The "DIV_ROUND_UP(size, PAGE_SIZE)" operation can overflow if "size" is
more than ULLONG_MAX - PAGE_SIZE.

Link: http://lkml.kernel.org/r/20170322111950.GA11279@mwanda


Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Jorgen Hansen <jhansen@vmware.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When I was running my testcase which may block hundreds of threads on fs
locks, I got lockup due to output from debug_show_all_locks() added by
commit b2d4c2ed ("locking/hung_task: Show all locks").

For example, if 1000 threads were blocked in TASK_UNINTERRUPTIBLE state
and 500 out of 1000 threads hold some lock, debug_show_all_locks() from
for_each_process_thread() loop will report locks held by 500 threads for
1000 times.  This is a too much noise.

In order to make sure rcu_lock_break() is called frequently, we should
avoid calling debug_show_all_locks() from for_each_process_thread() loop
because debug_show_all_locks() effectively calls for_each_process_thread()
loop.  Let's defer calling debug_show_all_locks() till before panic() or
leaving for_each_process_thread() loop.

Link: http://lkml.kernel.org/r/1489296834-60436-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp


Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add a top-level Makefile help target for Userspace tools.

Also make each help "heading" end with a colon ':'.

Link: http://lkml.kernel.org/r/55c986ff-3966-3e47-2984-7349da2cce51@infradead.org


Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

jiffies_64 is defined in kernel/time/timer.c with
____cacheline_aligned_in_smp, however this macro is not part of the
declaration of jiffies and jiffies_64 in jiffies.h.

As a result clang generates the following warning:

  kernel/time/timer.c:57:26: error: section does not match previous declaration [-Werror,-Wsection]
  __visible u64 jiffies_64 __cacheline_aligned_in_smp = INITIAL_JIFFIES;
                           ^
  include/linux/cache.h:39:36: note: expanded from macro '__cacheline_aligned_in_smp'
                                     ^
  include/linux/cache.h:34:4: note: expanded from macro '__cacheline_aligned'
                   __section__(".data..cacheline_aligned")))
                   ^
  include/linux/jiffies.h:77:12: note: previous attribute is here
  extern u64 __jiffy_data jiffies_64;
             ^
  include/linux/jiffies.h:70:38: note: expanded from macro '__jiffy_data'

Link: http://lkml.kernel.org/r/20170403190200.70273-1-mka@chromium.org


Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Cc: "Jason A . Donenfeld" <Jason@zx2c4.com>
Cc: Grant Grundler <grundler@chromium.org>
Cc: Michael Davidson <md@google.com>
Cc: Greg Hackmann <ghackmann@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Moving from get_user_pages() to get_user_pages_unlocked() simplifies the
code and takes advantage of VM_FAULT_RETRY functionality when faulting
in pages.

Link: http://lkml.kernel.org/r/20161101194332.23961-1-lstoakes@gmail.com


Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Mihai Caraman <mihai.caraman@freescale.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

do_proc_dointvec_jiffies_conv() uses LONG_MAX/HZ as the max value to
avoid overflow.  But actually the *valp is int type, so it still causes
overflow.

For example,

  echo 2147483647 > ./sys/net/ipv4/tcp_keepalive_time

Then,

  cat ./sys/net/ipv4/tcp_keepalive_time

The output is "-1", it is not expected.

Now use INT_MAX/HZ as the max value instead LONG_MAX/HZ to fix it.

Link: http://lkml.kernel.org/r/1490109532-9228-1-git-send-email-fgao@ikuai8.com


Signed-off-by: Gao Feng <fgao@ikuai8.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Coccinelle emits this warning:

  WARNING: casting value returned by memory allocation function to (struct proc_inode *) is useless.

Remove unnecessary cast.

Link: http://lkml.kernel.org/r/1487745720-16967-1-git-send-email-me@tobin.cc


Signed-off-by: Tobin C. Harding <me@tobin.cc>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The main goal of direct compaction is to form a high-order page for
allocation, but it should also help against long-term fragmentation when
possible.

Most lower-than-pageblock-order compactions are for non-movable
allocations, which means that if we compact in a movable pageblock and
terminate as soon as we create the high-order page, it's unlikely that
the fallback heuristics will claim the whole block.  Instead there might
be a single unmovable page in a pageblock full of movable pages, and the
next unmovable allocation might pick another pageblock and increase
long-term fragmentation.

To help against such scenarios, this patch changes the termination
criteria for compaction so that the current pageblock is finished even
though the high-order page already exists.  Note that it might be
possible that the high-order page formed elsewhere in the zone due to
parallel activity, but this patch doesn't try to detect that.

This is only done with sync compaction, because async compaction is
limited to pageblock of the same migratetype, where it cannot result in
a migratetype fallback.  (Async compaction also eagerly skips
order-aligned blocks where isolation fails, which is against the goal of
migrating away as much of the pageblock as possible.)

As a result of this patch, long-term memory fragmentation should be
reduced.

In testing based on 4.9 kernel with stress-highalloc from mmtests
configured for order-4 GFP_KERNEL allocations, this patch has reduced
the number of unmovable allocations falling back to movable pageblocks
by 20%.  The number

Link: http://lkml.kernel.org/r/20170307131545.28577-9-vbabka@suse.cz


Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The migrate scanner in async compaction is currently limited to
MIGRATE_MOVABLE pageblocks.  This is a heuristic intended to reduce
latency, based on the assumption that non-MOVABLE pageblocks are
unlikely to contain movable pages.

However, with the exception of THP's, most high-order allocations are
not movable.  Should the async compaction succeed, this increases the
chance that the non-MOVABLE allocations will fallback to a MOVABLE
pageblock, making the long-term fragmentation worse.

This patch attempts to help the situation by changing async direct
compaction so that the migrate scanner only scans the pageblocks of the
requested migratetype.  If it's a non-MOVABLE type and there are such
pageblocks that do contain movable pages, chances are that the
allocation can succeed within one of such pageblocks, removing the need
for a fallback.  If that fails, the subsequent sync attempt will ignore
this restriction.

In testing based on 4.9 kernel with stress-highalloc from mmtests
configured for order-4 GFP_KERNEL allocations, this patch has reduced
the number of unmovable allocations falling back to movable pageblocks
by 30%.  The number of movable allocations falling back is reduced by
12%.

Link: http://lkml.kernel.org/r/20170307131545.28577-8-vbabka@suse.cz


Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Preparation patch.  We are going to need migratetype at lower layers
than compact_zone() and compact_finished().

Link: http://lkml.kernel.org/r/20170307131545.28577-7-vbabka@suse.cz


Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Preparation for making the decisions more complex and depending on
compact_control flags.  No functional change.

Link: http://lkml.kernel.org/r/20170307131545.28577-6-vbabka@suse.cz


Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When stealing pages from pageblock of a different migratetype, we count
how many free pages were stolen, and change the pageblock's migratetype
if more than half of the pageblock was free.  This might be too
conservative, as there might be other pages that are not free, but were
allocated with the same migratetype as our allocation requested.

