Fix a typo that used the wrong bitmask for the pg.seed calculation.  This
is normally unnoticed because in most cases pg_num == pgp_num.  It is, however,
a bug that is easily corrected.

CC: stable@vger.kernel.org
Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <alex.elder@linary.org>

When a request returns an error, the driver needs to report the entire
extent of the request as completed.  Writes already did this, since
they always set xferred = length, but reads were skipping that step if
an error other than -ENOENT occurred.  Instead, rbd would end up
passing 0 xferred to blk_end_request(), which would always report
needing more data.  This resulted in an assert failing when more data
was required by the block layer, but all the object requests were
done:

[ 1868.719077] rbd: obj_request read result -108 xferred 0
[ 1868.719077]
[ 1868.719518] end_request: I/O error, dev rbd1, sector 0
[ 1868.719739]
[ 1868.719739] Assertion failure in rbd_img_obj_callback() at line 1736:
[ 1868.719739]
[ 1868.719739]   rbd_assert(more ^ (which == img_request->obj_request_count));

Without this assert, reads that hit errors would hang forever, since
the block layer considered them incomplete.

Fixes: http://tracker.ceph.com/issues/5647
CC: stable@vger.kernel.org  # v3.10
Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
Reviewed-by: Alex Elder <alex.elder@linaro.org>

Following we will begin to add memcg dirty page accounting around
__set_page_dirty_{buffers,nobuffers} in vfs layer, so we'd better use vfs interface to
avoid exporting those details to filesystems.

Since vfs set_page_dirty() should be called under page lock, here we don't need elaborate
codes to handle racy anymore, and two WARN_ON() are added to detect such exceptions.
Thanks very much for Sage and Yan Zheng's coaching!

I tested it in a two server's ceph environment that one is client and the other is
mds/osd/mon, and run the following fsx test from xfstests:

  ./fsx   1MB -N 50000 -p 10000 -l 1048576
  ./fsx  10MB -N 50000 -p 10000 -l 10485760
  ./fsx 100MB -N 50000 -p 10000 -l 104857600

The fsx does lots of mmap-read/mmap-write/truncate operations and the tests completed
successfully without triggering any of WARN_ON.
Signed-off-by: Sha Zhengju <handai.szj@taobao.com>
Reviewed-by: Sage Weil <sage@inktank.com>

For sync_read/write, it may do multi stripe operations.If one of those
met erro, we return the former successed size rather than a error value.
There is a exception for write-operation met -EOLDSNAPC.If this occur,we
retry the whole write again.
Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>

cephfs . show_layout
>layyout.data_pool:     0
>layout.object_size:   4194304
>layout.stripe_unit:   4194304
>layout.stripe_count:  1

TestA:
>dd if=/dev/urandom of=test bs=1M count=2 oflag=direct
>dd if=/dev/urandom of=test bs=1M count=2 seek=4  oflag=direct
>dd if=test of=/dev/null bs=6M count=1 iflag=direct
The messages from func striped_read are:
ceph:           file.c:350  : striped_read 0~6291456 (read 0) got 2097152 HITSTRIPE SHORT
ceph:           file.c:350  : striped_read 2097152~4194304 (read 2097152) got 0 HITSTRIPE SHORT
ceph:           file.c:381  : zero tail 4194304
ceph:           file.c:390  : striped_read returns 6291456
The hole of file is from 2M--4M.But actualy it zero the last 4M include
the last 2M area which isn't a hole.
Using this patch, the messages are:
ceph:           file.c:350  : striped_read 0~6291456 (read 0) got 2097152 HITSTRIPE SHORT
ceph:           file.c:358  :  zero gap 2097152 to 4194304
ceph:           file.c:350  : striped_read 4194304~2097152 (read 4194304) got 2097152
ceph:           file.c:384  : striped_read returns 6291456

TestB:
>echo majianpeng > test
>dd if=test of=/dev/null bs=2M count=1 iflag=direct
The messages are:
ceph:           file.c:350  : striped_read 0~6291456 (read 0) got 11 HITSTRIPE SHORT
ceph:           file.c:350  : striped_read 11~6291445 (read 11) got 0 HITSTRIPE SHORT
ceph:           file.c:390  : striped_read returns 11
For this case,it did once more striped_read.It's no meaningless.
Using this patch, the message are:
ceph:           file.c:350  : striped_read 0~6291456 (read 0) got 11 HITSTRIPE SHORT
ceph:           file.c:384  : striped_read returns 11

