syzbot found the following crash:

  BUG: KASAN: use-after-free in perf_trace_lock_acquire+0x401/0x530 include/trace/events/lock.h:13
  Read of size 8 at addr ffff8880a5cf2c50 by task syz-executor.0/26173

  CPU: 0 PID: 26173 Comm: syz-executor.0 Not tainted 5.3.0-rc6 #146
  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
  Call Trace:
     perf_trace_lock_acquire+0x401/0x530 include/trace/events/lock.h:13
     trace_lock_acquire include/trace/events/lock.h:13 [inline]
     lock_acquire+0x2de/0x410 kernel/locking/lockdep.c:4411
     __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
     _raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:151
     spin_lock include/linux/spinlock.h:338 [inline]
     shmem_fault+0x5ec/0x7b0 mm/shmem.c:2034
     __do_fault+0x111/0x540 mm/memory.c:3083
     do_shared_fault mm/memory.c:3535 [inline]
     do_fault mm/memory.c:3613 [inline]
     handle_pte_fault mm/memory.c:3840 [inline]
     __handle_mm_fault+0x2adf/0x3f20 mm/memory.c:3964
     handle_mm_fault+0x1b5/0x6b0 mm/memory.c:4001
     do_user_addr_fault arch/x86/mm/fault.c:1441 [inline]
     __do_page_fault+0x536/0xdd0 arch/x86/mm/fault.c:1506
     do_page_fault+0x38/0x590 arch/x86/mm/fault.c:1530
     page_fault+0x39/0x40 arch/x86/entry/entry_64.S:1202

It happens if the VMA got unmapped under us while we dropped mmap_sem
and inode got freed.

Pinning the file if we drop mmap_sem fixes the issue.

Link: http://lkml.kernel.org/r/20190927083908.rhifa4mmaxefc24r@boxSigned-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: syzbot+03ee87124ee05af991bd@syzkaller.appspotmail.com
Acked-by: NJohannes Weiner <hannes@cmpxchg.org>
Reviewed-by: NMatthew Wilcox (Oracle) <willy@infradead.org>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

One of our services is observing hanging ps/top/etc under heavy write
IO, and the task states show this is an mmap_sem priority inversion:

A write fault is holding the mmap_sem in read-mode and waiting for
(heavily cgroup-limited) IO in balance_dirty_pages():

    balance_dirty_pages+0x724/0x905
    balance_dirty_pages_ratelimited+0x254/0x390
    fault_dirty_shared_page.isra.96+0x4a/0x90
    do_wp_page+0x33e/0x400
    __handle_mm_fault+0x6f0/0xfa0
    handle_mm_fault+0xe4/0x200
    __do_page_fault+0x22b/0x4a0
    page_fault+0x45/0x50

Somebody tries to change the address space, contending for the mmap_sem in
write-mode:

    call_rwsem_down_write_failed_killable+0x13/0x20
    do_mprotect_pkey+0xa8/0x330
    SyS_mprotect+0xf/0x20
    do_syscall_64+0x5b/0x100
    entry_SYSCALL_64_after_hwframe+0x3d/0xa2

The waiting writer locks out all subsequent readers to avoid lock
starvation, and several threads can be seen hanging like this:

    call_rwsem_down_read_failed+0x14/0x30
    proc_pid_cmdline_read+0xa0/0x480
    __vfs_read+0x23/0x140
    vfs_read+0x87/0x130
    SyS_read+0x42/0x90
    do_syscall_64+0x5b/0x100
    entry_SYSCALL_64_after_hwframe+0x3d/0xa2

To fix this, do what we do for cache read faults already: drop the
mmap_sem before calling into anything IO bound, in this case the
balance_dirty_pages() function, and return VM_FAULT_RETRY.

Link: http://lkml.kernel.org/r/20190924194238.GA29030@cmpxchg.orgSigned-off-by: NJohannes Weiner <hannes@cmpxchg.org>
Reviewed-by: NMatthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This has confused a significant number of people using cgroups inside
Facebook, and some of those outside as well judging by posts like
this[0] (although it's not a problem unique to cgroup v2).

If shmem handling in particular becomes more coherent at some point in
the future -- although that seems unlikely now -- we can change the
wording here.

[0]: https://unix.stackexchange.com/q/525092/10762

Link: http://lkml.kernel.org/r/20191111144958.GA11914@chrisdown.nameSigned-off-by: NChris Down <chris@chrisdown.name>
Acked-by: NMichal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Roman Gushchin <guro@fb.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since commit 1ba6fc9a ("mm: vmscan: do not share cgroup iteration
between reclaimers"), the memcg reclaim does not bail out earlier based
on sc->nr_reclaimed and will traverse all the nodes.  All the
reclaimable pages of the memcg on all the nodes will be scanned relative
to the reclaim priority.  So, there is no need to maintain state
regarding which node to start the memcg reclaim from.

This patch effectively reverts the commit 889976db ("memcg: reclaim
memory from nodes in round-robin order") and commit 453a9bf3
("memcg: fix numa scan information update to be triggered by memory
event").

