Commit Graph

5014 Commits

Author SHA1 Message Date
Linus Torvalds 80aa76bcd3 Changes since last update:
- Cleanup unnecessary function call parameters
 - Fix a use-after-free bug when aborting logging intents
 - Refactor filestreams state data to avoid use-after-free bug
 - Fix incorrect removal of cow extents when truncating extended
   attributes.
 - Refactor open-coded __set_page_dirty in favor of using vfs function.
 - Fix a deadlock when fstrim and fs shutdown race.
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Merge tag 'xfs-4.17-merge-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull more xfs updates from Darrick Wong:
 "Most of these are code cleanups, but there are a couple of notable
  use-after-free bug fixes.

  This series has been run through a full xfstests run over the week and
  through a quick xfstests run against this morning's master, with no
  major failures reported.

   - clean up unnecessary function call parameters

   - fix a use-after-free bug when aborting logging intents

   - refactor filestreams state data to avoid use-after-free bug

   - fix incorrect removal of cow extents when truncating extended
     attributes.

   - refactor open-coded __set_page_dirty in favor of using vfs
     function.

   - fix a deadlock when fstrim and fs shutdown race"

* tag 'xfs-4.17-merge-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  Force log to disk before reading the AGF during a fstrim
  Export __set_page_dirty
  xfs: only cancel cow blocks when truncating the data fork
  xfs: non-scrub - remove unused function parameters
  xfs: remove filestream item xfs_inode reference
  xfs: fix intent use-after-free on abort
  xfs: Remove "committed" argument of xfs_dir_ialloc
2018-04-12 13:28:22 -07:00
Matthew Wilcox f82b376413 export __set_page_dirty
XFS currently contains a copy-and-paste of __set_page_dirty().  Export
it from buffer.c instead.

Link: http://lkml.kernel.org/r/20180313132639.17387-6-willy@infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:39 -07:00
Carlos Maiolino 8c81dd46ef Force log to disk before reading the AGF during a fstrim
Forcing the log to disk after reading the agf is wrong, we might be
calling xfs_log_force with XFS_LOG_SYNC with a metadata lock held.

This can cause a deadlock when racing a fstrim with a filesystem
shutdown.

The deadlock has been identified due a miscalculation bug in device-mapper
dm-thin, which returns lack of space to its users earlier than the device itself
really runs out of space, changing the device-mapper volume into an error state.

The problem happened while filling the filesystem with a single file,
triggering the bug in device-mapper, consequently causing an IO error
and shutting down the filesystem.

If such file is removed, and fstrim executed before the XFS finishes the
shut down process, the fstrim process will end up holding the buffer
lock, and going to sleep on the cil wait queue.

At this point, the shut down process will try to wake up all the threads
waiting on the cil wait queue, but for this, it will try to hold the
same buffer log already held my the fstrim, locking up the filesystem.

Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-04-10 22:39:04 -07:00
Matthew Wilcox fbbb450904 Export __set_page_dirty
XFS currently contains a copy-and-paste of __set_page_dirty().  Export
it from buffer.c instead.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-04-10 22:39:01 -07:00
Linus Torvalds 9f3a0941fb libnvdimm for 4.17
* A rework of the filesytem-dax implementation provides for detection of
   unmap operations (truncate / hole punch) colliding with in-progress
   device-DMA. A fix for these collisions remains a work-in-progress
   pending resolution of truncate latency and starvation regressions.
 
 * The of_pmem driver expands the users of libnvdimm outside of x86 and
   ACPI to describe an implementation of persistent memory on PowerPC with
   Open Firmware / Device tree.
 
 * Address Range Scrub (ARS) handling is completely rewritten to account for
   the fact that ARS may run for 100s of seconds and there is no platform
   defined way to cancel it. ARS will now no longer block namespace
   initialization.
 
 * The NVDIMM Namespace Label implementation is updated to handle label
   areas as small as 1K, down from 128K.
 
 * Miscellaneous cleanups and updates to unit test infrastructure.
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Merge tag 'libnvdimm-for-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dan Williams:
 "This cycle was was not something I ever want to repeat as there were
  several late changes that have only now just settled.

  Half of the branch up to commit d2c997c0f1 ("fs, dax: use
  page->mapping to warn...") have been in -next for several releases.
  The of_pmem driver and the address range scrub rework were late
  arrivals, and the dax work was scaled back at the last moment.

  The of_pmem driver missed a previous merge window due to an oversight.
  A sense of obligation to rectify that miss is why it is included for
  4.17. It has acks from PowerPC folks. Stephen reported a build failure
  that only occurs when merging it with your latest tree, for now I have
  fixed that up by disabling modular builds of of_pmem. A test merge
  with your tree has received a build success report from the 0day robot
  over 156 configs.