Big thanks to Yan Zheng for the patch.
Reviewed-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>

Cleanup in handle_cap_grant().
Signed-off-by: Li Wang <liwang@ubuntukylin.com>
Reviewed-by: Sage Weil <sage@inktank.com>

create_singlethread_workqueue() returns NULL on error, and it doesn't
return ERR_PTRs.

I tweaked the error handling a little to be consistent with earlier in
the function.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Sage Weil <sage@inktank.com>

There are two places where we read "nr_maps" if both of them are set to
zero then we would hit a NULL dereference here.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Sage Weil <sage@inktank.com>

We've tried to fix the error paths in this function before, but there
is still a hidden goto in the ceph_decode_need() macro which goes to the
wrong place.  We need to release the "req" and unlock a mutex before
returning.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Sage Weil <sage@inktank.com>

We need to use do_div to divide by a 64-bit value.
Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>

This patch implements fallocate and punch hole support for Ceph kernel client.
Signed-off-by: Li Wang <liwang@ubuntukylin.com>
Signed-off-by: Yunchuan Wen <yunchuanwen@ubuntukylin.com>

ceph_check_caps() requests new max size only when there is Fw cap.
If we call check_max_size() while there is no Fw cap. It updates
i_wanted_max_size and calls ceph_check_caps(), but ceph_check_caps()
does nothing. Later when Fw cap is issued, we call check_max_size()
again. But i_wanted_max_size is equal to 'endoff' at this time, so
check_max_size() doesn't call ceph_check_caps() and we end up with
waiting for the new max size forever.

The fix is duplicate ceph_check_caps()'s "request max size" code in
check_max_size(), and make try_get_cap_refs() wait for the Fw cap
before retry requesting new max size.

This patch also removes the "endoff > (inode->i_size << 1)" check
in check_max_size(). It's useless because there is no corresponding
logic in ceph_check_caps().
Reviewed-by: Sage Weil <sage@inktank.com>
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>

I encountered below deadlock when running fsstress

wmtruncate work      truncate                 MDS
---------------  ------------------  --------------------------
                   lock i_mutex
                                      <- truncate file
lock i_mutex (blocked)
                                      <- revoking Fcb (filelock to MIX)
                   send request ->
                                         handle request (xlock filelock)

At the initial time, there are some dirty pages in the page cache.
When the kclient receives the truncate message, it reduces inode size
and creates some 'out of i_size' dirty pages. wmtruncate work can't
truncate these dirty pages because it's blocked by the i_mutex. Later
when the kclient receives the cap message that revokes Fcb caps, It
can't flush all dirty pages because writepages() only flushes dirty
pages within the inode size.

When the MDS handles the 'truncate' request from kclient, it waits
for the filelock to become stable. But the filelock is stuck in
unstable state because it can't finish revoking kclient's Fcb caps.

The truncate pagecache locking has already caused lots of trouble
for use. I think it's time simplify it by introducing a new mutex.
We use the new mutex to prevent concurrent truncate_inode_pages().
There is no need to worry about race between buffered write and
truncate_inode_pages(), because our "get caps" mechanism prevents
them from concurrent execution.
Reviewed-by: Sage Weil <sage@inktank.com>
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>

The invalidatepage code bails if it encounters a non-zero page offset. The
current logic that does is non-obvious with multiple if statements.