While we cannot determine the migratetype of allocated pages precisely
(at least without the page_owner functionality enabled), we can count
pages that compaction would try to isolate for migration - those are
either on LRU or __PageMovable().  The rest can be assumed to be
MIGRATE_RECLAIMABLE or MIGRATE_UNMOVABLE, which we cannot easily
distinguish.  This counting can be done as part of free page stealing
with little additional overhead.

The page stealing code is changed so that it considers free pages plus
pages of the "good" migratetype for the decision whether to change
pageblock's migratetype.

The result should be more accurate migratetype of pageblocks wrt the
actual pages in the pageblocks, when stealing from semi-occupied
pageblocks.  This should help the efficiency of page grouping by
mobility.

In testing based on 4.9 kernel with stress-highalloc from mmtests
configured for order-4 GFP_KERNEL allocations, this patch has reduced
the number of unmovable allocations falling back to movable pageblocks
by 47%.  The number of movable allocations falling back to other
pageblocks are increased by 55%, but these events don't cause permanent
fragmentation, so the tradeoff should be positive.  Later patches also
offset the movable fallback increase to some extent.

[akpm@linux-foundation.org: merge fix]
Link: http://lkml.kernel.org/r/20170307131545.28577-5-vbabka@suse.cz


Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The __rmqueue_fallback() function is called when there's no free page of
requested migratetype, and we need to steal from a different one.

There are various heuristics to make this event infrequent and reduce
permanent fragmentation.  The main one is to try stealing from a
pageblock that has the most free pages, and possibly steal them all at
once and convert the whole pageblock.  Precise searching for such
pageblock would be expensive, so instead the heuristics walks the free
lists from MAX_ORDER down to requested order and assumes that the block
with highest-order free page is likely to also have the most free pages
in total.

Chances are that together with the highest-order page, we steal also
pages of lower orders from the same block.  But then we still split the
highest order page.  This is wasteful and can contribute to
fragmentation instead of avoiding it.

This patch thus changes __rmqueue_fallback() to just steal the page(s)
and put them on the freelist of the requested migratetype, and only
report whether it was successful.  Then we pick (and eventually split)
the smallest page with __rmqueue_smallest().  This all happens under
zone lock, so nobody can steal it from us in the process.  This should
reduce fragmentation due to fallbacks.  At worst we are only stealing a
single highest-order page and waste some cycles by moving it between
lists and then removing it, but fallback is not exactly hot path so that
should not be a concern.  As a side benefit the patch removes some
duplicate code by reusing __rmqueue_smallest().

[vbabka@suse.cz: fix endless loop in the modified __rmqueue()]
  Link: http://lkml.kernel.org/r/59d71b35-d556-4fc9-ee2e-1574259282fd@suse.cz
Link: http://lkml.kernel.org/r/20170307131545.28577-4-vbabka@suse.cz


Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When detecting whether compaction has succeeded in forming a high-order
page, __compact_finished() employs a watermark check, followed by an own
search for a suitable page in the freelists.  This is not ideal for two
reasons:

 - The watermark check also searches high-order freelists, but has a
   less strict criteria wrt fallback. It's therefore redundant and waste
   of cycles. This was different in the past when high-order watermark
   check attempted to apply reserves to high-order pages.

 - The watermark check might actually fail due to lack of order-0 pages.
   Compaction can't help with that, so there's no point in continuing
   because of that. It's possible that high-order page still exists and
   it terminates.

This patch therefore removes the watermark check.  This should save some
cycles and terminate compaction sooner in some cases.

Link: http://lkml.kernel.org/r/20170307131545.28577-3-vbabka@suse.cz


Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Patch series "try to reduce fragmenting fallbacks", v3.

Last year, Johannes Weiner has reported a regression in page mobility
grouping [1] and while the exact cause was not found, I've come up with
some ways to improve it by reducing the number of allocations falling
back to different migratetype and causing permanent fragmentation.

The series was tested with mmtests stress-highalloc modified to do
GFP_KERNEL order-4 allocations, on 4.9 with "mm, vmscan: fix zone
balance check in prepare_kswapd_sleep" (without that, kcompactd indeed
wasn't woken up) on UMA machine with 4GB memory.  There were 5 repeats
of each run, as the extfrag stats are quite volatile (note the stats
below are sums, not averages, as it was less perl hacking for me).

Success rate are the same, already high due to the low allocation order
used, so I'm not including them.

Compaction stats:
(the patches are stacked, and I haven't measured the non-functional-changes
patches separately)

                                     patch 1     patch 2     patch 3     patch 4     patch 7     patch 8
  Compaction stalls                    22449       24680       24846       19765       22059       17480
  Compaction success                   12971       14836       14608       10475       11632        8757
  Compaction failures                   9477        9843       10238        9290       10426        8722
  Page migrate success               3109022     3370438     3312164     1695105     1608435     2111379
  Page migrate failure                911588     1149065     1028264     1112675     1077251     1026367
  Compaction pages isolated          7242983     8015530     7782467     4629063     4402787     5377665
  Compaction migrate scanned       980838938   987367943   957690188   917647238   947155598  1018922197
  Compaction free scanned          557926893   598946443   602236894   594024490   541169699   763651731
  Compaction cost                      10243       10578       10304        8286        8398        9440

Compaction stats are mostly within noise until patch 4, which decreases
the number of compactions, and migrations.  Part of that could be due to
more pageblocks marked as unmovable, and async compaction skipping
those.  This changes a bit with patch 7, but not so much.  Patch 8
increases free scanner stats and migrations, which comes from the
changed termination criteria.  Interestingly number of compactions
decreases - probably the fully compacted pageblock satisfies multiple
subsequent allocations, so it amortizes.

Next comes the extfrag tracepoint, where "fragmenting" means that an
allocation had to fallback to a pageblock of another migratetype which
wasn't fully free (which is almost all of the fallbacks).  I have
locally added another tracepoint for "Page steal" into
steal_suitable_fallback() which triggers in situations where we are
allowed to do move_freepages_block().  If we decide to also do
set_pageblock_migratetype(), it's "Pages steal with pageblock" with
break down for which allocation migratetype we are stealing and from
which fallback migratetype.  The last part "due to counting" comes from
patch 4 and counts the events where the counting of movable pages
allowed us to change pageblock's migratetype, while the number of free
pages alone wouldn't be enough to cross the threshold.

