With transparent hugepage support, handle_mm_fault() has to be careful
that a normal PMD has been established before handling a PTE fault.  To
achieve this, it used __pte_alloc() directly instead of pte_alloc_map as
pte_alloc_map is unsafe to run against a huge PMD.  pte_offset_map() is
called once it is known the PMD is safe.

pte_alloc_map() is smart enough to check if a PTE is already present
before calling __pte_alloc but this check was lost.  As a consequence,
PTEs may be allocated unnecessarily and the page table lock taken.  Thi
useless PTE does get cleaned up but it's a performance hit which is
visible in page_test from aim9.

This patch simply re-adds the check normally done by pte_alloc_map to
check if the PTE needs to be allocated before taking the page table lock.
The effect is noticable in page_test from aim9.

  AIM9
                  2.6.38-vanilla 2.6.38-checkptenone
  creat-clo      446.10 ( 0.00%)   424.47 (-5.10%)
  page_test       38.10 ( 0.00%)    42.04 ( 9.37%)
  brk_test        52.45 ( 0.00%)    51.57 (-1.71%)
  exec_test      382.00 ( 0.00%)   456.90 (16.39%)
  fork_test       60.11 ( 0.00%)    67.79 (11.34%)
  MMTests Statistics: duration
  Total Elapsed Time (seconds)                611.90    612.22

(While this affects 2.6.38, it is a performance rather than a functional
bug and normally outside the rules -stable.  While the big performance
differences are to a microbench, the difference in fork and exec
performance may be significant enough that -stable wants to consider the
patch)
Reported-by: Raz Ben Yehuda <raziebe@gmail.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: <stable@kernel.org>		[2.6.38.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In corner cases where softlockup watchdog is not setup successfully, the
relevant nmi perf event for hardlockup watchdog could be disabled, then
the status of the underlying hardware remains unchanged.

Also, if the kthread doesn't start then the hrtimer won't run and the
hardlockup detector will falsely fire.
Signed-off-by: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In some cases gcc >= 4.5.2 will optimize away current_thread_info().  To
prevent gcc from doing so the stack address has to be obtained via inline
asm.
Signed-off-by: Richard Weinberger <richard@nod.at>
Acked-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Make HoneyPot ProcFS depend on CONFIG_PROC_FS so that it will build.
Recommended by Christoph Hellwig.

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=33692Reported-by: Simon Danner <danner.simon@gmail.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This adds support for 64 bit atomic operations on 32 bit UML systems.  XFS
needs them since 2.6.38.

  $ make ARCH=um SUBARCH=i386
  ...
    LD      .tmp_vmlinux1
  fs/built-in.o: In function `xlog_regrant_reserve_log_space':
  xfs_log.c:(.text+0xd8584): undefined reference to `atomic64_read_386'
  xfs_log.c:(.text+0xd85ac): undefined reference to `cmpxchg8b_emu'
  ...

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=32812Reported-by: Martin Walch <walch.martin@web.de>
Tested-by: Martin Walch <walch.martin@web.de>
Cc: Martin Walch <walch.martin@web.de>
Cc: <stable@kernel.org> [2.6.38.x 084189a8: um: disable CONFIG_CMPXCHG_LOCAL]
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

PTE pages eat up memory just like anything else, but we do not account for
them in any way in the OOM scores.  They are also _guaranteed_ to get
freed up when a process is OOM killed, while RSS is not.
Reported-by: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: <stable@kernel.org>		[2.6.36+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Since 569b846d ("memcg: coalesce uncharge during unmap/truncate"), we do
batched (delayed) uncharge at truncation/unmap.  And since cdec2e42(memcg:
coalesce charging via percpu storage), we have percpu cache for
res_counter.

These changes improved performance of memory cgroup very much, but made
res_counter->usage usually have a bigger value than the actual value of
memory usage.  So, *.usage_in_bytes, which show res_counter->usage, are
not desirable for precise values of memory(and swap) usage anymore.