This should be logically and functionally equivalent.
Signed-off-by: Milosz Tanski <milosz@adfin.com>
Reviewed-by: Sage Weil <sage@inktank.com>

Merge a bunch of fixes from Andrew Morton.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  fs/proc/task_mmu.c: fix buffer overflow in add_page_map()
  arch: *: Kconfig: add "kernel/Kconfig.freezer" to "arch/*/Kconfig"
  ocfs2: fix null pointer dereference in ocfs2_dir_foreach_blk_id()
  x86 get_unmapped_area(): use proper mmap base for bottom-up direction
  ocfs2: fix NULL pointer dereference in ocfs2_duplicate_clusters_by_page
  ocfs2: Revert 40bd62eb to avoid regression in extended allocation
  drivers/rtc/rtc-stmp3xxx.c: provide timeout for potentially endless loop polling a HW bit
  hugetlb: fix lockdep splat caused by pmd sharing
  aoe: adjust ref of head for compound page tails
  microblaze: fix clone syscall
  mm: save soft-dirty bits on file pages
  mm: save soft-dirty bits on swapped pages
  memcg: don't initialize kmem-cache destroying work for root caches

Recently we met quite a lot of random kernel panic issues after enabling
CONFIG_PROC_PAGE_MONITOR.  After debuggind we found this has something
to do with following bug in pagemap:

In struct pagemapread:

  struct pagemapread {
      int pos, len;
      pagemap_entry_t *buffer;
      bool v2;
  };

pos is number of PM_ENTRY_BYTES in buffer, but len is the size of
buffer, it is a mistake to compare pos and len in add_page_map() for
checking buffer is full or not, and this can lead to buffer overflow and
random kernel panic issue.

Correct len to be total number of PM_ENTRY_BYTES in buffer.

[akpm@linux-foundation.org: document pagemapread.pos and .len units, fix PM_ENTRY_BYTES definition]
Signed-off-by: Yonghua Zheng <younghua.zheng@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>

All architectures include "kernel/Kconfig.freezer" except three left, so
let them include it too, or 'allmodconfig' will report error.

The related errors: (with allmodconfig for openrisc):

    CC      kernel/cgroup_freezer.o
  kernel/cgroup_freezer.c: In function 'freezer_css_online':
  kernel/cgroup_freezer.c:133:15: error: 'system_freezing_cnt' undeclared (first use in this function)
  kernel/cgroup_freezer.c:133:15: note: each undeclared identifier is reported only once for each function it appears in
  kernel/cgroup_freezer.c: In function 'freezer_css_offline':
  kernel/cgroup_freezer.c:157:15: error: 'system_freezing_cnt' undeclared (first use in this function)
  kernel/cgroup_freezer.c: In function 'freezer_attach':
  kernel/cgroup_freezer.c:200:4: error: implicit declaration of function 'freeze_task'
  kernel/cgroup_freezer.c: In function 'freezer_apply_state':
  kernel/cgroup_freezer.c:371:16: error: 'system_freezing_cnt' undeclared (first use in this function)
Signed-off-by: Chen Gang <gang.chen@asianux.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix a NULL pointer deference while removing an empty directory, which
was introduced by commit 3704412b ("[readdir] convert ocfs2").

  BUG: unable to handle kernel NULL pointer dereference at (null)
  IP: [<(null)>]           (null)
  PGD 6da85067 PUD 6da89067 PMD 0
  Oops: 0010 [#1] SMP
  CPU: 0 PID: 6564 Comm: rmdir Tainted: G           O 3.11.0-rc1 #4
  RIP: 0010:[<0000000000000000>]  [<          (null)>]           (null)
  Call Trace:
    ocfs2_dir_foreach+0x49/0x50 [ocfs2]
    ocfs2_empty_dir+0x12c/0x3e0 [ocfs2]
    ocfs2_unlink+0x56e/0xc10 [ocfs2]
    vfs_rmdir+0xd5/0x140
    do_rmdir+0x1cb/0x1e0
    SyS_rmdir+0x16/0x20
    system_call_fastpath+0x16/0x1b
  Code:  Bad RIP value.
  RIP  [<          (null)>]           (null)
  RSP <ffff88006daddc10>
  CR2: 0000000000000000

[dan.carpenter@oracle.com: fix pointer math]
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reported-by: David Weber <wb@munzinger.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When the stack is set to unlimited, the bottomup direction is used for
mmap-ings but the mmap_base is not used and thus effectively renders
ASLR for mmapings along with PIE useless.