                                                       patch 1     patch 2     patch 3     patch 4     patch 7     patch 8
  Page alloc extfrag event                            10155066     8522968    10164959    15622080    13727068    13140319
  Extfrag fragmenting                                 10149231     8517025    10159040    15616925    13721391    13134792
  Extfrag fragmenting for unmovable                     159504      168500      184177       97835       70625       56948
  Extfrag fragmenting unmovable placed with movable     153613      163549      172693       91740       64099       50917
  Extfrag fragmenting unmovable placed with reclaim.      5891        4951       11484        6095        6526        6031
  Extfrag fragmenting for reclaimable                     4738        4829        6345        4822        5640        5378
  Extfrag fragmenting reclaimable placed with movable     1836        1902        1851        1579        1739        1760
  Extfrag fragmenting reclaimable placed with unmov.      2902        2927        4494        3243        3901        3618
  Extfrag fragmenting for movable                      9984989     8343696     9968518    15514268    13645126    13072466
  Pages steal                                           179954      192291      210880      123254       94545       81486
  Pages steal with pageblock                             22153       18943       20154       33562       29969       33444
  Pages steal with pageblock for unmovable               14350       12858       13256       20660       19003       20852
  Pages steal with pageblock for unmovable from mov.     12812       11402       11683       19072       17467       19298
  Pages steal with pageblock for unmovable from recl.     1538        1456        1573        1588        1536        1554
  Pages steal with pageblock for movable                  7114        5489        5965       11787       10012       11493
  Pages steal with pageblock for movable from unmov.      6885        5291        5541       11179        9525       10885
  Pages steal with pageblock for movable from recl.        229         198         424         608         487         608
  Pages steal with pageblock for reclaimable               689         596         933        1115         954        1099
  Pages steal with pageblock for reclaimable from unmov.   273         219         537         658         547         667
  Pages steal with pageblock for reclaimable from mov.     416         377         396         457         407         432
  Pages steal with pageblock due to counting                                                 11834       10075        7530
  ... for unmovable                                                                           8993        7381        4616
  ... for movable                                                                             2792        2653        2851
  ... for reclaimable                                                                           49          41          63

What we can see is that "Extfrag fragmenting for unmovable" and "...
placed with movable" drops with almost each patch, which is good as we
are polluting less movable pageblocks with unmovable pages.

The most significant change is patch 4 with movable page counting.  On
the other hand it increases "Extfrag fragmenting for movable" by 50%.
"Pages steal" drops though, so these movable allocation fallbacks find
only small free pages and are not allowed to steal whole pageblocks
back.  "Pages steal with pageblock" raises, because the patch increases
the chances of pageblock migratetype changes to happen.  This affects
all migratetypes.

The summary is that patch 4 is not a clear win wrt these stats, but I
believe that the tradeoff it makes is a good one.  There's less
pollution of movable pageblocks by unmovable allocations.  There's less
stealing between pageblock, and those that remain have higher chance of
changing migratetype also the pageblock itself, so it should more
faithfully reflect the migratetype of the pages within the pageblock.
The increase of movable allocations falling back to unmovable pageblock
might look dramatic, but those allocations can be migrated by compaction
when needed, and other patches in the series (7-9) improve that aspect.

Patches 7 and 8 continue the trend of reduced unmovable fallbacks and
also reduce the impact on movable fallbacks from patch 4.

[1] https://www.spinics.net/lists/linux-mm/msg114237.html

This patch (of 8):

While currently there are (mostly by accident) no holes in struct
compact_control (on x86_64), but we are going to add more bool flags, so
place them all together to the end of the structure.  While at it, just
order all fields from largest to smallest.

Link: http://lkml.kernel.org/r/20170307131545.28577-2-vbabka@suse.cz


Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit 37d69ee3

 ("docs: bump minimal GNU Make version to 3.81")
changes one entry of GNU make version in the changes.rst, there's still
one more entry saying that one need version 3.80.  Fix that.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull cifs fixes from Steve French:
 "Various fixes for stable for CIFS/SMB3 especially for better
  interoperability for SMB3 to Macs.

  It also includes Pavel's improvements to SMB3 async i/o support
  (which is much faster now)"

* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
  CIFS: add misssing SFM mapping for doublequote
  SMB3: Work around mount failure when using SMB3 dialect to Macs
  cifs: fix CIFS_IOC_GET_MNT_INFO oops
  CIFS: fix mapping of SFM_SPACE and SFM_PERIOD
  CIFS: fix oplock break deadlocks
  cifs: fix CIFS_ENUMERATE_SNAPSHOTS oops
  cifs: fix leak in FSCTL_ENUM_SNAPS response handling
  Set unicode flag on cifs echo request to avoid Mac error
  CIFS: Add asynchronous write support through kernel AIO
  CIFS: Add asynchronous read support through kernel AIO
  CIFS: Add asynchronous context to support kernel AIO
  cifs: fix IPv6 link local, with scope id, address parsing
  cifs: small underflow in cnvrtDosUnixTm()

Pull xfs updates from Darrick Wong:
 "Here are the XFS changes for 4.12. The big new feature for this
  release is the new space mapping ioctl that we've been discussing
  since LSF2016, but other than that most of the patches are larger bug
  fixes, memory corruption prevention, and other cleanups.

  Summary:
   - various code cleanups
   - introduce GETFSMAP ioctl
   - various refactoring
   - avoid dio reads past eof
   - fix memory corruption and other errors with fragmented directory blocks
   - fix accidental userspace memory corruptions
   - publish fs uuid in superblock
   - make fstrim terminatable
   - fix race between quotaoff and in-core inode creation
   - avoid use-after-free when finishing up w/ buffer heads
   - reserve enough space to handle bmap tree resizing during cow remap"

* tag 'xfs-4.12-merge-7' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (53 commits)
  xfs: fix use-after-free in xfs_finish_page_writeback
  xfs: reserve enough blocks to handle btree splits when remapping
  xfs: wait on new inodes during quotaoff dquot release
  xfs: update ag iterator to support wait on new inodes
  xfs: support ability to wait on new inodes
  xfs: publish UUID in struct super_block
  xfs: Allow user to kill fstrim process
  xfs: better log intent item refcount checking
  xfs: fix up quotacheck buffer list error handling
  xfs: remove xfs_trans_ail_delete_bulk
  xfs: don't use bool values in trace buffers
  xfs: fix getfsmap userspace memory corruption while setting OF_LAST
  xfs: fix __user annotations for xfs_ioc_getfsmap
  xfs: corruption needs to respect endianess too!
  xfs: use NULL instead of 0 to initialize a pointer in xfs_ioc_getfsmap
  xfs: use NULL instead of 0 to initialize a pointer in xfs_getfsmap
  xfs: simplify validation of the unwritten extent bit
  xfs: remove unused values from xfs_exntst_t
  xfs: remove the unused XFS_MAXLINK_1 define
  xfs: more do_div cleanups
  ...

Pull block fixes and updates from Jens Axboe:
 "Some fixes and followup features/changes that should go in, in this
  merge window. This contains:

   - Two fixes for lightnvm from Javier, fixing problems in the new code
     merge previously in this merge window.

   - A fix from Jan for the backing device changes, fixing an issue in
     NFS that causes a failure to mount on certain setups.