[shakeelb@google.com: v2]
  Link: http://lkml.kernel.org/r/20191030204232.139424-1-shakeelb@google.com
Link: http://lkml.kernel.org/r/20191029234753.224143-1-shakeelb@google.comSigned-off-by: NShakeel Butt <shakeelb@google.com>
Acked-by: NRoman Gushchin <guro@fb.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Acked-by: NJohannes Weiner <hannes@cmpxchg.org>
Cc: Greg Thelen <gthelen@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

These comments should be updated as memcg limit enforcement has been
moved from zones to nodes.

Link: http://lkml.kernel.org/r/20191022150618.GA15519@haolee.github.ioSigned-off-by: NHao Lee <haolee.swjtu@gmail.com>
Acked-by: NRoman Gushchin <guro@fb.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Setting a memory.high limit below the usage makes almost no effort to
shrink the cgroup to the new target size.

While memory.high is a "soft" limit that isn't supposed to cause OOM
situations, we should still try harder to meet a user request through
persistent reclaim.

For example, after setting a 10M memory.high on an 800M cgroup full of
file cache, the usage shrinks to about 350M:

  + cat /cgroup/workingset/memory.current
  841568256
  + echo 10M
  + cat /cgroup/workingset/memory.current
  355729408

This isn't exactly what the user would expect to happen. Setting the
value a few more times eventually whittles the usage down to what we
are asking for:

  + echo 10M
  + cat /cgroup/workingset/memory.current
  104181760
  + echo 10M
  + cat /cgroup/workingset/memory.current
  31801344
  + echo 10M
  + cat /cgroup/workingset/memory.current
  10440704

To improve this, add reclaim retry loops to the memory.high write()
callback, similar to what we do for memory.max, to make a reasonable
effort that the usage meets the requested size after the call returns.

Afterwards, a single write() to memory.high is enough in all but extreme
cases:

  + cat /cgroup/workingset/memory.current
  841609216
  + echo 10M
  + cat /cgroup/workingset/memory.current
  10182656

790M is not a reasonable reclaim target to ask of a single reclaim
invocation.  And it wouldn't be reasonable to optimize the reclaim code
for it.  So asking for the full size but retrying is not a bad choice
here: we express our intent, and benefit if reclaim becomes better at
handling larger requests, but we also acknowledge that some of the
deltas we can encounter in memory_high_write() are just too ridiculously
big for a single reclaim invocation to manage.

Link: http://lkml.kernel.org/r/20191022201518.341216-2-hannes@cmpxchg.orgSigned-off-by: NJohannes Weiner <hannes@cmpxchg.org>
Acked-by: NMichal Hocko <mhocko@suse.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When the reclaim loop in memory_max_write() is ^C'd or similar, we set err
to -EINTR.  But we don't return err.  Once the limit is set, we always
return success (nbytes).  Delete the dead code.

Link: http://lkml.kernel.org/r/20191022201518.341216-1-hannes@cmpxchg.orgSigned-off-by: NJohannes Weiner <hannes@cmpxchg.org>
Acked-by: NMichal Hocko <mhocko@suse.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The mem_cgroup_reclaim_cookie is only used in memcg softlimit reclaim now,
and the priority of the reclaim is always 0.  We don't need to define the
iter in struct mem_cgroup_per_node as an array any more.  That could make
the code more clear and save some space.

Link: http://lkml.kernel.org/r/1569897728-1686-1-git-send-email-laoar.shao@gmail.comSigned-off-by: NYafang Shao <laoar.shao@gmail.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This avoids duplicated PageReferenced() calls.  No behavior change.

Link: http://lkml.kernel.org/r/20191016225326.GB12497@wfg-t540p.sh.intel.comSigned-off-by: NFengguang Wu <fengguang.wu@intel.com>
Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Liu Jingqi <jingqi.liu@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

A zoned block device consists of a number of zones.  Zones are either
conventional and accepting random writes or sequential and requiring
that writes be issued in LBA order from each zone write pointer
position.  For the write restriction, zoned block devices are not
suitable for a swap device.  Disallow swapon on them.

[akpm@linux-foundation.org: reflow and reword comment, per Christoph]
Link: http://lkml.kernel.org/r/20191015085814.637837-1-naohiro.aota@wdc.comSigned-off-by: NNaohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: "Theodore Y. Ts'o" <tytso@mit.edu>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix comments of __get_user_pages() and get_user_pages_remote(), make
them more clear.

Link: http://lkml.kernel.org/r/1572443533-3118-1-git-send-email-liuxiang_1999@126.comSigned-off-by: NLiu Xiang <liuxiang_1999@126.com>
Suggested-by: NJohn Hubbard <jhubbard@nvidia.com>
Reviewed-by: NDavid Hildenbrand <david@redhat.com>
Reviewed-by: NJohn Hubbard <jhubbard@nvidia.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

check_and_migrate_cma_pages() was recording the result of
__get_user_pages_locked() in an unsigned "nr_pages" variable.