Cc: Michel Lespinasse <walken@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Sendroiu <molecula2788@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>

Since ocfs2_cow_file_pos will invoke ocfs2_refcount_icow with a NULL as
the struct file pointer, it finally result in a null pointer dereference
in ocfs2_duplicate_clusters_by_page.

This patch replace file pointer with inode pointer in
cow_duplicate_clusters to fix this issue.

[jeff.liu@oracle.com: rebased patch against linux-next tree]
Signed-off-by: Tiger Yang <tiger.yang@oracle.com>
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Acked-by: Tao Ma <tm@tao.ma>
Tested-by: David Weber <wb@munzinger.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Revert commit 40bd62eb ("fs/ocfs2/journal.h: add bits_wanted while
calculating credits in ocfs2_calc_extend_credits").

Unfortunately this change broke fallocate even if there is insufficient
disk space for the preallocation, which is a serious problem.

  # df -h
  /dev/sda8        22G  1.2G   21G   6% /ocfs2
  # fallocate -o 0 -l 200M /ocfs2/testfile
  fallocate: /ocfs2/test: fallocate failed: No space left on device

and a kernel warning:

  CPU: 3 PID: 3656 Comm: fallocate Tainted: G        W  O 3.11.0-rc3 #2
  Call Trace:
    dump_stack+0x77/0x9e
    warn_slowpath_common+0xc4/0x110
    warn_slowpath_null+0x2a/0x40
    start_this_handle+0x6c/0x640 [jbd2]
    jbd2__journal_start+0x138/0x300 [jbd2]
    jbd2_journal_start+0x23/0x30 [jbd2]
    ocfs2_start_trans+0x166/0x300 [ocfs2]
    __ocfs2_extend_allocation+0x38f/0xdb0 [ocfs2]
    ocfs2_allocate_unwritten_extents+0x3c9/0x520
    __ocfs2_change_file_space+0x5e0/0xa60 [ocfs2]
    ocfs2_fallocate+0xb1/0xe0 [ocfs2]
    do_fallocate+0x1cb/0x220
    SyS_fallocate+0x6f/0xb0
    system_call_fastpath+0x16/0x1b
  JBD2: fallocate wants too many credits (51216 > 4381)
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Cc: Goldwyn Rodrigues <rgoldwyn@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

It's always a bad idea to poll on HW bits without a timeout.

The i.MX28 RTC can be easily brought into a state in which the RTC is
not running (until after a power-on-reset) and thus the status bits
which are polled in the driver won't ever change.

This patch prevents the kernel from getting stuck in this case.
Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Dave has reported the following lockdep splat:

  =================================
  [ INFO: inconsistent lock state ]
  3.11.0-rc1+ #9 Not tainted
  ---------------------------------
  inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-W} usage.
  kswapd0/49 [HC0[0]:SC0[0]:HE1:SE1] takes:
   (&mapping->i_mmap_mutex){+.+.?.}, at: [<c114971b>] page_referenced+0x87/0x5e3
  {RECLAIM_FS-ON-W} state was registered at:
     mark_held_locks+0x81/0xe7
     lockdep_trace_alloc+0x5e/0xbc
     __alloc_pages_nodemask+0x8b/0x9b6
     __get_free_pages+0x20/0x31
     get_zeroed_page+0x12/0x14
     __pmd_alloc+0x1c/0x6b
     huge_pmd_share+0x265/0x283
     huge_pte_alloc+0x5d/0x71
     hugetlb_fault+0x7c/0x64a
     handle_mm_fault+0x255/0x299
     __do_page_fault+0x142/0x55c
     do_page_fault+0xd/0x16
     error_code+0x6c/0x74
  irq event stamp: 3136917
  hardirqs last  enabled at (3136917):  _raw_spin_unlock_irq+0x27/0x50
  hardirqs last disabled at (3136916):  _raw_spin_lock_irq+0x15/0x78
  softirqs last  enabled at (3136180):  __do_softirq+0x137/0x30f
  softirqs last disabled at (3136175):  irq_exit+0xa8/0xaa
  other info that might help us debug this:
   Possible unsafe locking scenario:
         CPU0
         ----
    lock(&mapping->i_mmap_mutex);
    <Interrupt>
      lock(&mapping->i_mmap_mutex);