   - A change from Christoph, cleaning up the blk-mq init and exit
     request paths.

   - Remove elevator_change(), which is now unused. From Bart.

   - A fix for queue operation invocation on a dead queue, from Bart.

   - A series fixing up mtip32xx for blk-mq scheduling, removing a
     bandaid we previously had in place for this. From me.

   - A regression fix for this series, fixing a case where we wait on
     workqueue flushing from an invalid (non-blocking) context. From me.

   - A fix/optimization from Ming, ensuring that we don't both quiesce
     and freeze a queue at the same time.

   - A fix from Peter on lock ordering for CPU hotplug. Not a real
     problem right now, but will be once the CPU hotplug rework goes in.

   - A series from Omar, cleaning up out blk-mq debugfs support, and
     adding support for exporting info from schedulers in debugfs as
     well. This is really useful in debugging stalls or livelocks. From
     Omar"

* 'for-linus' of git://git.kernel.dk/linux-block: (28 commits)
  mq-deadline: add debugfs attributes
  kyber: add debugfs attributes
  blk-mq-debugfs: allow schedulers to register debugfs attributes
  blk-mq: untangle debugfs and sysfs
  blk-mq: move debugfs declarations to a separate header file
  blk-mq: Do not invoke queue operations on a dead queue
  blk-mq-debugfs: get rid of a bunch of boilerplate
  blk-mq-debugfs: rename hw queue directories from <n> to hctx<n>
  blk-mq-debugfs: don't open code strstrip()
  blk-mq-debugfs: error on long write to queue "state" file
  blk-mq-debugfs: clean up flag definitions
  blk-mq-debugfs: separate flags with |
  nfs: Fix bdi handling for cloned superblocks
  block/mq: Cure cpu hotplug lock inversion
  lightnvm: fix bad back free on error path
  lightnvm: create cmd before allocating request
  blk-mq: don't use sync workqueue flushing from drivers
  mtip32xx: convert internal commands to regular block infrastructure
  mtip32xx: cleanup internal tag assumptions
  block: don't call blk_mq_quiesce_queue() after queue is frozen
  ...

Now that kref is using the refcount apis, the _GPL markings are getting
exported to places that it previously wasn't.  Now kref.h is GPLv2
licensed, so any non-GPL code using it better be talking to some
lawyers, but changing api markings isn't considered "nice", so let's fix
this up.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Since 2014, you can't successfully build kernels with GNU Make version
3.80. Example errors:

  $ git describe
  v4.11
  $ make --version | head -1
  GNU Make 3.80
  $ make defconfig
    HOSTCC  scripts/basic/fixdep
  scripts/Makefile.host:135: *** missing separator.  Stop.
  make: *** [defconfig] Error 2
  $ make ARCH=arm64 help
  arch/arm64/Makefile:43: *** unterminated call to function `warning': missing `)'.  Stop.
  $ make help >/dev/null
  ./Documentation/Makefile.sphinx:25: Extraneous text after `else' directive
  ./Documentation/Makefile.sphinx:31: *** only one `else' per conditional.  Stop.
  make: *** [help] Error 2

The first breakage was introduced by commit c8589d1e

 ("kbuild:
handle multi-objs dependency appropriately").  Since then (i.e. v3.18),
GNU Make 3.80 has not been able to compile the kernel, but nobody has
ever complained aboutt (or noticed) it.

Even GNU Make 3.81 is more than 10 years old.  It would not hurt to
match the documentation with reality instead of fixing makefiles.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit 17a9be31

 ("initramfs: Always do fput() and load modules after
rootfs populate") introduced an error for the

    CONFIG_BLK_DEV_RAM=y

case, because even though the code looks fine, the compiler really wants
a statement after a label, or you'll get complaints:

  init/initramfs.c: In function 'populate_rootfs':
  init/initramfs.c:644:2: error: label at end of compound statement

That commit moved the subsequent statements to outside the compound
statement, leaving the label without any associated statements.

Reported-by: Jörg Otte <jrg.otte@gmail.com>
Fixes: 17a9be31 ("initramfs: Always do fput() and load modules after rootfs populate")
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: stable@vger.kernel.org  # if 17a9be31

 gets backported
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull DeviceTree updates from Rob Herring:

 - fix sparse warnings in drivers/of/

 - add more overlay unittests

 - update dtc to v1.4.4-8-g756ffc4f52f6. This adds more checks on dts
   files such as unit-address formatting and stricter character sets for
   node and property names

 - add a common DT modalias function

 - move trivial-devices.txt up and out of i2c dir

 - ARM NVIC interrupt controller binding

 - vendor prefixes for Sensirion, Dioo, Nordic, ROHM

 - correct some binding file locations

* tag 'devicetree-for-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (24 commits)
  of: fix sparse warnings in fdt, irq, reserved mem, and resolver code
  of: fix sparse warning in of_pci_range_parser_one
  of: fix sparse warnings in of_find_next_cache_node
  of/unittest: Missing unlocks on error
  of: fix uninitialized variable warning for overlay test
  of: fix unittest build without CONFIG_OF_OVERLAY
  of: Add unit tests for applying overlays
  of: per-file dtc compiler flags
  fpga: region: add missing DT documentation for config complete timeout
  of: Add vendor prefix for ROHM Semiconductor
  of: fix "/cpus" reference leak in of_numa_parse_cpu_nodes()
  of: Add vendor prefix for Nordic Semiconductor
  dt-bindings: arm,nvic: Binding for ARM NVIC interrupt controller on Cortex-M
  dtc: update warning settings for new bus and node/property name checks
  scripts/dtc: Update to upstream version v1.4.4-8-g756ffc4f52f6
  scripts/dtc: automate getting dtc version and log in update script
  of: Add function for generating a DT modalias with a newline
  of: fix of_device_get_modalias returned length when truncating buffers
  Documentation: devicetree: move trivial-devices out of I2C realm
  dt-bindings: add vendor prefix for Dioo
  ..

Merge tag 'for-4.12/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper fixes from Mike Snitzer:

 - DM cache metadata fixes to short-circuit operations that require the
   metadata not be in 'fail_io' mode. Otherwise crashes are possible.

 - a DM cache fix to address the inability to adapt to continuous IO
   that happened to also reflect a changing working set (which required
   old blocks be demoted before the new working set could be promoted)

 - a DM cache smq policy cleanup that fell out from reviewing the above

 - fix the Kconfig help text for CONFIG_DM_INTEGRITY

* tag 'for-4.12/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm cache metadata: fail operations if fail_io mode has been established
  dm integrity: improve the Kconfig help text for DM_INTEGRITY
  dm cache policy smq: cleanup free_target_met() and clean_target_met()
  dm cache policy smq: allow demotions to happen even during continuous IO

Pull libnvdimm updates from Dan Williams:
 "The bulk of this has been in multiple -next releases. There were a few
  late breaking fixes and small features that got added in the last
  couple days, but the whole set has received a build success
  notification from the kbuild robot.

