nfs_try_to_update_request() should be able to cope now.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Simplify the code, and avoid some flushes to disk.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Both nfs_destroy_unlinked_subrequests() and nfs_lock_and_join_requests()
manipulate the inode flags adjusting the NFS_I(inode)->nrequests.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

We don't want nfs_lock_and_join_requests() to start fiddling with
the request before the call to nfs_page_group_sync_on_bit().
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Request offsets and sizes are not guaranteed to be stable unless you
are holding the request locked.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

All other callers of nfs_page_group_lock() appear to already hold the
page lock on the head page, so doing it in the opposite order here
is inefficient, although not deadlock prone since we roll back all
locks on contention.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Yes, this is a situation that should never happen (hence the WARN_ON)
but we should still ensure that we free up the locks and references to
the faulty pages.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

This fixes a race with nfs_page_group_sync_on_bit() whereby the
call to wake_up_bit() in nfs_page_group_unlock() could occur after
the page header had been freed.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Micro-optimisation to move the lockless check into the for(;;) loop.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Add a lockless check for whether or not the page might be carrying
an existing writeback before we grab the inode->i_lock.
Reported-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

We don't expect the page header lock to ever be held across I/O, so
it should always be safe to wait for it, even if we're doing nonblocking
writebacks.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

The blocklayout code does not compile cleanly for a 32-bit sector_t,
and also has no reliable checks for devices sizes, which makes it
unsafe to use with a kernel that doesn't support large block devices.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reported-by: NArnd Bergmann <arnd@arndb.de>
Fixes: 5c83746a ("pnfs/blocklayout: in-kernel GETDEVICEINFO XDR parsing")
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

This ensures that we see errors on fsync when writeback fails.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>

When the process exit races with outstanding mcopy_atomic, it would be
better to return ESRCH error.  When such race occurs the process and
it's mm are going away and returning "no such process" to the uffd
monitor seems better fit than ENOSPC.

Link: http://lkml.kernel.org/r/1502111545-32305-1-git-send-email-rppt@linux.vnet.ibm.comSigned-off-by: NMike Rapoport <rppt@linux.vnet.ibm.com>
Suggested-by: NMichal Hocko <mhocko@suse.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Nadav reported KSM can corrupt the user data by the TLB batching
race[1].  That means data user written can be lost.

Quote from Nadav Amit:
 "For this race we need 4 CPUs:

  CPU0: Caches a writable and dirty PTE entry, and uses the stale value
  for write later.

  CPU1: Runs madvise_free on the range that includes the PTE. It would
  clear the dirty-bit. It batches TLB flushes.

  CPU2: Writes 4 to /proc/PID/clear_refs , clearing the PTEs soft-dirty.
  We care about the fact that it clears the PTE write-bit, and of
  course, batches TLB flushes.

  CPU3: Runs KSM. Our purpose is to pass the following test in
  write_protect_page():

	if (pte_write(*pvmw.pte) || pte_dirty(*pvmw.pte) ||
	    (pte_protnone(*pvmw.pte) && pte_savedwrite(*pvmw.pte)))

  Since it will avoid TLB flush. And we want to do it while the PTE is
  stale. Later, and before replacing the page, we would be able to
  change the page.

  Note that all the operations the CPU1-3 perform canhappen in parallel
  since they only acquire mmap_sem for read.

  We start with two identical pages. Everything below regards the same
  page/PTE.

  CPU0        CPU1        CPU2        CPU3
  ----        ----        ----        ----
  Write the same
  value on page

  [cache PTE as
   dirty in TLB]

              MADV_FREE
              pte_mkclean()

                          4 > clear_refs
                          pte_wrprotect()

                                      write_protect_page()
                                      [ success, no flush ]

                                      pages_indentical()
                                      [ ok ]

  Write to page
  different value

  [Ok, using stale
   PTE]

                                      replace_page()

  Later, CPU1, CPU2 and CPU3 would flush the TLB, but that is too late.
  CPU0 already wrote on the page, but KSM ignored this write, and it got
  lost"

In above scenario, MADV_FREE is fixed by changing TLB batching API
including [set|clear]_tlb_flush_pending.  Remained thing is soft-dirty
part.