  *** DEADLOCK ***
  no locks held by kswapd0/49.

  stack backtrace:
  CPU: 1 PID: 49 Comm: kswapd0 Not tainted 3.11.0-rc1+ #9
  Hardware name: Dell Inc.                 Precision WorkStation 490    /0DT031, BIOS A08 04/25/2008
  Call Trace:
    dump_stack+0x4b/0x79
    print_usage_bug+0x1d9/0x1e3
    mark_lock+0x1e0/0x261
    __lock_acquire+0x623/0x17f2
    lock_acquire+0x7d/0x195
    mutex_lock_nested+0x6c/0x3a7
    page_referenced+0x87/0x5e3
    shrink_page_list+0x3d9/0x947
    shrink_inactive_list+0x155/0x4cb
    shrink_lruvec+0x300/0x5ce
    shrink_zone+0x53/0x14e
    kswapd+0x517/0xa75
    kthread+0xa8/0xaa
    ret_from_kernel_thread+0x1b/0x28

which is a false positive caused by hugetlb pmd sharing code which
allocates a new pmd from withing mapping->i_mmap_mutex.  If this
allocation causes reclaim then the lockdep detector complains that we
might self-deadlock.

This is not correct though, because hugetlb pages are not reclaimable so
their mapping will be never touched from the reclaim path.

The patch tells lockup detector that hugetlb i_mmap_mutex is special by
assigning it a separate lockdep class so it won't report possible
deadlocks on unrelated mappings.

[peterz@infradead.org: comment for annotation]
Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix a BUG which can trigger when direct-IO is used with AOE.

As discussed previously, the fact that some users of the block layer
provide bios that point to pages with a zero _count means that it is not
OK for the network layer to do a put_page on the skb frags during an
skb_linearize, so the aoe driver gets a reference to pages in bios and
puts the reference before ending the bio.  And because it cannot use
get_page on a page with a zero _count, it manipulates the value
directly.

It is not OK to increment the _count of a compound page tail, though,
since the VM layer will VM_BUG_ON a non-zero _count.  Block users that
do direct I/O can result in the aoe driver seeing compound page tails in
bios.  In that case, the same logic works as long as the head of the
compound page is used instead of the tails.  This patch handles compound
pages and does not BUG.

It relies on the block layer user leaving the relationship between the
page tail and its head alone for the duration between the submission of
the bio and its completion, whether successful or not.
Signed-off-by: Ed Cashin <ecashin@coraid.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix inadvertent breakage in the clone syscall ABI for Microblaze that
was introduced in commit f3268edb ("microblaze: switch to generic
fork/vfork/clone").

The Microblaze syscall ABI for clone takes the parent tid address in the
4th argument; the third argument slot is used for the stack size.  The
incorrectly-used CLONE_BACKWARDS type assigned parent tid to the 3rd
slot.

This commit restores the original ABI so that existing userspace libc
code will work correctly.

All kernel versions from v3.8-rc1 were affected.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Andy reported that if file page get reclaimed we lose the soft-dirty bit
if it was there, so save _PAGE_BIT_SOFT_DIRTY bit when page address get
encoded into pte entry.  Thus when #pf happens on such non-present pte
we can restore it back.
Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Andy Lutomirski reported that if a page with _PAGE_SOFT_DIRTY bit set
get swapped out, the bit is getting lost and no longer available when
pte read back.

To resolve this we introduce _PTE_SWP_SOFT_DIRTY bit which is saved in
pte entry for the page being swapped out.  When such page is to be read
back from a swap cache we check for bit presence and if it's there we
clear it and restore the former _PAGE_SOFT_DIRTY bit back.

One of the problem was to find a place in pte entry where we can save
the _PTE_SWP_SOFT_DIRTY bit while page is in swap.  The _PAGE_PSE was
chosen for that, it doesn't intersect with swap entry format stored in
pte.
Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

struct memcg_cache_params has a union.  Different parts of this union
are used for root and non-root caches.  A part with destroying work is
used only for non-root caches.

I fixed the same problem in another place v3.9-rc1-16204-gf101a946, but
didn't notice this one.