  Change summary:

   - Region media error reporting: A libnvdimm region device is the
     parent to one or more namespaces. To date, media errors have been
     reported via the "badblocks" attribute attached to pmem block
     devices for namespaces in "raw" or "memory" mode. Given that
     namespaces can be in "device-dax" or "btt-sector" mode this new
     interface reports media errors generically, i.e. independent of
     namespace modes or state.

     This subsequently allows userspace tooling to craft "ACPI 6.1
     Section 9.20.7.6 Function Index 4 - Clear Uncorrectable Error"
     requests and submit them via the ioctl path for NVDIMM root bus
     devices.

   - Introduce 'struct dax_device' and 'struct dax_operations': Prompted
     by a request from Linus and feedback from Christoph this allows for
     dax capable drivers to publish their own custom dax operations.
     This fixes the broken assumption that all dax operations are
     related to a persistent memory device, and makes it easier for
     other architectures and platforms to add customized persistent
     memory support.

   - 'libnvdimm' core updates: A new "deep_flush" sysfs attribute is
     available for storage appliance applications to manually trigger
     memory controllers to drain write-pending buffers that would
     otherwise be flushed automatically by the platform ADR
     (asynchronous-DRAM-refresh) mechanism at a power loss event.
     Support for "locked" DIMMs is included to prevent namespaces from
     surfacing when the namespace label data area is locked. Finally,
     fixes for various reported deadlocks and crashes, also tagged for
     -stable.

   - ACPI / nfit driver updates: General updates of the nfit driver to
     add DSM command overrides, ACPI 6.1 health state flags support, DSM
     payload debug available by default, and various fixes.

  Acknowledgements that came after the branch was pushed:

   - commmit 565851c9

 "device-dax: fix sysfs attribute deadlock":
Tested-by: Yi Zhang <yizhan@redhat.com>

   - commit 23f49844

 "libnvdimm: rework region badblocks clearing"
Tested-by: Toshi Kani <toshi.kani@hpe.com&gt;">

* tag 'libnvdimm-for-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (52 commits)
  libnvdimm, pfn: fix 'npfns' vs section alignment
  libnvdimm: handle locked label storage areas
  libnvdimm: convert NDD_ flags to use bitops, introduce NDD_LOCKED
  brd: fix uninitialized use of brd->dax_dev
  block, dax: use correct format string in bdev_dax_supported
  device-dax: fix sysfs attribute deadlock
  libnvdimm: restore "libnvdimm: band aid btt vs clear poison locking"
  libnvdimm: fix nvdimm_bus_lock() vs device_lock() ordering
  libnvdimm: rework region badblocks clearing
  acpi, nfit: kill ACPI_NFIT_DEBUG
  libnvdimm: fix clear length of nvdimm_forget_poison()
  libnvdimm, pmem: fix a NULL pointer BUG in nd_pmem_notify
  libnvdimm, region: sysfs trigger for nvdimm_flush()
  libnvdimm: fix phys_addr for nvdimm_clear_poison
  x86, dax, pmem: remove indirection around memcpy_from_pmem()
  block: remove block_device_operations ->direct_access()
  block, dax: convert bdev_dax_supported() to dax_direct_access()
  filesystem-dax: convert to dax_direct_access()
  Revert "block: use DAX for partition table reads"
  ext2, ext4, xfs: retrieve dax_device for iomap operations
  ...

Pull staging/IIO updates from Greg KH:
 "Here is the big staging tree update for 4.12-rc1.

  It's a big one, adding about 350k new lines of crap^Wcode, mostly all
  in a big dump of media drivers from Intel. But there's other new
  drivers in here as well, yet-another-wifi driver, new IIO drivers, and
  a new crypto accelerator.

  We also deleted a bunch of stuff, mostly in patch cleanups, but also
  the Android ION code has shrunk a lot, and the Android low memory
  killer driver was finally deleted, much to the celebration of the -mm
  developers.

  All of these have been in linux-next with a few build issues that will
  show up when you merge to your tree"

Merge conflicts in the new rtl8723bs driver (due to the wifi changes
this merge window) handled as per linux-next, courtesy of Stephen
Rothwell.

* tag 'staging-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (1182 commits)
  staging: fsl-mc/dpio: add cpu <--> LE conversion for dpaa2_fd
  staging: ks7010: remove line continuations in quoted strings
  staging: vt6656: use tabs instead of spaces
  staging: android: ion: Fix unnecessary initialization of static variable
  staging: media: atomisp: fix range checking on clk_num
  staging: media: atomisp: fix misspelled word in comment
  staging: media: atomisp: kmap() can't fail
  staging: atomisp: remove #ifdef for runtime PM functions
  staging: atomisp: satm include directory is gone
  atomisp: remove some more unused files
  atomisp: remove hmm_load/store/clear indirections
  atomisp: kill off mmgr_free
  atomisp: clean up the hmm init/cleanup indirections
  atomisp: handle allocation calls before init in the hmm layer
  staging: fsl-dpaa2/eth: Add maintainer for Ethernet driver
  staging: fsl-dpaa2/eth: Add TODO file
  staging: fsl-dpaa2/eth: Add trace points
  staging: fsl-dpaa2/eth: Add driver specific stats
  staging: fsl-dpaa2/eth: Add ethtool support
  staging: fsl-dpaa2/eth: Add Freescale DPAA2 Ethernet driver
  ...

Pull media updates from Mauro Carvalho Chehab:
 "Media updates for v4.12-rc1:

   - new driver to support mediatek jpeg in hardware codec

   - rc-lirc, s5p-cec and st-cec staging drivers got promoted

   - hardware histogram support for vsp1 driver

   - added Virtual Media Controller driver, to make easier to test the
     media controller

   - added a new CEC driver (rainshadow-cec)

   - removed two staging LIRC drivers for obscure hardware that are too
     obsolete

   - added support for Intel SR300 Depth camera

   - some improvements at CEC and RC core

   - lots of driver cleanups, improvements all over the tree

  With this series, we're finally getting rid of the LIRC staging
  driver. There's just one left (lirc_zilog), with require more care,
  as part of its functionality (IR RX) is already provided by another
  driver. Work in progress to convert it on the proper way"

* tag 'media/v4.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (304 commits)
  [media] ov2640: print error if devm_*_optional*() fails
  [media] atmel-isc: Fix the static checker warning
  [media] ov2640: add support for MEDIA_BUS_FMT_YVYU8_2X8 and MEDIA_BUS_FMT_VYUY8_2X8
  [media] ov2640: fix vflip control
  [media] ov2640: fix duplicate width+height returning from ov2640_select_win()
  [media] ov2640: add missing write to size change preamble
  [media] ov2640: add information about DSP register 0xc7
  [media] ov2640: improve banding filter register definitions/documentation
  [media] ov2640: fix init sequence alignment
  [media] ov2640: make GPIOLIB an optional dependency
  [media] xc5000: fix spelling mistake: "calibration"
  [media] vidioc-queryctrl.rst: fix menu/int menu references
  [media] media-entity: only call dev_dbg_obj if mdev is not NULL
  [media] pixfmt-meta-vsp1-hgo.rst: remove spurious '-'
  [media] mtk-vcodec: avoid warnings because of empty macros
  [media] coda: bump maximum number of internal framebuffers to 17
  [media] media: mtk-vcodec: remove informative log
  [media] subdev-formats.rst: remove spurious '-'
  [media] dw2102: limit messages to buffer size
  [media] ttusb2: limit messages to buffer size
  ...