  An initial version of the ARS rework was submitted before the merge
  window. It is self contained to libnvdimm, a net code reduction, and
  passing all unit tests.

  The filesystem-dax changes are based on the wait_var_event()
  functionality from tip/sched/core. However, late review feedback
  showed that those changes regressed truncate performance to a large
  degree. The branch was rewound to drop the truncate behavior change
  and now only includes preparation patches and cleanups (with full acks
  and reviews). The finalization of this dax-dma-vs-trnucate work will
  need to wait for 4.18.

  Summary:

   - A rework of the filesytem-dax implementation provides for detection
     of unmap operations (truncate / hole punch) colliding with
     in-progress device-DMA. A fix for these collisions remains a
     work-in-progress pending resolution of truncate latency and
     starvation regressions.

   - The of_pmem driver expands the users of libnvdimm outside of x86
     and ACPI to describe an implementation of persistent memory on
     PowerPC with Open Firmware / Device tree.

   - Address Range Scrub (ARS) handling is completely rewritten to
     account for the fact that ARS may run for 100s of seconds and there
     is no platform defined way to cancel it. ARS will now no longer
     block namespace initialization.

   - The NVDIMM Namespace Label implementation is updated to handle
     label areas as small as 1K, down from 128K.

   - Miscellaneous cleanups and updates to unit test infrastructure"

* tag 'libnvdimm-for-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (39 commits)
  libnvdimm, of_pmem: workaround OF_NUMA=n build error
  nfit, address-range-scrub: add module option to skip initial ars
  nfit, address-range-scrub: rework and simplify ARS state machine
  nfit, address-range-scrub: determine one platform max_ars value
  powerpc/powernv: Create platform devs for nvdimm buses
  doc/devicetree: Persistent memory region bindings
  libnvdimm: Add device-tree based driver
  libnvdimm: Add of_node to region and bus descriptors
  libnvdimm, region: quiet region probe
  libnvdimm, namespace: use a safe lookup for dimm device name
  libnvdimm, dimm: fix dpa reservation vs uninitialized label area
  libnvdimm, testing: update the default smart ctrl_temperature
  libnvdimm, testing: Add emulation for smart injection commands
  nfit, address-range-scrub: introduce nfit_spa->ars_state
  libnvdimm: add an api to cast a 'struct nd_region' to its 'struct device'
  nfit, address-range-scrub: fix scrub in-progress reporting
  dax, dm: allow device-mapper to operate without dax support
  dax: introduce CONFIG_DAX_DRIVER
  fs, dax: use page->mapping to warn if truncate collides with a busy page
  ext2, dax: introduce ext2_dax_aops
  ...
2018-04-10 10:25:57 -07:00
Darrick J. Wong 4919d42ab6 xfs: only cancel cow blocks when truncating the data fork
In xfs_itruncate_extents, only cancel cow blocks and clear the reflink
flag if we were asked to truncate the data fork.  Attr fork blocks
cannot be shared, so this makes no sense.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2018-04-10 08:28:33 -07:00
Dan Williams e13e75b86e Merge branch 'for-4.17/dax' into libnvdimm-for-next 2018-04-09 10:50:17 -07:00
Eric Sandeen a1f69417c6 xfs: non-scrub - remove unused function parameters
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-04-09 10:23:42 -07:00
Christoph Hellwig 7fcd3efa1e xfs: remove filestream item xfs_inode reference
The filestreams allocator stores an xfs_fstrm_item structure in the MRU to
cache inode number to agno mappings for a particular length of time.  Each
xfs_fstrm_item contains the internal MRU structure, an inode pointer and
agno value.

The inode pointer stored in the xfs_fstrm_item is not referenced, however,
which means the inode itself can be removed and reclaimed before the MRU
item is freed. If this occurs, xfs_fstrm_free_func() can access freed or
unrelated memory through xfs_fstrm_item->ip and crash.

The obvious solution is to grab an inode reference for xfs_fstrm_item.
The filestream mechanism only actually uses the inode pointer as a means
to access the xfs_mount, however.  Rather than add unnecessary
complexity, simplify the implementation to store an xfs_mount pointer in
struct xfs_mru_cache, and pass it to the free callback.  This also
requires updates to the tracepoint class to provide the associated data
via parameters rather than the inode and a minor hack to peek at the MRU
key to establish the inode number at free time.

Based on debugging work and an earlier patch from Brian Foster, who
also wrote most of this changelog.