Because __get_user_pages_locked() returns a signed value that can
include negative errno values, this had the effect of hiding errors.

Change check_and_migrate_cma_pages() implementation so that it uses a
signed variable instead, and propagates the results back to the caller
just as other gup internal functions do.

This was discovered with the help of unsigned_lesser_than_zero.cocci.

Link: http://lkml.kernel.org/r/1571671030-58029-1-git-send-email-zhongjiang@huawei.comSigned-off-by: Nzhong jiang <zhongjiang@huawei.com>
Suggested-by: NJohn Hubbard <jhubbard@nvidia.com>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Reviewed-by: NJohn Hubbard <jhubbard@nvidia.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

generic_file_direct_write() tries to invalidate pagecache after O_DIRECT
write.  Unlike to similar code in dio_complete() this silently ignores
error returned from invalidate_inode_pages2_range().

According to comment this code here because not all filesystems call
dio_complete() to do proper invalidation after O_DIRECT write.  Noticeable
example is a blkdev_direct_IO().

This patch calls dio_warn_stale_pagecache() if invalidation fails.

Link: http://lkml.kernel.org/r/157270038294.4812.2238891109785106069.stgit@buzzSigned-off-by: NKonstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: NJan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This helper prints warning if direct I/O write failed to invalidate cache,
and set EIO at inode to warn usersapce about possible data corruption.

See also commit 5a9d929d ("iomap: report collisions between directio
and buffered writes to userspace").

Direct I/O is supported by non-disk filesystems, for example NFS.  Thus
generic code needs this even in kernel without CONFIG_BLOCK.

Link: http://lkml.kernel.org/r/157270038074.4812.7980855544557488880.stgit@buzzSigned-off-by: NKonstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: NJan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

generic_file_direct_write() invalidates cache at entry.  Second time this
should be done when request completes.  But this function calls second
invalidation at exit unconditionally even for async requests.

This patch skips second invalidation for async requests (-EIOCBQUEUED).

Link: http://lkml.kernel.org/r/157270037850.4812.15036239021726025572.stgit@buzzSigned-off-by: NKonstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: NJan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The function doesn't need to return any value, and the check can be done
in one pass.

There is a behavior change: before the patch, we stop at the first invalid
free object; after the patch, we stop at the first invalid object, free or
in use.  This shouldn't matter because the original behavior isn't
intended anyway.

Link: http://lkml.kernel.org/r/20191108193958.205102-1-yuzhao@google.comSigned-off-by: NYu Zhao <yuzhao@google.com>
Acked-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Slub doesn't use PG_active and PG_error anymore.

Link: http://lkml.kernel.org/r/20191007222023.162256-1-yuzhao@google.comSigned-off-by: NYu Zhao <yuzhao@google.com>
Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
Acked-by: NDavid Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

With commit ad67b74d ("printk: hash addresses printed with %p"), it
is a little bit harder to match the fault addresses printed by
check_bytes_and_report() or slab_pad_check() in the dump because the
fault addresses may not show up in the dump.

Print the offset of the fault addresses to make it easier to match the
incorrect poison or padding values in the dump.

Before: We have to search the "63" in the dump.  If we want to get the
offset of 63, we have to count it from the start of Object dump.

    =============================================================
    BUG kmalloc-128 (Not tainted): Poison overwritten
    -------------------------------------------------------------

    Disabling lock debugging due to kernel taint
    INFO: 0x00000000570da294-0x00000000570da294.
    First byte 0x63 instead of 0x6b
    ...
    INFO: Object 0x000000006ebb3b9e @offset=14208 fp=0x0000000065862488
    Redzone 00000000a6abccff: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
    Redzone 00000000741c16f0: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
    Redzone 0000000061ad278f: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
    Redzone 000000000467c1bd: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
    Redzone 000000008812766b: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
    Redzone 000000003d9b8f25: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
    Redzone 0000000000d80c33: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
    Redzone 00000000867b0d90: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
    Object 000000006ebb3b9e: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
    Object 000000005ea59a9f: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
    Object 000000003ef8bddc: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
    Object 000000008190375d: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
    Object 000000006df7fb32: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
    Object 0000000069474eae: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
    Object 0000000008073b7d: 6b 6b 6b 6b 63 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
    Object 00000000b45ae74d: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b a5

After: We know the fault address is at @offset=1508, and the Object is
at @offset=1408, so we know the fault address is at offset=100 within
the object.