Pull drm CoC pointer from Dave Airlie:
 "Small supplementary pull request. I didn't want anyone saying we snuck
  this in in a the middle of a big pile of changes, so here is a clearly
  separate pull request documenting the code of conduct introduced for
  freedesktop.org and how it relates to dri-devel community"

* tag 'drm-coc-for-v4.12-rc1' of git://people.freedesktop.org/~airlied/linux:
  drm: Document code of conduct

Pull drm tegra updates from Dave Airlie:
 "I missed a pull request from Thierry, this stuff has been in
  linux-next for a while anyways.

  It does contain a branch from the iommu tree, but Thierry said it
  should be fine"

* tag 'drm-forgot-about-tegra-for-v4.12-rc1' of git://people.freedesktop.org/~airlied/linux:
  gpu: host1x: Fix host1x driver shutdown
  gpu: host1x: Support module reset
  gpu: host1x: Sort includes alphabetically
  drm/tegra: Add VIC support
  dt-bindings: Add bindings for the Tegra VIC
  drm/tegra: Add falcon helper library
  drm/tegra: Add Tegra DRM allocation API
  drm/tegra: Add tiling FB modifiers
  drm/tegra: Don't leak kernel pointer to userspace
  drm/tegra: Protect IOMMU operations by mutex
  drm/tegra: Enable IOVA API when IOMMU support is enabled
  gpu: host1x: Add IOMMU support
  gpu: host1x: Fix potential out-of-bounds access
  iommu/iova: Fix compile error with CONFIG_IOMMU_IOVA=m
  iommu: Add dummy implementations for !IOMMU_IOVA
  MAINTAINERS: Add related headers to IOMMU section
  iommu/iova: Consolidate code for adding new node to iovad domain rbtree

Pull GFS2 updates from Bob Peterson:
 "We've got ten GFS2 patches for this merge window.

   - Andreas Gruenbacher wrote a patch to replace the deprecated call to
     rhashtable_walk_init with rhashtable_walk_enter.

   - Andreas also wrote a patch to eliminate redundant code in two of
     our debugfs sequence files.

   - Andreas also cleaned up the rhashtable key ugliness Linus pointed
     out during this cycle, following Linus's suggestions.

   - Andreas also wrote a patch to take advantage of his new function
     rhashtable_lookup_get_insert_fast. This makes glock lookup faster
     and more bullet-proof.

   - Andreas also wrote a patch to revert a patch in the evict path that
     caused occasional deadlocks, and is no longer needed.

   - Andrew Price wrote a patch to re-enable fallocate for the rindex
     system file to enable gfs2_grow to grow properly on secondary file
     system grow operations.

   - I wrote a patch to initialize an inode number field to make certain
     kernel trace points more understandable.

   - I also wrote a patch that makes GFS2 file system "withdraw" work
     more like it should by ignoring operations after a withdraw that
     would formerly cause a BUG() and kernel panic.

   - I also reworked the entire truncate/delete algorithm, scrapping the
     old recursive algorithm in favor of a new non-recursive algorithm.
     This was done for performance: This way, GFS2 no longer needs to
     lock multiple resource groups while doing truncates and deletes of
     files that cross multiple resource group boundaries, allowing for
     better parallelism. It also solves a problem whereby deleting large
     files would request a large chunk of kernel memory, which resulted
     in a get_page_from_freelist warning.

   - Due to a regression found during testing, I added a new patch to
     correct 'GFS2: Prevent BUG from occurring when normal Withdraws
     occur'."

* tag 'gfs2-4.12.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  GFS2: Allow glocks to be unlocked after withdraw
  GFS2: Non-recursive delete
  gfs2: Re-enable fallocate for the rindex
  Revert "GFS2: Wait for iopen glock dequeues"
  gfs2: Switch to rhashtable_lookup_get_insert_fast
  GFS2: Temporarily zero i_no_addr when creating a dinode
  gfs2: Don't pack struct lm_lockname
  gfs2: Deduplicate gfs2_{glocks,glstats}_open
  gfs2: Replace rhashtable_walk_init with rhashtable_walk_enter
  GFS2: Prevent BUG from occurring when normal Withdraws occur

Pull orangefs updates from Mike Marshall:
 "Orangefs cleanups, fixes and statx support.

  Some cleanups:

   - remove unused get_fsid_from_ino
   - fix bounds check for listxattr
   - clean up oversize xattr validation
   - do not set getattr_time on orangefs_lookup
   - return from orangefs_devreq_read quickly if possible
   - do not wait for timeout if umounting
   - handle zero size write in debugfs

  Bug fixes:

   - do not check possibly stale size on truncate
   - ensure the userspace component is unmounted if mount fails
   - total reimplementation of dir.c

  New feature:

   - implement statx

  The new implementation of dir.c is kind of a big deal, all new code.
  It has been posted to fs-devel during the previous rc period, we
  didn't get much review or feedback from there, but it has been
  reviewed very heavily here, so much so that we have two entire
  versions of the reimplementation.

  Not only does the new implementation fix some xfstests, but it passes
  all the new tests we made here that involve seeking and rewinding and
  giant directories and long file names. The new dir code has three
  patches itself:

   - skip forward to the next directory entry if seek is short
   - invalidate stored directory on seek
   - count directory pieces correctly"

* tag 'for-linus-4.12-ofs-1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux:
  orangefs: count directory pieces correctly
  orangefs: invalidate stored directory on seek
  orangefs: skip forward to the next directory entry if seek is short
  orangefs: handle zero size write in debugfs
  orangefs: do not wait for timeout if umounting
  orangefs: return from orangefs_devreq_read quickly if possible
  orangefs: ensure the userspace component is unmounted if mount fails
  orangefs: do not check possibly stale size on truncate
  orangefs: implement statx
  orangefs: remove ORANGEFS_READDIR macros
  orangefs: support very large directories
  orangefs: support llseek on directories
  orangefs: rewrite readdir to fix several bugs
  orangefs: do not set getattr_time on orangefs_lookup
  orangefs: clean up oversize xattr validation
  orangefs: fix bounds check for listxattr
  orangefs: remove unused get_fsid_from_ino

Pull befs fix from Luis de Bethencourt:
 "One fix from Fabian Frederick making the nfs client still work after a
  cache drop"

* tag 'befs-v4.12-rc1' of git://github.com/luisbg/linux-befs:
  befs: make export work with cold dcache

Pull initramfs fix from Stafford Horne:
 "This is a fix for an issue that has caused 4.11 to not boot on
  OpenRISC. I should have caught this during the 4.11 cycle but I had
  been busy on testing some other series of patches.