Instead of removing these files completely(because we cannot know
res_counter->usage without them), this patch updates the meaning of those
files.
Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The huge_memory.c THP page fault was allowed to run if vm_ops was null
(which would succeed for /dev/zero MAP_PRIVATE, as the f_op->mmap wouldn't
setup a special vma->vm_ops and it would fallback to regular anonymous
memory) but other THP logics weren't fully activated for vmas with vm_file
not NULL (/dev/zero has a not NULL vma->vm_file).

So this removes the vm_file checks so that /dev/zero also can safely use
THP (the other albeit safer approach to fix this bug would have been to
prevent the THP initial page fault to run if vm_file was set).

After removing the vm_file checks, this also makes huge_memory.c stricter
in khugepaged for the DEBUG_VM=y case.  It doesn't replace the vm_file
check with a is_pfn_mapping check (but it keeps checking for VM_PFNMAP
under VM_BUG_ON) because for a is_cow_mapping() mapping VM_PFNMAP should
only be allowed to exist before the first page fault, and in turn when
vma->anon_vma is null (so preventing khugepaged registration).  So I tend
to think the previous comment saying if vm_file was set, VM_PFNMAP might
have been set and we could still be registered in khugepaged (despite
anon_vma was not NULL to be registered in khugepaged) was too paranoid.
The is_linear_pfn_mapping check is also I think superfluous (as described
by comment) but under DEBUG_VM it is safe to stay.

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=33682Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: Caspar Zhang <bugs@casparzhang.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: <stable@kernel.org>		[2.6.38.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Azurit reports large increases in system time after 2.6.36 when running
Apache.  It was bisected down to a892e2d7 ("vfs: use kmalloc()
to allocate fdmem if possible").

That patch caused the vfs to use kmalloc() for very large allocations and
this is causing excessive work (and presumably excessive reclaim) within
the page allocator.

Fix it by falling back to vmalloc() earlier - when the allocation attempt
would have been considered "costly" by reclaim.
Reported-by: azurIt <azurit@pobox.sk>
Tested-by: azurIt <azurit@pobox.sk>
Acked-by: Changli Gao <xiaosuo@gmail.com>
Cc: Americo Wang <xiyou.wangcong@gmail.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/parisc-2.6:
  [PARISC] slub: fix panic with DISCONTIGMEM
  [PARISC] set memory ranges in N_NORMAL_MEMORY when onlined

* 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6:
  ACPI / PM: Avoid infinite recurrence while registering power resources
  PM / Wakeup: Fix initialization of wakeup-related device sysfs files

* 'spell-fix' of git://git.profusion.mobi/users/lucas/linux-2.6:
  Revert wrong fixes for common misspellings

* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: (42 commits)
  [media] media: vb2: correct queue initialization order
  [media] media: vb2: fix incorrect v4l2_buffer->flags handling
  [media] s5p-fimc: Add support for the buffer timestamps and sequence
  [media] s5p-fimc: Fix bytesperline and plane payload setup
  [media] s5p-fimc: Do not allow changing format after REQBUFS
  [media] s5p-fimc: Fix FIMC3 pixel limits on Exynos4
  [media] tda18271: update tda18271c2_rf_cal as per NXP's rev.04 datasheet
  [media] tda18271: update tda18271_rf_band as per NXP's rev.04 datasheet
  [media] tda18271: fix bad calculation of main post divider byte
  [media] tda18271: prog_cal and prog_tab variables should be s32, not u8
  [media] tda18271: fix calculation bug in tda18271_rf_tracking_filters_init
  [media] omap3isp: queue: Don't corrupt buf->npages when get_user_pages() fails
  [media] v4l: Don't register media entities for subdev device nodes
  [media] omap3isp: Don't increment node entity use count when poweron fails
  [media] omap3isp: lane shifter support
  [media] omap3isp: ccdc: support Y10/12, 8-bit bayer fmts
  [media] media: add missing 8-bit bayer formats and Y12
  [media] v4l: add V4L2_PIX_FMT_Y12 format
  cx23885: Fix stv0367 Kconfig dependency
  [media] omap3isp: Use isp xclk defines
  ...