This patch changes soft-dirty uses TLB batching API instead of
flush_tlb_mm and KSM checks pending TLB flush by using
mm_tlb_flush_pending so that it will flush TLB to avoid data lost if
there are other parallel threads pending TLB flush.

[1] http://lkml.kernel.org/r/BD3A0EBE-ECF4-41D4-87FA-C755EA9AB6BD@gmail.com

Link: http://lkml.kernel.org/r/20170802000818.4760-8-namit@vmware.comSigned-off-by: NMinchan Kim <minchan@kernel.org>
Signed-off-by: NNadav Amit <namit@vmware.com>
Reported-by: NNadav Amit <namit@vmware.com>
Tested-by: NNadav Amit <namit@vmware.com>
Reviewed-by: NAndrea Arcangeli <aarcange@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

As Tetsuo points out:
 "Commit 385386cf ("mm: vmstat: move slab statistics from zone to
  node counters") broke "Slab:" field of /proc/meminfo . It shows nearly
  0kB"

In addition to /proc/meminfo, this problem also affects the slab
counters OOM/allocation failure info dumps, can cause early -ENOMEM from
overcommit protection, and miscalculate image size requirements during
suspend-to-disk.

This is because the patch in question switched the slab counters from
the zone level to the node level, but forgot to update the global
accessor functions to read the aggregate node data instead of the
aggregate zone data.

Use global_node_page_state() to access the global slab counters.

Fixes: 385386cf ("mm: vmstat: move slab statistics from zone to node counters")
Link: http://lkml.kernel.org/r/20170801134256.5400-1-hannes@cmpxchg.orgSigned-off-by: NJohannes Weiner <hannes@cmpxchg.org>
Reported-by: NTetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Acked-by: NMichal Hocko <mhocko@suse.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Stefan Agner <stefan@agner.ch>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If the call to TEST_STATEID returns NFS4ERR_OLD_STATEID, then it just
means we raced with other calls to OPEN.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

The client was freeing the nfs4_ff_layout_ds, but not the contained
nfs4_ff_ds_version array.
Signed-off-by: NWeston Andros Adamson <dros@primarydata.com>
Cc: stable@vger.kernel.org # v4.0+
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

This bug was found by a static code checker tool for copy paste
problems.
Signed-off-by: NManinder Singh <maninder1.s@samsung.com>
Signed-off-by: NVaneet Narang <v.narang@samsung.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

On a 32-bit platform, the value of n_blcoks_count may be wrong during
the file system is resized to size larger than 2^32 blocks.  This may
caused the superblock being corrupted with zero blocks count.

Fixes: 1c6bd717Signed-off-by: NJerry Lee <jerrylee@qnap.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org # 3.7+

When upgrading from old format, try to set project id
to old file first time, it will return EOVERFLOW, but if
that file is dirtied(touch etc), changing project id will
be allowed, this might be confusing for users, we could
try to expand @i_extra_isize here too.
Reported-by: NZhang Yi <yi.zhang@huawei.com>
Signed-off-by: NMiao Xie <miaoxie@huawei.com>
Signed-off-by: NWang Shilong <wshilong@ddn.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

Clean up some goto statement, make ext4_expand_extra_isize_ea() clearer.
Signed-off-by: NMiao Xie <miaoxie@huawei.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NWang Shilong <wshilong@ddn.com>

Current ext4_expand_extra_isize just tries to expand extra isize, if
someone is holding xattr lock or some check fails, it will give up.
So rename its name to ext4_try_to_expand_extra_isize.

Besides that, we clean up unnecessary check and move some relative checks
into it.
Signed-off-by: NMiao Xie <miaoxie@huawei.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NWang Shilong <wshilong@ddn.com>

We should avoid the contention between the i_extra_isize update and
the inline data insertion, so move the xattr trylock in front of
i_extra_isize update.
Signed-off-by: NMiao Xie <miaoxie@huawei.com>
Reviewed-by: NWang Shilong <wshilong@ddn.com>

ext4_xattr_inode_read() currently reads each block sequentially while
waiting for io operation to complete before moving on to the next
block. This prevents request merging in block layer.

Add a ext4_bread_batch() function that starts reads for all blocks
then optionally waits for them to complete. A similar logic is used
in ext4_find_entry(), so update that code to use the new function.
Signed-off-by: NTahsin Erdogan <tahsin@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

When an xattr block has a single reference, block is updated inplace
and it is reinserted to the cache. Later, a cache lookup is performed
to see whether an existing block has the same contents. This cache
lookup will most of the time return the just inserted entry so
deduplication is not achieved.