    =========================================================
    BUG kmalloc-128 (Not tainted): Poison overwritten
    ---------------------------------------------------------

    Disabling lock debugging due to kernel taint
    INFO: 0x00000000638ec1d1-0x00000000638ec1d1 @offset=1508.
    First byte 0x63 instead of 0x6b
    ...
    INFO: Object 0x000000008171818d @offset=1408 fp=0x0000000066dae230
    Redzone 00000000e2697ab6: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
    Redzone 0000000064b6a381: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
    Redzone 00000000e413a234: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
    Redzone 0000000004c1dfeb: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
    Redzone 000000009ad24d42: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
    Redzone 000000002a196a23: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
    Redzone 00000000a7b8468a: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
    Redzone 0000000088db6da3: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
    Object 000000008171818d: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
    Object 000000007c4035d4: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
    Object 000000004dd281a4: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
    Object 0000000079121dff: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
    Object 00000000756682a9: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
    Object 0000000053b7e541: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
    Object 0000000091f8d530: 6b 6b 6b 6b 63 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
    Object 000000009c76035c: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b a5

Link: http://lkml.kernel.org/r/20190925140807.20490-1-miles.chen@mediatek.comSigned-off-by: NMiles Chen <miles.chen@mediatek.com>
Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The type of local variable *type* of new_kmalloc_cache() should be enum
kmalloc_cache_type instead of int, so correct it.

Link: http://lkml.kernel.org/r/1569241648-26908-4-git-send-email-lpf.vector@gmail.comSigned-off-by: NPengfei Li <lpf.vector@gmail.com>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Acked-by: NRoman Gushchin <guro@fb.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Pekka Enberg <penberg@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The size of kmalloc can be obtained from kmalloc_info[], so remove
kmalloc_size() that will not be used anymore.

Link: http://lkml.kernel.org/r/1569241648-26908-3-git-send-email-lpf.vector@gmail.comSigned-off-by: NPengfei Li <lpf.vector@gmail.com>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Acked-by: NRoman Gushchin <guro@fb.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Pekka Enberg <penberg@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Patch series "mm, slab: Make kmalloc_info[] contain all types of names", v6.

There are three types of kmalloc, KMALLOC_NORMAL, KMALLOC_RECLAIM
and KMALLOC_DMA.

The name of KMALLOC_NORMAL is contained in kmalloc_info[].name,
but the names of KMALLOC_RECLAIM and KMALLOC_DMA are dynamically
generated by kmalloc_cache_name().

Patch1 predefines the names of all types of kmalloc to save
the time spent dynamically generating names.

These changes make sense, and the time spent by new_kmalloc_cache()
has been reduced by approximately 36.3%.

                         Time spent by new_kmalloc_cache()
                                  (CPU cycles)
5.3-rc7                              66264
5.3-rc7+patch                        42188

This patch (of 3):

There are three types of kmalloc, KMALLOC_NORMAL, KMALLOC_RECLAIM and
KMALLOC_DMA.

The name of KMALLOC_NORMAL is contained in kmalloc_info[].name, but the
names of KMALLOC_RECLAIM and KMALLOC_DMA are dynamically generated by
kmalloc_cache_name().

This patch predefines the names of all types of kmalloc to save the time
spent dynamically generating names.

Besides, remove the kmalloc_cache_name() that is no longer used.

Link: http://lkml.kernel.org/r/1569241648-26908-2-git-send-email-lpf.vector@gmail.comSigned-off-by: NPengfei Li <lpf.vector@gmail.com>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Acked-by: NRoman Gushchin <guro@fb.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The declarations of __block_write_begin_int and guard_bio_eod are needed
from internal.h so include it to fix the following sparse warnings:

  fs/buffer.c:1930:5: warning: symbol '__block_write_begin_int' was not declared. Should it be static?
  fs/buffer.c:2994:6: warning: symbol 'guard_bio_eod' was not declared. Should it be static?

Link: http://lkml.kernel.org/r/20191011170039.16100-1-ben.dooks@codethink.co.ukSigned-off-by: NBen Dooks <ben.dooks@codethink.co.uk>
Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Use true/false for bool return type of has_bh_in_lru().

Link: http://lkml.kernel.org/r/20191029040529.GA7625@sauravSigned-off-by: NSaurav Girepunje <saurav.girepunje@gmail.com>
Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix a static code checker warning:
fs/ocfs2/acl.c:331
	ocfs2_acl_chmod() warn: passing zero to 'PTR_ERR'

Link: http://lkml.kernel.org/r/1dee278b-6c96-eec2-ce76-fe6e07c6e20f@linux.alibaba.com
Fixes: 5ee0fbd5 ("ocfs2: revert using ocfs2_acl_chmod to avoid inode cluster lock hang")
Signed-off-by: NDing Xiang <dingxiang@cmss.chinamobile.com>
Reviewed-by: NJoseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Here are some of the more common spelling mistakes and typos that I've
found while fixing up spelling mistakes in the kernel since July 2019.