This patch fixes the kernel panic:

[   46.848187] BUG: unable to handle kernel paging request at 000000fffffffeb8
[   46.849026] IP: [<ffffffff811a484c>] kmem_cache_destroy_memcg_children+0x6c/0xc0
[   46.849092] PGD 0
[   46.849092] Oops: 0000 [#1] SMP
...
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Cc: Glauber Costa <glommer@openvz.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: <stable@vger.kernel.org>    [3.9.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull scheduler fixes from Ingo Molnar:
 "Docbook fixes that make 99% of the diffstat, plus a oneliner fix"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Ensure update_cfs_shares() is called for parents of continuously-running tasks
  sched: Fix some kernel-doc warnings

Pull perf fixes from Ingo Molnar:
 "Two small fixlets"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86: Add Haswell ULT model number used in Macbook Air and other systems
  perf/x86: Fix intel QPI uncore event definitions

Fix constraint check in armpmu_map_hw_event().
Reported-and-tested-by: Vince Weaver <vincent.weaver@maine.edu>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This is only theoretical, but after try_to_wake_up(p) was changed
to check p->state under p->pi_lock the code like

	__set_current_state(TASK_INTERRUPTIBLE);
	schedule();

can miss a signal. This is the special case of wait-for-condition,
it relies on try_to_wake_up/schedule interaction and thus it does
not need mb() between __set_current_state() and if(signal_pending).

However, this __set_current_state() can move into the critical
section protected by rq->lock, now that try_to_wake_up() takes
another lock we need to ensure that it can't be reordered with
"if (signal_pending(current))" check inside that section.

The patch is actually one-liner, it simply adds smp_wmb() before
spin_lock_irq(rq->lock). This is what try_to_wake_up() already
does by the same reason.

We turn this wmb() into the new helper, smp_mb__before_spinlock(),
for better documentation and to allow the architectures to change
the default implementation.

While at it, kill smp_mb__after_lock(), it has no callers.

Perhaps we can also add smp_mb__before/after_spinunlock() for
prepare_to_wait().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull CIFS fixes from Steve French:
 "A set of small cifs fixes, including 3 relating to symlink handling"

* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: don't instantiate new dentries in readdir for inodes that need to be revalidated immediately
  cifs: set sb->s_d_op before calling d_make_root()
  cifs: fix bad error handling in crypto code
  cifs: file: initialize oparms.reconnect before using it
  Do not attempt to do cifs operations reading symlinks with SMB2
  cifs: extend the buffer length enought for sprintf() using

Pull more ext4 bugfixes from Ted Ts'o:
 "A number of miscellaneous ext4 bugs fixes for v3.11, including a fix
  so that if ext4 is built as a module, to allow it to be unloaded"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: flush the extent status cache during EXT4_IOC_SWAP_BOOT
  ext4: fix mount/remount error messages for incompatible mount options
  ext4: allow the mount options nodelalloc and data=journal

Pull w/w mutex deadlock injection fix from Ingo Molnar.

This bug made the CONFIG_DEBUG_WW_MUTEX_SLOWPATH=y option largely
useless, but wouldn't affect normal users.

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  mutex: Fix w/w mutex deadlock injection

Previously we weren't swapping only some of the extent_status LRU
fields during the processing of the EXT4_IOC_SWAP_BOOT ioctl.  The
much safer thing to do is to just completely flush the extent status
tree when doing the swap.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Zheng Liu <gnehzuil.liu@gmail.com>
Cc: stable@vger.kernel.org

This one was missed earlier.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1376007983-31616-1-git-send-email-andi@firstfloor.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

Pull SCSI fixes from James Bottomley:
 "This is three bug fixes: An fnic warning caused by sleeping under a
  lock, a major regression with our updated WRITE SAME/UNMAP logic which
  caused tons of USB devices (and one RAID card) to cease to function
  and a megaraid_sas firmware initialisation problem which causes kdump
  failures"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  [SCSI] Don't attempt to send extended INQUIRY command if skip_vpd_pages is set
  [SCSI] fnic: BUG: sleeping function called from invalid context during probe
  [SCSI] megaraid_sas: megaraid_sas driver init fails in kdump kernel