Running the following test script will produce two xattr blocks which
can be observed in "File ACL: " line of debugfs output:

  mke2fs -b 1024 -I 128 -F -O extent /dev/sdb 1G
  mount /dev/sdb /mnt/sdb

  touch /mnt/sdb/{x,y}

  setfattr -n user.1 -v aaa /mnt/sdb/x
  setfattr -n user.2 -v bbb /mnt/sdb/x

  setfattr -n user.1 -v aaa /mnt/sdb/y
  setfattr -n user.2 -v bbb /mnt/sdb/y

  debugfs -R 'stat x' /dev/sdb | cat
  debugfs -R 'stat y' /dev/sdb | cat

This patch defers the reinsertion to the cache so that we can locate
other blocks with the same contents.
Signed-off-by: NTahsin Erdogan <tahsin@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NAndreas Dilger <adilger@dilger.ca>

ext4_alloc_file_blocks() does not use its mode parameter. Remove it.
Signed-off-by: NTahsin Erdogan <tahsin@google.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

After commit 62d1034f53e3 ("fortify: use WARN instead of BUG for now"),
we get a warning about possible stack overflow from a memcpy that
was not strictly bounded to the size of the local variable:

    inlined from 'ext4_mb_seq_groups_show' at fs/ext4/mballoc.c:2322:2:
include/linux/string.h:309:9: error: '__builtin_memcpy': writing between 161 and 1116 bytes into a region of size 160 overflows the destination [-Werror=stringop-overflow=]

We actually had a bug here that would have been found by the warning,
but it was already fixed last year in commit 30a9d7af ("ext4: fix
stack memory corruption with 64k block size").

This replaces the fixed-length structure on the stack with a variable-length
structure, using the correct upper bound that tells the compiler that
everything is really fine here. I also change the loop count to check
for the same upper bound for consistency, but the existing code is
already correct here.

Note that while clang won't allow certain kinds of variable-length arrays
in structures, this particular instance is fine, as the array is at the
end of the structure, and the size is strictly bounded.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

The dir_nlink feature has been enabled by default for new ext4
filesystems since e2fsprogs-1.41 in 2008, and was automatically
enabled by the kernel for older ext4 filesystems since the
dir_nlink feature was added with ext4 in kernel 2.6.28+ when
the subdirectory count exceeded EXT4_LINK_MAX-1.

Automatically adding the file system features such as dir_nlink is
generally frowned upon, since it could cause the file system to not be
mountable on older kernel, thus preventing the administrator from
rolling back to an older kernel if necessary.

In this case, the administrator might also want to disable the feature
because glibc's fts_read() function does not correctly optimize
directory traversal for directories that use st_nlinks field of 1 to
indicate that the number of links in the directory are not tracked by
the file system, and could fail to traverse the full directory
hierarchy.  Fortunately, in the past ten years very few users have
complained about incomplete file system traversal by glibc's
fts_read().

This commit also changes ext4_inc_count() to allow i_nlinks to reach
the full EXT4_LINK_MAX links on the parent directory (including "."
and "..") before changing i_links_count to be 1.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=196405Signed-off-by: NAndreas Dilger <adilger@dilger.ca>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

I get a static checker warning:

    fs/ext4/ext4.h:3091 ext4_set_de_type()
    error: buffer overflow 'ext4_type_by_mode' 15 <= 15

It seems unlikely that we would hit this read overflow in real life, but
it's also simple enough to make the array 16 bytes instead of 15.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>

ext4_find_unwritten_pgoff() does not properly handle a situation when
starting index is in the middle of a page and blocksize < pagesize. The
following command shows the bug on filesystem with 1k blocksize:

  xfs_io -f -c "falloc 0 4k" \
            -c "pwrite 1k 1k" \
            -c "pwrite 3k 1k" \
            -c "seek -a -r 0" foo

In this example, neither lseek(fd, 1024, SEEK_HOLE) nor lseek(fd, 2048,
SEEK_DATA) will return the correct result.