Reported-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-04-09 10:23:39 -07:00
Linus Torvalds 9022ca6b11 Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc vfs updates from Al Viro:
 "Assorted stuff, including Christoph's I_DIRTY patches"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: move I_DIRTY_INODE to fs.h
  ubifs: fix bogus __mark_inode_dirty(I_DIRTY_SYNC | I_DIRTY_DATASYNC) call
  ntfs: fix bogus __mark_inode_dirty(I_DIRTY_SYNC | I_DIRTY_DATASYNC) call
  gfs2: fix bogus __mark_inode_dirty(I_DIRTY_SYNC | I_DIRTY_DATASYNC) calls
  fs: fold open_check_o_direct into do_dentry_open
  vfs: Replace stray non-ASCII homoglyph characters with their ASCII equivalents
  vfs: make sure struct filename->iname is word-aligned
  get rid of pointless includes of fs_struct.h
  [poll] annotate SAA6588_CMD_POLL users
2018-04-06 11:07:08 -07:00
Linus Torvalds 672a9c1069 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree updates from Jiri Kosina.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
  kfifo: fix inaccurate comment
  tools/thermal: tmon: fix for segfault
  net: Spelling s/stucture/structure/
  edd: don't spam log if no EDD information is present
  Documentation: Fix early-microcode.txt references after file rename
  tracing: Block comments should align the * on each line
  treewide: Fix typos in printk
  GenWQE: Fix a typo in two comments
  treewide: Align function definition open/close braces
2018-04-05 11:56:35 -07:00
Dave Chinner 0612d11663 xfs: fix intent use-after-free on abort
When an intent is aborted during it's initial commit through
xfs_defer_trans_abort(), there is a use after free. The current
report is for a RUI  through this path in generic/388:

 Freed by task 6274:
  __kasan_slab_free+0x136/0x180
  kmem_cache_free+0xe7/0x4b0
  xfs_trans_free_items+0x198/0x2e0
  __xfs_trans_commit+0x27f/0xcc0
  xfs_trans_roll+0x17b/0x2a0
  xfs_defer_trans_roll+0x6ad/0xe60
  xfs_defer_finish+0x2a6/0x2140
  xfs_alloc_file_space+0x53a/0xf90
  xfs_file_fallocate+0x5c6/0xac0
  vfs_fallocate+0x2f5/0x930
  ioctl_preallocate+0x1dc/0x320
  do_vfs_ioctl+0xfe4/0x1690

The problem is that the RUI has two active references - one in the
current transaction, and another held by the defer_ops structure
that is passed to the RUD (intent done) so that both the intent and
the intent done structures are freed on commit of the intent done.

Hence during abort, we need to release the intent item, because the
defer_ops reference is released separately via ->abort_intent
callback. Fix all the intent code to do this correctly.

Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-04-02 20:08:27 -07:00
Chandan Rajendra c959025eda xfs: Remove "committed" argument of xfs_dir_ialloc
xfs_dir_ialloc() rolls the current transaction when allocation of a new
inode required the space manager to perform an allocation and replinish
the Inode btree.

None of the callers of xfs_dir_ialloc() need to know if the
transaction was committed. Hence this commit removes the "committed"
argument of xfs_dir_ialloc.

Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-04-02 15:47:43 -07:00
Dan Williams 6e2608dfd9 xfs, dax: introduce xfs_dax_aops
In preparation for the dax implementation to start associating dax pages
to inodes via page->mapping, we need to provide a 'struct
address_space_operations' instance for dax. Otherwise, direct-I/O
triggers incorrect page cache assumptions and warnings like the
following:

 WARNING: CPU: 27 PID: 1783 at fs/xfs/xfs_aops.c:1468
 xfs_vm_set_page_dirty+0xf3/0x1b0 [xfs]
 [..]
 CPU: 27 PID: 1783 Comm: dma-collision Tainted: G           O 4.15.0-rc2+ #984
 [..]
 Call Trace:
  set_page_dirty_lock+0x40/0x60
  bio_set_pages_dirty+0x37/0x50
  iomap_dio_actor+0x2b7/0x3b0
  ? iomap_dio_zero+0x110/0x110
  iomap_apply+0xa4/0x110
  iomap_dio_rw+0x29e/0x3b0
  ? iomap_dio_zero+0x110/0x110
  ? xfs_file_dio_aio_read+0x7c/0x1a0 [xfs]
  xfs_file_dio_aio_read+0x7c/0x1a0 [xfs]
  xfs_file_read_iter+0xa0/0xc0 [xfs]
  __vfs_read+0xf9/0x170
  vfs_read+0xa6/0x150
  SyS_pread64+0x93/0xb0
  entry_SYSCALL_64_fastpath+0x1f/0x96

...where the default set_page_dirty() handler assumes that dirty state
is being tracked in 'struct page' flags.

Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Suggested-by: Jan Kara <jack@suse.cz>
Suggested-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-03-30 11:34:55 -07:00
Eric Sandeen dc1baa715b xfs: do not log/recover swapext extent owner changes for deleted inodes
Today if we run xfs_fsr and crash[1], log replay can fail because
the recovery code tries to instantiate the donor inode from
disk to replay the swapext, but it's been deleted and we get
verifier failures when we try to read the inode off disk with
i_mode == 0.