Link: http://lkml.kernel.org/r/20191112092142.97989-1-colin.king@canonical.comSigned-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull fsnotify updates from Jan Kara:
 "Three fsnotify cleanups"

* tag 'fsnotify_for_v5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  fsnotify: Add git tree reference to MAINTAINERS
  fsnotify/fdinfo: exportfs_encode_inode_fh() takes pointer as 4th argument
  fsnotify: move declaration of fsnotify_mark_connector_cachep to fsnotify.h

Pull ext2, quota, reiserfs cleanups and fixes from Jan Kara:

 - Refactor the quota on/off kernel internal interfaces (mostly for
   ubifs quota support as ubifs does not want to have inodes holding
   quota information)

 - A few other small quota fixes and cleanups

 - Various small ext2 fixes and cleanups

 - Reiserfs xattr fix and one cleanup

* tag 'for_v5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: (28 commits)
  ext2: code cleanup for descriptor_loc()
  fs/quota: handle overflows of sysctl fs.quota.* and report as unsigned long
  ext2: fix improper function comment
  ext2: code cleanup for ext2_try_to_allocate()
  ext2: skip unnecessary operations in ext2_try_to_allocate()
  ext2: Simplify initialization in ext2_try_to_allocate()
  ext2: code cleanup by calling ext2_group_last_block_no()
  ext2: introduce new helper ext2_group_last_block_no()
  reiserfs: replace open-coded atomic_dec_and_mutex_lock()
  ext2: check err when partial != NULL
  quota: Handle quotas without quota inodes in dquot_get_state()
  quota: Make dquot_disable() work without quota inodes
  quota: Drop dquot_enable()
  fs: Use dquot_load_quota_inode() from filesystems
  quota: Rename vfs_load_quota_inode() to dquot_load_quota_inode()
  quota: Simplify dquot_resume()
  quota: Factor out setup of quota inode
  quota: Check that quota is not dirty before release
  quota: fix livelock in dquot_writeback_dquots
  ext2: don't set *count in the case of failure in ext2_try_to_allocate()
  ...

Pull erofs updates from Gao Xiang:
 "No major kernel updates for this round since I'm fully diving into
  LZMA algorithm internals now to provide high CR XZ algorihm support.
  That needs more work and time for me to get a better compression time.

  Summary:

   - Introduce superblock checksum support

   - Set iowait when waiting I/O for sync decompression path

   - Several code cleanups"

* tag 'erofs-for-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
  erofs: remove unnecessary output in erofs_show_options()
  erofs: drop all vle annotations for runtime names
  erofs: support superblock checksum
  erofs: set iowait for sync decompression
  erofs: clean up decompress queue stuffs
  erofs: get rid of __stagingpage_alloc helper
  erofs: remove dead code since managed cache is now built-in
  erofs: clean up collection handling routines

Pull cifs updates from Steve French:
 "Various smb3 fixes (including 12 for stable) and also features
  (addition of multichannel support)"

* tag '5.5-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6: (41 commits)
  CIFS: fix a white space issue in cifs_get_inode_info()
  cifs: update internal module version number
  cifs: Always update signing key of first channel
  cifs: Fix retrieval of DFS referrals in cifs_mount()
  cifs: Fix potential softlockups while refreshing DFS cache
  cifs: Fix lookup of root ses in DFS referral cache
  cifs: Fix use-after-free bug in cifs_reconnect()
  cifs: dump channel info in DebugData
  smb3: dump in_send and num_waiters stats counters by default
  cifs: try harder to open new channels
  CIFS: Properly process SMB3 lease breaks
  cifs: move cifsFileInfo_put logic into a work-queue
  cifs: try opening channels after mounting
  CIFS: refactor cifs_get_inode_info()
  cifs: switch servers depending on binding state
  cifs: add server param
  cifs: add multichannel mount options and data structs
  cifs: sort interface list by speed
  CIFS: Fix SMB2 oplock break processing
  cifs: don't use 'pre:' for MODULE_SOFTDEP
  ...

Pull f2fs updates from Jaegeuk Kim:
 "In this round, we've introduced fairly small number of patches as below.

  Enhancements:
   - improve the in-place-update IO flow
   - allocate segment to guarantee no GC for pinned files

  Bug fixes:
   - fix updatetime in lazytime mode
   - potential memory leak in f2fs_listxattr
   - record parent inode number in rename2 correctly
   - fix deadlock in f2fs_gc along with atomic writes
   - avoid needless data migration in GC"

* tag 'f2fs-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs:
  f2fs: stop GC when the victim becomes fully valid
  f2fs: expose main_blkaddr in sysfs
  f2fs: choose hardlimit when softlimit is larger than hardlimit in f2fs_statfs_project()
  f2fs: Fix deadlock in f2fs_gc() context during atomic files handling
  f2fs: show f2fs instance in printk_ratelimited
  f2fs: fix potential overflow
  f2fs: fix to update dir's i_pino during cross_rename
  f2fs: support aligned pinned file
  f2fs: avoid kernel panic on corruption test
  f2fs: fix wrong description in document
  f2fs: cache global IPU bio
  f2fs: fix to avoid memory leakage in f2fs_listxattr
  f2fs: check total_segments from devices in raw_super
  f2fs: update multi-dev metadata in resize_fs
  f2fs: mark recovery flag correctly in read_raw_super_block()
  f2fs: fix to update time in lazytime mode

Pull AFS updates from David Howells:
 "Minor cleanups and fix:

   - Minor fix to make some debugging statements display information
     from the correct iov_iter.