Fix the problem by neglecting buffers in a page before starting offset.
Reported-by: NAndreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Signed-off-by: NJan Kara <jack@suse.cz>
CC: stable@vger.kernel.org # 3.8+

We've changed the discard command handling into parallel manner.
But, in this change, I forgot decreasing the usage count of the bio
which was used to send discard request. I'm sorry about that.

Fixes: a0154344 ("ext4: send parallel discards on commit completions")
Signed-off-by: NDaeho Jeong <daeho.jeong@samsung.com>
Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
Reviewed-by: NJan Kara <jack@suse.cz>

According to the commit that implemented per-inode DAX flag:
commit 58f88ca2 ("xfs: introduce per-inode DAX enablement")
the flag is supposed to act as "inherit flag".

Currently this only works in the situations where parent directory
already has a flag in di_flags set, otherwise inheritance does not
work. This is because setting the XFS_DIFLAG2_DAX flag is done in a
wrong branch designated for di_flags, not di_flags2.

Fix this by moving the code to branch designated for setting di_flags2,
which does test for flags in di_flags2.

Fixes: 58f88ca2 ("xfs: introduce per-inode DAX enablement")
Signed-off-by: NLukas Czerner <lczerner@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

The bio describing discard operation is allocated by
__blkdev_issue_discard() which returns us a reference to it. That
reference is never released and thus we leak this bio. Drop the bio
reference once it completes in xlog_discard_endio().

CC: stable@vger.kernel.org
Fixes: 4560e78fSigned-off-by: NJan Kara <jack@suse.cz>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

Commit 8fba54ae ("fuse: direct-io: don't dirty ITER_BVEC pages") fixes
the ITER_BVEC page deadlock for direct io in fuse by checking in
fuse_direct_io(), whether the page is a bvec page or not, before locking
it.  However, this check is missed when the "async_dio" mount option is
enabled.  In this case, set_page_dirty_lock() is called from the req->end
callback in request_end(), when the fuse thread is returning from userspace
to respond to the read request.  This will cause the same deadlock because
the bvec condition is not checked in this path.

Here is the stack of the deadlocked thread, while returning from userspace:

[13706.656686] INFO: task glusterfs:3006 blocked for more than 120 seconds.
[13706.657808] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables
this message.
[13706.658788] glusterfs       D ffffffff816c80f0     0  3006      1
0x00000080
[13706.658797]  ffff8800d6713a58 0000000000000086 ffff8800d9ad7000
ffff8800d9ad5400
[13706.658799]  ffff88011ffd5cc0 ffff8800d6710008 ffff88011fd176c0
7fffffffffffffff
[13706.658801]  0000000000000002 ffffffff816c80f0 ffff8800d6713a78
ffffffff816c790e
[13706.658803] Call Trace:
[13706.658809]  [<ffffffff816c80f0>] ? bit_wait_io_timeout+0x80/0x80
[13706.658811]  [<ffffffff816c790e>] schedule+0x3e/0x90
[13706.658813]  [<ffffffff816ca7e5>] schedule_timeout+0x1b5/0x210
[13706.658816]  [<ffffffff81073ffb>] ? gup_pud_range+0x1db/0x1f0
[13706.658817]  [<ffffffff810668fe>] ? kvm_clock_read+0x1e/0x20
[13706.658819]  [<ffffffff81066909>] ? kvm_clock_get_cycles+0x9/0x10
[13706.658822]  [<ffffffff810f5792>] ? ktime_get+0x52/0xc0
[13706.658824]  [<ffffffff816c6f04>] io_schedule_timeout+0xa4/0x110
[13706.658826]  [<ffffffff816c8126>] bit_wait_io+0x36/0x50
[13706.658828]  [<ffffffff816c7d06>] __wait_on_bit_lock+0x76/0xb0
[13706.658831]  [<ffffffffa0545636>] ? lock_request+0x46/0x70 [fuse]
[13706.658834]  [<ffffffff8118800a>] __lock_page+0xaa/0xb0
[13706.658836]  [<ffffffff810c8500>] ? wake_atomic_t_function+0x40/0x40
[13706.658838]  [<ffffffff81194d08>] set_page_dirty_lock+0x58/0x60
[13706.658841]  [<ffffffffa054d968>] fuse_release_user_pages+0x58/0x70 [fuse]
[13706.658844]  [<ffffffffa0551430>] ? fuse_aio_complete+0x190/0x190 [fuse]
[13706.658847]  [<ffffffffa0551459>] fuse_aio_complete_req+0x29/0x90 [fuse]
[13706.658849]  [<ffffffffa05471e9>] request_end+0xd9/0x190 [fuse]
[13706.658852]  [<ffffffffa0549126>] fuse_dev_do_write+0x336/0x490 [fuse]
[13706.658854]  [<ffffffffa054963e>] fuse_dev_write+0x6e/0xa0 [fuse]
[13706.658857]  [<ffffffff812a9ef3>] ? security_file_permission+0x23/0x90
[13706.658859]  [<ffffffff81205300>] do_iter_readv_writev+0x60/0x90
[13706.658862]  [<ffffffffa05495d0>] ? fuse_dev_splice_write+0x350/0x350
[fuse]
[13706.658863]  [<ffffffff812062a1>] do_readv_writev+0x171/0x1f0
[13706.658866]  [<ffffffff810b3d00>] ? try_to_wake_up+0x210/0x210
[13706.658868]  [<ffffffff81206361>] vfs_writev+0x41/0x50
[13706.658870]  [<ffffffff81206496>] SyS_writev+0x56/0xf0
[13706.658872]  [<ffffffff810257a1>] ? syscall_trace_leave+0xf1/0x160
[13706.658874]  [<ffffffff816cbb2e>] system_call_fastpath+0x12/0x71