Fix up trivial conflict (spelink errurs) in drivers/media/video/omap3isp/isp.c

These changes were incorrectly fixed by codespell. They were now
manually corrected.
Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>

The EXPERT menu list was recently broken by the insertion of a
kconfig symbol (EMBEDDED) at the beginning of the EXPERT list of
kconfig items.  Broken by:

  commit 6a108a14
  Author: David Rientjes <rientjes@google.com>
  Date:   Thu Jan 20 14:44:16 2011 -0800
    kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT

Restore the EXPERT menu list -- don't inject a symbol (EMBEDDED)
that does not depend on EXPERT into the list.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Peter Foley <pefoley2@verizon.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp:
  amd64_edac: Erratum #637 workaround
  amd64_edac: Factor in CC6 save area
  amd64_edac: Remove node interleave warning
  EDAC: Remove debugging output in scrub rate handling

* git://git.kernel.org/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog:
  watchdog: iTCO_wdt: TCO Watchdog patch for Intel Panther Point PCH

* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6:
  [S390] kvm-390: Let kernel exit SIE instruction on work
  [S390] dasd: check sense type in device change handler
  [S390] pfault: fix token handling
  [S390] qdio: reset error states immediately
  [S390] fix page table walk for changing page attributes
  [S390] prng: prevent access beyond end of stack
  [S390] dasd: fix race between open and offline

* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: cleanup error handling in inode.c
  Btrfs: put the right bio if we have an error
  Btrfs: free bitmaps properly when evicting the cache
  Btrfs: Free free_space item properly in btrfs_trim_block_group()
  btrfs: add missing spin_unlock to a rare exit path
  Btrfs: check return value of kmalloc()
  btrfs: fix wrong allocating flag when reading page
  Btrfs: fix missing mutex_unlock in btrfs_del_dir_entries_in_log()

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: do some plugging in the submit_bio threads

F15h CPUs may report a non-DRAM address when reporting an error address
belonging to a CC6 state save area. Add a workaround to detect this
condition and compute the actual DRAM address of the error as documented
in the Revision Guide for AMD Family 15h Models 00h-0Fh Processors.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>

F15h and later use a portion of DRAM as a CC6 storage area. BIOS
programs D18F1x[17C:140,7C:40] DRAM Base/Limit accordingly by
subtracting the storage area from the DRAM limit setting. However, in
order for edac to consider that part of DRAM too, we need to include it
into the per-node range.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>

This warning was wrongfully added for a normal condition - intlvsel
actually selects the destination node when node interleaving is enabled
and it is not a mismatch. For a detailed example, see section 2.8.10.2
"Node Interleaving" in F10h BKDG.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>

This patch adds the TCO Watchdog DeviceIDs for the Intel Panther Point PCH.
Signed-off-by: Seth Heasley <seth.heasley@intel.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

There is at least one BIOS with a DSDT containing a power resource
object with a _PR0 entry pointing back to that power resource.  In
consequence, while registering that power resource
acpi_bus_get_power_flags() sees that it depends on itself and tries
to register it again, which leads to an infinitely deep recurrence.
This problem was introduced by commit bf325f95
(ACPI / PM: Register power resource devices as soon as they are
needed).

To fix this problem use the observation that power resources cannot
be power manageable and prevent acpi_bus_get_power_flags() from
being called for power resource objects.

References: https://bugzilla.kernel.org/show_bug.cgi?id=31872Reported-and-tested-by: Pascal Dormeau <pdormeau@free.fr>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Len Brown <lenb@kernel.org>
Cc: stable@kernel.org

It turns out that some PCI devices are only found to be
wakeup-capable during registration, in which case, when
device_set_wakeup_capable() is called, device_is_registered() already
returns 'true' for the given device, but dpm_sysfs_add() hasn't been
called for it yet.  This leads to situations in which the device's
power.can_wakeup flag is not set as requested because of failing
wakeup_sysfs_add() and its wakeup-related sysfs files are not
created, although they should be present.  This is a post-2.6.38
regression introduced by commit cb8f51bd
(PM: Do not create wakeup sysfs files for devices that cannot wake
up).