  I would have considered pushing it though a different path but Al Viro
  suggested submitting directly to you.

  Also, its just one as I havent really got anything else ready on my
  queue for 4.12.

  Summary:

   - Ensure fput() flush is done even for builtin initramfs"

* tag 'initramfs-fix-4.12-rc1' of git://github.com/stffrdhrn/linux:
  initramfs: Always do fput() and load modules after rootfs populate

This bug fixes a regression introduced by patch 0d1c7ae9

.

The intent of the patch was to stop promoting glocks after a
file system is withdrawn due to a variety of errors, because doing
so results in a BUG(). (You should be able to unmount after a
withdraw rather than having the kernel panic.)

Unfortunately, it also stopped demotions, so glocks could not be
unlocked after withdraw, which means the unmount would hang.

This patch allows function do_xmote to demote locks to an
unlocked state after a withdraw, but not promote them.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>

Commit 28b783e4

 ("xfs: bufferhead chains are invalid after
end_page_writeback") fixed one use-after-free issue by
pre-calculating the loop conditionals before calling bh->b_end_io()
in the end_io processing loop, but it assigned 'next' pointer before
checking end offset boundary & breaking the loop, at which point the
bh might be freed already, and caused use-after-free.

This is caught by KASAN when running fstests generic/127 on sub-page
block size XFS.

[ 2517.244502] run fstests generic/127 at 2017-04-27 07:30:50
[ 2747.868840] ==================================================================
[ 2747.876949] BUG: KASAN: use-after-free in xfs_destroy_ioend+0x3d3/0x4e0 [xfs] at addr ffff8801395ae698
...
[ 2747.918245] Call Trace:
[ 2747.920975]  dump_stack+0x63/0x84
[ 2747.924673]  kasan_object_err+0x21/0x70
[ 2747.928950]  kasan_report+0x271/0x530
[ 2747.933064]  ? xfs_destroy_ioend+0x3d3/0x4e0 [xfs]
[ 2747.938409]  ? end_page_writeback+0xce/0x110
[ 2747.943171]  __asan_report_load8_noabort+0x19/0x20
[ 2747.948545]  xfs_destroy_ioend+0x3d3/0x4e0 [xfs]
[ 2747.953724]  xfs_end_io+0x1af/0x2b0 [xfs]
[ 2747.958197]  process_one_work+0x5ff/0x1000
[ 2747.962766]  worker_thread+0xe4/0x10e0
[ 2747.966946]  kthread+0x2d3/0x3d0
[ 2747.970546]  ? process_one_work+0x1000/0x1000
[ 2747.975405]  ? kthread_create_on_node+0xc0/0xc0
[ 2747.980457]  ? syscall_return_slowpath+0xe6/0x140
[ 2747.985706]  ? do_page_fault+0x30/0x80
[ 2747.989887]  ret_from_fork+0x2c/0x40
[ 2747.993874] Object at ffff8801395ae690, in cache buffer_head size: 104
[ 2748.001155] Allocated:
[ 2748.003782] PID = 8327
[ 2748.006411]  save_stack_trace+0x1b/0x20
[ 2748.010688]  save_stack+0x46/0xd0
[ 2748.014383]  kasan_kmalloc+0xad/0xe0
[ 2748.018370]  kasan_slab_alloc+0x12/0x20
[ 2748.022648]  kmem_cache_alloc+0xb8/0x1b0
[ 2748.027024]  alloc_buffer_head+0x22/0xc0
[ 2748.031399]  alloc_page_buffers+0xd1/0x250
[ 2748.035968]  create_empty_buffers+0x30/0x410
[ 2748.040730]  create_page_buffers+0x120/0x1b0
[ 2748.045493]  __block_write_begin_int+0x17a/0x1800
[ 2748.050740]  iomap_write_begin+0x100/0x2f0
[ 2748.055308]  iomap_zero_range_actor+0x253/0x5c0
[ 2748.060362]  iomap_apply+0x157/0x270
[ 2748.064347]  iomap_zero_range+0x5a/0x80
[ 2748.068624]  iomap_truncate_page+0x6b/0xa0
[ 2748.073227]  xfs_setattr_size+0x1f7/0xa10 [xfs]
[ 2748.078312]  xfs_vn_setattr_size+0x68/0x140 [xfs]
[ 2748.083589]  xfs_file_fallocate+0x4ac/0x820 [xfs]
[ 2748.088838]  vfs_fallocate+0x2cf/0x780
[ 2748.093021]  SyS_fallocate+0x48/0x80
[ 2748.097006]  do_syscall_64+0x18a/0x430
[ 2748.101186]  return_from_SYSCALL_64+0x0/0x6a
[ 2748.105948] Freed:
[ 2748.108189] PID = 8327
[ 2748.110816]  save_stack_trace+0x1b/0x20
[ 2748.115093]  save_stack+0x46/0xd0
[ 2748.118788]  kasan_slab_free+0x73/0xc0
[ 2748.122969]  kmem_cache_free+0x7a/0x200
[ 2748.127247]  free_buffer_head+0x41/0x80
[ 2748.131524]  try_to_free_buffers+0x178/0x250
[ 2748.136316]  xfs_vm_releasepage+0x2e9/0x3d0 [xfs]
[ 2748.141563]  try_to_release_page+0x100/0x180
[ 2748.146325]  invalidate_inode_pages2_range+0x7da/0xcf0
[ 2748.152087]  xfs_shift_file_space+0x37d/0x6e0 [xfs]
[ 2748.157557]  xfs_collapse_file_space+0x49/0x120 [xfs]
[ 2748.163223]  xfs_file_fallocate+0x2a7/0x820 [xfs]
[ 2748.168462]  vfs_fallocate+0x2cf/0x780
[ 2748.172642]  SyS_fallocate+0x48/0x80
[ 2748.176629]  do_syscall_64+0x18a/0x430
[ 2748.180810]  return_from_SYSCALL_64+0x0/0x6a

Fixed it by checking on offset against end & breaking out first,
dereference bh only if there're still bufferheads to process.