Fix this by making should_dirty a fuse_io_priv parameter that can be
checked in fuse_aio_complete_req().
Reported-by: NTiger Yang <tiger.yang@oracle.com>
Signed-off-by: NAshish Samant <ashish.samant@oracle.com>
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>

When new directory 'DIR1' is created in a directory 'DIR0' with SGID bit
set, DIR1 is expected to have SGID bit set (and owning group equal to
the owning group of 'DIR0').  However when 'DIR0' also has some default
ACLs that 'DIR1' inherits, setting these ACLs will result in SGID bit on
'DIR1' to get cleared if user is not member of the owning group.

Fix the problem by moving posix_acl_update_mode() out of ocfs2_set_acl()
into ocfs2_iop_set_acl().  That way the function will not be called when
inheriting ACLs which is what we want as it prevents SGID bit clearing
and the mode has been properly set by posix_acl_create() anyway.  Also
posix_acl_chmod() that is calling ocfs2_set_acl() takes care of updating
mode itself.

Fixes: 07393101 ("posix_acl: Clear SGID bit when setting file permissions")
Link: http://lkml.kernel.org/r/20170801141252.19675-3-jack@suse.czSigned-off-by: NJan Kara <jack@suse.cz>
Cc: Mark Fasheh <mfasheh@versity.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There may still be threads waiting on event_wqh at the time the
userfault file descriptor is closed.  Flush the events wait-queue to
prevent waiting threads from hanging.

Link: http://lkml.kernel.org/r/1501398127-30419-1-git-send-email-rppt@linux.vnet.ibm.com
Fixes: 9cd75c3c ("userfaultfd: non-cooperative: add ability to report
non-PF events from uffd descriptor")
Signed-off-by: NMike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In the non-cooperative userfaultfd case, the process exit may race with
outstanding mcopy_atomic called by the uffd monitor.  Returning -ENOSPC
instead of -EINVAL when mm is already gone will allow uffd monitor to
distinguish this case from other error conditions.

Unfortunately I overlooked userfaultfd_zeropage when updating
userfaultd_copy().

Link: http://lkml.kernel.org/r/1501136819-21857-1-git-send-email-rppt@linux.vnet.ibm.com
Fixes: 96333187 ("userfaultfd_copy: return -ENOSPC in case mm has gone")
Signed-off-by: NMike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

rpc_clnt_add_xprt() expects the callback function to be synchronous, and
expects to release the transport and switch references itself.

Fixes: 04fa2c6b ("NFS pnfs data server multipath session trunking")
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

The verifier is allocated on the stack, but the EXCHANGE_ID RPC call was
changed to be asynchronous by commit 8d89bd70. If we interrrupt
the call to rpc_wait_for_completion_task(), we can therefore end up
transmitting random stack contents in lieu of the verifier.

Fixes: 8d89bd70 ("NFS setup async exchange_id")
Cc: stable@vger.kernel.org # v4.9+
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>