To work around this problem initialize the device's power.entry
field to an empty list head and make device_set_wakeup_capable()
check if it is still empty before attempting to add the devices
wakeup-related sysfs files with wakeup_sysfs_add().  Namely, if
power.entry is still empty at this point, device_pm_add() hasn't been
called yet for the device and its wakeup-related files will be
created later, so device_set_wakeup_capable() doesn't have to create
them.
Reported-and-tested-by: Tino Keitel <tino.keitel@tikei.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>

* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
  CIFS: Fix memory over bound bug in cifs_parse_mount_options

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ecryptfs/ecryptfs-2.6:
  eCryptfs: Flush dirty pages in setattr
  eCryptfs: Handle failed metadata read in lookup
  eCryptfs: Add reference counting to lower files
  eCryptfs: dput dentries returned from dget_parent
  eCryptfs: Remove extra d_delete in ecryptfs_rmdir

Merge branch 'for-torvalds' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-stericsson

* 'for-torvalds' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-stericsson:
  rtc: fix coh901331 startup crash
  mach-ux500: fix i2c0 device setup regression

Now that the security modules can decide whether they support the
dcache RCU walk or not it's possible to make selinux a bit more
RCU friendly.  The SELinux AVC and security server access decision
code is RCU safe.  A specific piece of the LSM audit code may not
be RCU safe.

This patch makes the VFS RCU walk retry if it would hit the non RCU
safe chunk of code.  It will normally just work under RCU.  This is
done simply by passing the VFS RCU state as a flag down into the
avc_audit() code and returning ECHILD there if it would have an issue.
Based-on-patch-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Now that the whole dcache_hash_bucket crap is gone, go all the way and
also remove the weird locking layering violations for locking the hash
buckets.  Add hlist_bl_lock/unlock helpers to move the locking into the
list abstraction instead of requiring each caller to open code it.
After all allowing for the bit locks is the whole point of these helpers
over the plain hlist variant.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When we are waiting for the bit-lock to be released, and are looping
over the 'cpu_relax()' should not be doing anything else - otherwise we
miss the point of trying to do the whole 'cpu_relax()'.

Do the preemption enable/disable around the loop, rather than inside of
it.

Noticed when I was looking at the code generation for the dcache
__d_drop usage, and the code just looked very odd.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

After 57db4e8d changed eCryptfs to
write-back caching, eCryptfs page writeback updates the lower inode
times due to the use of vfs_write() on the lower file.

To preserve inode metadata changes, such as 'cp -p' does with
utimensat(), we need to flush all dirty pages early in
ecryptfs_setattr() so that the user-updated lower inode metadata isn't
clobbered later in writeback.

https://bugzilla.kernel.org/show_bug.cgi?id=33372Reported-by: Rocko <rockorequin@hotmail.com>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>

When failing to read the lower file's crypto metadata during a lookup,
eCryptfs must continue on without throwing an error. For example, there
may be a plaintext file in the lower mount point that the user wants to
delete through the eCryptfs mount.

If an error is encountered while reading the metadata in lookup(), the
eCryptfs inode's size could be incorrect. We must be sure to reread the
plaintext inode size from the metadata when performing an open() or
setattr(). The metadata is already being read in those paths, so this
adds minimal performance overhead.

This patch introduces a flag which will track whether or not the
plaintext inode size has been read so that an incorrect i_size can be
fixed in the open() or setattr() paths.

https://bugs.launchpad.net/bugs/509180

Cc: <stable@kernel.org>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>

The error processing of several places is changed like setting the
error number only at the error.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

In btrfs_submit_direct_hook if the first btrfs_map_block fails we need to put
the orig_bio, not bio.
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>