Signed-off-by: Eryu Guan <eguan@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

Pull arm64 updates from Catalin Marinas:

 - kdump support, including two necessary memblock additions:
   memblock_clear_nomap() and memblock_cap_memory_range()

 - ARMv8.3 HWCAP bits for JavaScript conversion instructions, complex
   numbers and weaker release consistency

 - arm64 ACPI platform MSI support

 - arm perf updates: ACPI PMU support, L3 cache PMU in some Qualcomm
   SoCs, Cortex-A53 L2 cache events and DTLB refills, MAINTAINERS update
   for DT perf bindings

 - architected timer errata framework (the arch/arm64 changes only)

 - support for DMA_ATTR_FORCE_CONTIGUOUS in the arm64 iommu DMA API

 - arm64 KVM refactoring to use common system register definitions

 - remove support for ASID-tagged VIVT I-cache (no ARMv8 implementation
   using it and deprecated in the architecture) together with some
   I-cache handling clean-up

 - PE/COFF EFI header clean-up/hardening

 - define BUG() instruction without CONFIG_BUG

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (92 commits)
  arm64: Fix the DMA mmap and get_sgtable API with DMA_ATTR_FORCE_CONTIGUOUS
  arm64: Print DT machine model in setup_machine_fdt()
  arm64: pmu: Wire-up Cortex A53 L2 cache events and DTLB refills
  arm64: module: split core and init PLT sections
  arm64: pmuv3: handle pmuv3+
  arm64: Add CNTFRQ_EL0 trap handler
  arm64: Silence spurious kbuild warning on menuconfig
  arm64: pmuv3: use arm_pmu ACPI framework
  arm64: pmuv3: handle !PMUv3 when probing
  drivers/perf: arm_pmu: add ACPI framework
  arm64: add function to get a cpu's MADT GICC table
  drivers/perf: arm_pmu: split out platform device probe logic
  drivers/perf: arm_pmu: move irq request/free into probe
  drivers/perf: arm_pmu: split cpu-local irq request/free
  drivers/perf: arm_pmu: rename irq request/free functions
  drivers/perf: arm_pmu: handle no platform_device
  drivers/perf: arm_pmu: simplify cpu_pmu_request_irqs()
  drivers/perf: arm_pmu: factor out pmu registration
  drivers/perf: arm_pmu: fold init into alloc
  drivers/perf: arm_pmu: define armpmu_init_fn
  ...

Otherwise it is possible to trigger crashes due to the metadata being
inaccessible yet these methods don't safely account for that possibility
without these checks.

Cc: stable@vger.kernel.org
Reported-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Pull powerpc updates from Michael Ellerman:
 "Highlights include:

   - Larger virtual address space on 64-bit server CPUs. By default we
     use a 128TB virtual address space, but a process can request access
     to the full 512TB by passing a hint to mmap().

   - Support for the new Power9 "XIVE" interrupt controller.

   - TLB flushing optimisations for the radix MMU on Power9.

   - Support for CAPI cards on Power9, using the "Coherent Accelerator
     Interface Architecture 2.0".

   - The ability to configure the mmap randomisation limits at build and
     runtime.

   - Several small fixes and cleanups to the kprobes code, as well as
     support for KPROBES_ON_FTRACE.

   - Major improvements to handling of system reset interrupts,
     correctly treating them as NMIs, giving them a dedicated stack and
     using a new hypervisor call to trigger them, all of which should
     aid debugging and robustness.

   - Many fixes and other minor enhancements.

  Thanks to: Alastair D'Silva, Alexey Kardashevskiy, Alistair Popple,
  Andrew Donnellan, Aneesh Kumar K.V, Anshuman Khandual, Anton
  Blanchard, Balbir Singh, Ben Hutchings, Benjamin Herrenschmidt,
  Bhupesh Sharma, Chris Packham, Christian Zigotzky, Christophe Leroy,
  Christophe Lombard, Daniel Axtens, David Gibson, Gautham R. Shenoy,
  Gavin Shan, Geert Uytterhoeven, Guilherme G. Piccoli, Hamish Martin,
  Hari Bathini, Kees Cook, Laurent Dufour, Madhavan Srinivasan, Mahesh J
  Salgaonkar, Mahesh Salgaonkar, Masami Hiramatsu, Matt Brown, Matthew
  R. Ochs, Michael Neuling, Naveen N. Rao, Nicholas Piggin, Oliver
  O'Halloran, Pan Xinhui, Paul Mackerras, Rashmica Gupta, Russell
  Currey, Sukadev Bhattiprolu, Thadeu Lima de Souza Cascardo, Tobin C.
  Harding, Tyrel Datwyler, Uma Krishnan, Vaibhav Jain, Vipin K Parashar,
  Yang Shi"

* tag 'powerpc-4.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (214 commits)
  powerpc/64s: Power9 has no LPCR[VRMASD] field so don't set it
  powerpc/powernv: Fix TCE kill on NVLink2
  powerpc/mm/radix: Drop support for CPUs without lockless tlbie
  powerpc/book3s/mce: Move add_taint() later in virtual mode
  powerpc/sysfs: Move #ifdef CONFIG_HOTPLUG_CPU out of the function body
  powerpc/smp: Document irq enable/disable after migrating IRQs
  powerpc/mpc52xx: Don't select user-visible RTAS_PROC
  powerpc/powernv: Document cxl dependency on special case in pnv_eeh_reset()
  powerpc/eeh: Clean up and document event handling functions
  powerpc/eeh: Avoid use after free in eeh_handle_special_event()
  cxl: Mask slice error interrupts after first occurrence
  cxl: Route eeh events to all drivers in cxl_pci_error_detected()
  cxl: Force context lock during EEH flow
  powerpc/64: Allow CONFIG_RELOCATABLE if COMPILE_TEST
  powerpc/xmon: Teach xmon oops about radix vectors
  powerpc/mm/hash: Fix off-by-one in comment about kernel contexts ids
  powerpc/pseries: Enable VFIO
  powerpc/powernv: Fix iommu table size calculation hook for small tables
  powerpc/powernv: Check kzalloc() return value in pnv_pci_table_alloc
  powerpc: Add arch/powerpc/tools directory
  ...

Pull namespace updates from Eric Biederman:
 "This is a set of small fixes that were mostly stumbled over during
  more significant development. This proc fix and the fix to
  posix-timers are the most significant of the lot.

  There is a lot of good development going on but unfortunately it
  didn't quite make the merge window"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  proc: Fix unbalanced hard link numbers
  signal: Make kill_proc_info static
  rlimit: Properly call security_task_setrlimit
  signal: Remove unused definition of sig_user_definied
  ia64: Remove unused IA64_TASK_SIGHAND_OFFSET and IA64_SIGHAND_SIGLOCK_OFFSET
  ipc: Remove unused declaration of recompute_msgmni
  posix-timers: Correct sanity check in posix_cpu_nsleep
  sysctl: Remove dead register_sysctl_root

SFM is mapping doublequote to 0xF020

Without this patch creating files with doublequote fails to Windows/Mac

Signed-off-by: Bjoern Jacke <bjacke@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
CC: stable <stable@vger.kernel.org>