   - Rename some members and variables to make things more obvious or
     consistent.

   - Provide a helper to wrap increments of the usage count on the
     afs_read struct.

   - Use scnprintf() to print into a stack buffer rather than sprintf().

   - Remove some set but unused variables"

* tag 'afs-next-20191121' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Remove set but not used variable 'ret'
  afs: Remove set but not used variables 'before', 'after'
  afs: xattr: use scnprintf
  afs: Introduce an afs_get_read() refcount helper
  afs: Rename desc -> req in afs_fetch_data()
  afs: Switch the naming of call->iter and call->_iter
  afs: Use call->_iter not &call->iter in debugging statements

Pull ext4 updates from Ted Ts'o:
 "This merge window saw the the following new featuers added to ext4:

   - Direct I/O via iomap (required the iomap-for-next branch from
     Darrick as a prereq).

   - Support for using dioread-nolock where the block size < page size.

   - Support for encryption for file systems where the block size < page
     size.

   - Rework of journal credits handling so a revoke-heavy workload will
     not cause the journal to run out of space.

   - Replace bit-spinlocks with spinlocks in jbd2

  Also included were some bug fixes and cleanups, mostly to clean up
  corner cases from fuzzed file systems and error path handling"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (59 commits)
  ext4: work around deleting a file with i_nlink == 0 safely
  ext4: add more paranoia checking in ext4_expand_extra_isize handling
  jbd2: make jbd2_handle_buffer_credits() handle reserved handles
  ext4: fix a bug in ext4_wait_for_tail_page_commit
  ext4: bio_alloc with __GFP_DIRECT_RECLAIM never fails
  ext4: code cleanup for get_next_id
  ext4: fix leak of quota reservations
  ext4: remove unused variable warning in parse_options()
  ext4: Enable encryption for subpage-sized blocks
  fs/buffer.c: support fscrypt in block_read_full_page()
  ext4: Add error handling for io_end_vec struct allocation
  jbd2: Fine tune estimate of necessary descriptor blocks
  jbd2: Provide trace event for handle restarts
  ext4: Reserve revoke credits for freed blocks
  jbd2: Make credit checking more strict
  jbd2: Rename h_buffer_credits to h_total_credits
  jbd2: Reserve space for revoke descriptor blocks
  jbd2: Drop jbd2_space_needed()
  jbd2: Account descriptor blocks into t_outstanding_credits
  jbd2: Factor out common parts of stopping and restarting a handle
  ...

Pull splice fix from Darrick Wong:
 "Fix another place in the splice code where a pipe could ask a
  filesystem for a longer read than the pipe actually has free buffer
  space"

* tag 'vfs-5.5-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  splice: only read in as much information as there is pipe buffer space

Pull iomap updates from Darrick Wong:
 "In this release, we hoisted as much of XFS' writeback code into iomap
  as was practicable, refactored the unshare file data function, added
  the ability to perform buffered io copy on write, and tweaked various
  parts of the directio implementation as needed to port ext4's directio
  code (that will be a separate pull).

  Summary:

   - Make iomap_dio_rw callers explicitly tell us if they want us to
     wait

   - Port the xfs writeback code to iomap to complete the buffered io
     library functions

   - Refactor the unshare code to share common pieces

   - Add support for performing copy on write with buffered writes

   - Other minor fixes

   - Fix unchecked return in iomap_bmap

   - Fix a type casting bug in a ternary statement in
     iomap_dio_bio_actor

   - Improve tracepoints for easier diagnostic ability

   - Fix pipe page leakage in directio reads"

* tag 'iomap-5.5-merge-11' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (31 commits)
  iomap: Fix pipe page leakage during splicing
  iomap: trace iomap_appply results
  iomap: fix return value of iomap_dio_bio_actor on 32bit systems
  iomap: iomap_bmap should check iomap_apply return value
  iomap: Fix overflow in iomap_page_mkwrite
  fs/iomap: remove redundant check in iomap_dio_rw()
  iomap: use a srcmap for a read-modify-write I/O
  iomap: renumber IOMAP_HOLE to 0
  iomap: use write_begin to read pages to unshare
  iomap: move the zeroing case out of iomap_read_page_sync
  iomap: ignore non-shared or non-data blocks in xfs_file_dirty
  iomap: always use AOP_FLAG_NOFS in iomap_write_begin
  iomap: remove the unused iomap argument to __iomap_write_end
  iomap: better document the IOMAP_F_* flags
  iomap: enhance writeback error message
  iomap: pass a struct page to iomap_finish_page_writeback
  iomap: cleanup iomap_ioend_compare
  iomap: move struct iomap_page out of iomap.h
  iomap: warn on inline maps in iomap_writepage_map
  iomap: lift the xfs writeback code to iomap
  ...

Pull hmm updates from Jason Gunthorpe:
 "This is another round of bug fixing and cleanup. This time the focus
  is on the driver pattern to use mmu notifiers to monitor a VA range.
  This code is lifted out of many drivers and hmm_mirror directly into
  the mmu_notifier core and written using the best ideas from all the
  driver implementations.

