;
int resident, i;
cpu_set_t set;
/* Prepare a buffer for writing */
expected = FILESIZE_PAGES * pagesize;
buf = malloc(expected + 1);
if (buf == NULL) {
printf("ENOMEM\n");
exit(EXIT_FAILURE);
}
buf[expected] = 0;
memset(buf, 'a', expected);
/* Prepare the mincore vec */
vec = malloc(FILESIZE_PAGES);
if (vec == NULL) {
printf("ENOMEM\n");
exit(EXIT_FAILURE);
}
/* Bind ourselves to CPU 0 */
CPU_ZERO(&set);
CPU_SET(0, &set);
if (sched_setaffinity(getpid(), sizeof(set), &set) == -1) {
perror("sched_setaffinity");
exit(EXIT_FAILURE);
}
/* open file, unlink and write buffer */
fd = open("fadvise-test-file", O_CREAT|O_EXCL|O_RDWR);
if (fd == -1) {
perror("open");
exit(EXIT_FAILURE);
}
unlink("fadvise-test-file");
while (written < expected) {
ssize_t this_write;
this_write = write(fd, buf + written, expected - written);
if (this_write == -1) {
perror("write");
exit(EXIT_FAILURE);
}
written += this_write;
}
free(buf);
/*
* Force ourselves to another CPU. If fadvise only flushes the local
* CPUs pagevecs then the fadvise will fail to discard all file pages
*/
CPU_ZERO(&set);
CPU_SET(1, &set);
if (sched_setaffinity(getpid(), sizeof(set), &set) == -1) {
perror("sched_setaffinity");
exit(EXIT_FAILURE);
}
/* sync and fadvise to discard the page cache */
fsync(fd);
if (posix_fadvise(fd, 0, expected, POSIX_FADV_DONTNEED) == -1) {
perror("posix_fadvise");
exit(EXIT_FAILURE);
}
/* map the file and use mincore to see which parts of it are resident */
buf = mmap(NULL, expected, PROT_READ, MAP_SHARED, fd, 0);
if (buf == NULL) {
perror("mmap");
exit(EXIT_FAILURE);
}
if (mincore(buf, expected, vec) == -1) {
perror("mincore");
exit(EXIT_FAILURE);
}
/* Check residency */
for (i = 0, resident = 0; i < FILESIZE_PAGES; i++) {
if (vec[i])
resident++;
}
if (resident != 0) {
printf("Nr unexpected pages resident: %d\n", resident);
exit(EXIT_FAILURE);
}
munmap(buf, expected);
close(fd);
free(vec);
exit(EXIT_SUCCESS);
}
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reported-by: Rob van der Heij <rvdheij@gmail.com>
Tested-by: Rob van der Heij <rvdheij@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We at SGI have a need to address some very high physical address ranges
with our GRU (global reference unit), sometimes across partitioned
machine boundaries and sometimes with larger addresses than the cpu
supports. We do this with the aid of our own 'extended vma' module
which mimics the vma. When something (either unmap or exit) frees an
'extended vma' we use the mmu notifiers to clean them up.
We had been able to mimic the functions
__mmu_notifier_invalidate_range_start() and
__mmu_notifier_invalidate_range_end() by locking the per-mm lock and
walking the per-mm notifier list. But with the change to a global srcu
lock (static in mmu_notifier.c) we can no longer do that. Our module has
no access to that lock.
So we request that these two functions be exported.
Signed-off-by: Cliff Wickman <cpw@sgi.com>
Acked-by: Robin Holt <holt@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This change adds a follow_page_mask function which is equivalent to
follow_page, but with an extra page_mask argument.
follow_page_mask sets *page_mask to HPAGE_PMD_NR - 1 when it encounters
a THP page, and to 0 in other cases.
__get_user_pages() makes use of this in order to accelerate populating
THP ranges - that is, when both the pages and vmas arrays are NULL, we
don't need to iterate HPAGE_PMD_NR times to cover a single THP page (and
we also avoid taking mm->page_table_lock that many times).
Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use long type for page counts in mm_populate() so as to avoid integer
overflow when running the following test code:
int main(void) {
void *p = mmap(NULL, 0x100000000000, PROT_READ,
MAP_PRIVATE | MAP_ANON, -1, 0);
printf("p: %p\n", p);
mlockall(MCL_CURRENT);
printf("done\n");
return 0;
}
Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
nr_free_zone_pages(), nr_free_buffer_pages() and nr_free_pagecache_pages()
are horribly badly named, so accurately document them with code comments
in case of the misuse of them.
[akpm@linux-foundation.org: tweak comments]
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
error_states[] has two separate states "unevictable LRU page" and
"mlocked LRU page", and the former one has the higher priority now. But
because of that the latter one is rarely chosen because pages with
PageMlocked highly likely have PG_unevictable set. On the other hand,
PG_unevictable without PageMlocked is common for ramfs or SHM_LOCKed
shared memory, so reversing the priority of these two states helps us
clearly distinguish them.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Chen Gong <gong.chen@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
memory_failure() can't handle memory errors on mlocked pages correctly,
because page_action() judges such errors as ones on "unknown pages"
instead of ones on "unevictable LRU page" or "mlocked LRU page". In
order to determine page_state page_action() checks page flags at the
timing of the judgement, but such page flags are not the same with those
just after memory_failure() is called, because memory_failure() does
unmapping of the error pages before doing page_action(). This unmapping
changes the page state, especially page_remove_rmap() (called from
try_to_unmap_one()) clears PG_mlocked, so page_action() can't catch
mlocked pages after that.
With this patch, we store the page flag of the error page before doing
unmap, and (only) if the first check with page flags at the time decided
the error page is unknown, we do the second check with the stored page
flag. This implementation doesn't change error handling for the page
types for which the first check can determine the page state correctly.
[akpm@linux-foundation.org: tweak comments]
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Chen Gong <gong.chen@linux.intel.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Whilst I run the risk of a flogging for disloyalty to the Lord of Sealand,
I do have CONFIG_MEMCG=y CONFIG_MEMCG_KMEM not set, and grow tired of the
"mm/memcontrol.c:4972:12: warning: `memcg_propagate_kmem' defined but not
used [-Wunused-function]" seen in 3.8-rc: move the #ifdef outwards.
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Glauber Costa <glommer@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This member of struct virtio_chan is calculated from nr_free_buffer_pages
so change its type to unsigned long in case of overflow.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This variable is calculated from nr_free_pagecache_pages so
change its type to unsigned long.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The three variables are calculated from nr_free_buffer_pages so change
their types to unsigned long in case of overflow.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Thomas Petazzoni