  This removes many bugs from the drivers and has a very pleasing
  diffstat. More drivers can still be converted, but that is for another
  cycle.

   - A shared branch with RDMA reworking the RDMA ODP implementation

   - New mmu_interval_notifier API. This is focused on the use case of
     monitoring a VA and simplifies the process for drivers

   - A common seq-count locking scheme built into the
     mmu_interval_notifier API usable by drivers that call
     get_user_pages() or hmm_range_fault() with the VA range

   - Conversion of mlx5 ODP, hfi1, radeon, nouveau, AMD GPU, and Xen
     GntDev drivers to the new API. This deletes a lot of wonky driver
     code.

   - Two improvements for hmm_range_fault(), from testing done by Ralph"

* tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  mm/hmm: remove hmm_range_dma_map and hmm_range_dma_unmap
  mm/hmm: make full use of walk_page_range()
  xen/gntdev: use mmu_interval_notifier_insert
  mm/hmm: remove hmm_mirror and related
  drm/amdgpu: Use mmu_interval_notifier instead of hmm_mirror
  drm/amdgpu: Use mmu_interval_insert instead of hmm_mirror
  drm/amdgpu: Call find_vma under mmap_sem
  nouveau: use mmu_interval_notifier instead of hmm_mirror
  nouveau: use mmu_notifier directly for invalidate_range_start
  drm/radeon: use mmu_interval_notifier_insert
  RDMA/hfi1: Use mmu_interval_notifier_insert for user_exp_rcv
  RDMA/odp: Use mmu_interval_notifier_insert()
  mm/hmm: define the pre-processor related parts of hmm.h even if disabled
  mm/hmm: allow hmm_range to be used with a mmu_interval_notifier or hmm_mirror
  mm/mmu_notifier: add an interval tree notifier
  mm/mmu_notifier: define the header pre-processor parts even if disabled
  mm/hmm: allow snapshot of the special zero page

Pull drm coherent memory support for vmwgfx from Dave Airlie:
 "This is a separate pull for the mm pagewalking + drm/vmwgfx work
  Thomas did and you were involved in, I've left it separate in case you
  don't feel as comfortable with it as the other stuff.

  It has mm acks/r-b in the right places from what I can see"

* tag 'drm-vmwgfx-coherent-2019-11-29' of git://anongit.freedesktop.org/drm/drm:
  drm/vmwgfx: Add surface dirty-tracking callbacks
  drm/vmwgfx: Implement an infrastructure for read-coherent resources
  drm/vmwgfx: Use an RBtree instead of linked list for MOB resources
  drm/vmwgfx: Implement an infrastructure for write-coherent resources
  mm: Add write-protect and clean utilities for address space ranges
  mm: Add a walk_page_mapping() function to the pagewalk code
  mm: pagewalk: Take the pagetable lock in walk_pte_range()
  mm: Remove BUG_ON mmap_sem not held from xxx_trans_huge_lock()
  drm/ttm: Convert vm callbacks to helpers
  drm/ttm: Remove explicit typecasts of vm_private_data

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux; tag 'dma-mapping-5.5' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping updates from Christoph Hellwig:

 - improve dma-debug scalability (Eric Dumazet)

 - tiny dma-debug cleanup (Dan Carpenter)

 - check for vmap memory in dma_map_single (Kees Cook)

 - check for dma_addr_t overflows in dma-direct when using DMA offsets
   (Nicolas Saenz Julienne)

 - switch the x86 sta2x11 SOC to use more generic DMA code (Nicolas
   Saenz Julienne)

 - fix arm-nommu dma-ranges handling (Vladimir Murzin)

 - use __initdata in CMA (Shyam Saini)

 - replace the bus dma mask with a limit (Nicolas Saenz Julienne)

 - merge the remapping helpers into the main dma-direct flow (me)

 - switch xtensa to the generic dma remap handling (me)

 - various cleanups around dma_capable (me)

 - remove unused dev arguments to various dma-noncoherent helpers (me)

* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux:

* tag 'dma-mapping-5.5' of git://git.infradead.org/users/hch/dma-mapping: (22 commits)
  dma-mapping: treat dev->bus_dma_mask as a DMA limit
  dma-direct: exclude dma_direct_map_resource from the min_low_pfn check
  dma-direct: don't check swiotlb=force in dma_direct_map_resource
  dma-debug: clean up put_hash_bucket()
  powerpc: remove support for NULL dev in __phys_to_dma / __dma_to_phys
  dma-direct: avoid a forward declaration for phys_to_dma
  dma-direct: unify the dma_capable definitions
  dma-mapping: drop the dev argument to arch_sync_dma_for_*
  x86/PCI: sta2x11: use default DMA address translation
  dma-direct: check for overflows on 32 bit DMA addresses
  dma-debug: increase HASH_SIZE
  dma-debug: reorder struct dma_debug_entry fields
  xtensa: use the generic uncached segment support
  dma-mapping: merge the generic remapping helpers into dma-direct
  dma-direct: provide mmap and get_sgtable method overrides
  dma-direct: remove the dma_handle argument to __dma_direct_alloc_pages
  dma-direct: remove __dma_direct_free_pages
  usb: core: Remove redundant vmap checks
  kernel: dma-contiguous: mark CMA parameters __initdata/__initconst
  dma-debug: add a schedule point in debug_dma_dump_mappings()
  ...

Pull generic ioremap support from Christoph Hellwig:
 "This adds the remaining bits for an entirely generic ioremap and
  iounmap to lib/ioremap.c. To facilitate that, it cleans up the giant
  mess of weird ioremap variants we had with no users outside the arch
  code.

  For now just the three newest ports use the code, but there is more
  than a handful others that can be converted without too much work.

  Summary:

   - clean up various obsolete ioremap and iounmap variants

   - add a new generic ioremap implementation and switch csky, nds32 and
     riscv over to it"

* tag 'ioremap-5.5' of git://git.infradead.org/users/hch/ioremap: (21 commits)
  nds32: use generic ioremap
  csky: use generic ioremap
  csky: remove ioremap_cache
  riscv: use the generic ioremap code
  lib: provide a simple generic ioremap implementation
  sh: remove __iounmap
  nios2: remove __iounmap
  hexagon: remove __iounmap
  m68k: rename __iounmap and mark it static
  arch: rely on asm-generic/io.h for default ioremap_* definitions
  asm-generic: don't provide ioremap for CONFIG_MMU
  asm-generic: ioremap_uc should behave the same with and without MMU
  xtensa: clean up ioremap
  x86: Clean up ioremap()
  parisc: remove __ioremap
  nios2: remove __ioremap
  alpha: remove the unused __ioremap wrapper
  hexagon: clean up ioremap
  ia64: rename ioremap_nocache to ioremap_uc
  unicore32: remove ioremap_cached
  ...

Pull more io_uring updates from Jens Axboe:
 "As mentioned in the first pull request, there was a later batch as
  well. This contains fixes to the stuff that already went in, cleanups,
  and a few later additions. In particular, this contains:

   - Cleanups/fixes/unification of the submission and completion path
     (Pavel,me)

   - Linked timeouts improvements (Pavel,me)

   - Error path fixes (me)

   - Fix lookup window where cancellations wouldn't work (me)

   - Improve DRAIN support (Pavel)

   - Fix backlog flushing -EBUSY on submit (me)

   - Add support for connect(2) (me)

   - Fix for non-iter based fixed IO (Pavel)

   - creds inheritance for async workers (me)

   - Disable cmsg/ancillary data for sendmsg/recvmsg (me)

   - Shrink io_kiocb to 3 cachelines (me)

   - NUMA fix for io-wq (Jann)"

* tag 'for-5.5/io_uring-post-20191128' of git://git.kernel.dk/linux-block: (42 commits)
  io_uring: make poll->wait dynamically allocated
  io-wq: shrink io_wq_work a bit
  io-wq: fix handling of NUMA node IDs
  io_uring: use kzalloc instead of kcalloc for single-element allocations
  io_uring: cleanup io_import_fixed()
  io_uring: inline struct sqe_submit
  io_uring: store timeout's sqe->off in proper place
  net: disallow ancillary data for __sys_{send,recv}msg_file()
  net: separate out the msghdr copy from ___sys_{send,recv}msg()
  io_uring: remove superfluous check for sqe->off in io_accept()
  io_uring: async workers should inherit the user creds
  io-wq: have io_wq_create() take a 'data' argument
  io_uring: fix dead-hung for non-iter fixed rw
  io_uring: add support for IORING_OP_CONNECT
  net: add __sys_connect_file() helper
  io_uring: only return -EBUSY for submit on non-flushed backlog
  io_uring: only !null ptr to io_issue_sqe()
  io_uring: simplify io_req_link_next()
  io_uring: pass only !null to io_req_find_next()
  io_uring: remove io_free_req_find_next()
  ...

Graphics APIs like OpenGL 4.4 and Vulkan require the graphics driver
to provide coherent graphics memory, meaning that the GPU sees any
content written to the coherent memory on the next GPU operation that
touches that memory, and the CPU sees any content written by the GPU
to that memory immediately after any fence object trailing the GPU
operation is signaled.

Paravirtual drivers that otherwise require explicit synchronization
needs to do this by hooking up dirty tracking to pagefault handlers
and buffer object validation.

Provide mm helpers needed for this and that also allow for huge pmd-
and pud entries (patch 1-3), and the associated vmwgfx code (patch 4-7).

The code has been tested and exercised by a tailored version of mesa
where we disable all explicit synchronization and assume graphics memory
is coherent. The performance loss varies of course; a typical number is
around 5%.
Signed-off-by: NDave Airlie <airlied@redhat.com>
From: Thomas Hellstrom <thomas_os@shipmail.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20191113131639.4653-1-thomas_os@shipmail.org