This fixes both sides: We don't log the swapext change if the
inode has been deleted, and we don't try to recover it either.

[1] or if systemd doesn't cleanly unmount root, as it is wont
    to do ...

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-03-29 10:19:15 -07:00
Brian Foster 72c44e35f0 xfs: clean up xfs_mount allocation and dynamic initializers
Most of the generic data structures embedded in xfs_mount are
dynamically initialized immediately after mp is allocated. A few
fields are left out and initialized during the xfs_mountfs()
sequence, after mp has been attached to the superblock.

To clean this up and help prevent premature access of associated
fields, refactor xfs_mount allocation and all dependent init calls
into a new helper. This self-documents that all low level data
structures (i.e., locks, trees, etc.) should be initialized before
xfs_mount is attached to the superblock.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-03-26 08:54:15 -07:00
Joe Perches 447a5647c9 treewide: Align function definition open/close braces
Some functions definitions have either the initial open brace and/or
the closing brace outside of column 1.

Move those braces to column 1.

This allows various function analyzers like gnu complexity to work
properly for these modified functions.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Nicolin Chen <nicoleotsuka@gmail.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2018-03-26 11:13:09 +02:00
Dave Chinner fa4493f0d9 xfs: remove dead inode version setting code
We can only get into the branch if CRCs are enabled, so there's no
need to check inside the branch for CRCs being enabled....

Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-03-23 18:05:09 -07:00
Dave Chinner ee457001ed xfs: catch inode allocation state mismatch corruption
We recently came across a V4 filesystem causing memory corruption
due to a newly allocated inode being setup twice and being added to
the superblock inode list twice. From code inspection, the only way
this could happen is if a newly allocated inode was not marked as
free on disk (i.e. di_mode wasn't zero).

Running the metadump on an upstream debug kernel fails during inode
allocation like so:

XFS: Assertion failed: ip->i_d.di_nblocks == 0, file: fs/xfs/xfs_inod=
e.c, line: 838
 ------------[ cut here ]------------
kernel BUG at fs/xfs/xfs_message.c:114!
invalid opcode: 0000 [#1] PREEMPT SMP
CPU: 11 PID: 3496 Comm: mkdir Not tainted 4.16.0-rc5-dgc #442
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/0=
1/2014
RIP: 0010:assfail+0x28/0x30
RSP: 0018:ffffc9000236fc80 EFLAGS: 00010202
RAX: 00000000ffffffea RBX: 0000000000004000 RCX: 0000000000000000
RDX: 00000000ffffffc0 RSI: 000000000000000a RDI: ffffffff8227211b
RBP: ffffc9000236fce8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000bec R11: f000000000000000 R12: ffffc9000236fd30
R13: ffff8805c76bab80 R14: ffff8805c77ac800 R15: ffff88083fb12e10
FS:  00007fac8cbff040(0000) GS:ffff88083fd00000(0000) knlGS:0000000000000=
000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffa6783ff8 CR3: 00000005c6e2b003 CR4: 00000000000606e0
Call Trace:
 xfs_ialloc+0x383/0x570
 xfs_dir_ialloc+0x6a/0x2a0
 xfs_create+0x412/0x670
 xfs_generic_create+0x1f7/0x2c0
 ? capable_wrt_inode_uidgid+0x3f/0x50
 vfs_mkdir+0xfb/0x1b0
 SyS_mkdir+0xcf/0xf0
 do_syscall_64+0x73/0x1a0
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

Extracting the inode number we crashed on from an event trace and
looking at it with xfs_db:

xfs_db> inode 184452204
xfs_db> p
core.magic = 0x494e
core.mode = 0100644
core.version = 2
core.format = 2 (extents)
core.nlinkv2 = 1
core.onlink = 0
.....

Confirms that it is not a free inode on disk. xfs_repair
also trips over this inode:

.....
zero length extent (off = 0, fsbno = 0) in ino 184452204
correcting nextents for inode 184452204
bad attribute fork in inode 184452204, would clear attr fork
bad nblocks 1 for inode 184452204, would reset to 0
bad anextents 1 for inode 184452204, would reset to 0
imap claims in-use inode 184452204 is free, would correct imap
would have cleared inode 184452204
.....
disconnected inode 184452204, would move to lost+found

And so we have a situation where the directory structure and the
inobt thinks the inode is free, but the inode on disk thinks it is
still in use. Where this corruption came from is not possible to
diagnose, but we can detect it and prevent the kernel from oopsing
on lookup. The reproducer now results in:

$ sudo mkdir /mnt/scratch/{0,1,2,3,4,5}{0,1,2,3,4,5}
mkdir: cannot create directory =E2=80=98/mnt/scratch/00=E2=80=99: File ex=
ists
mkdir: cannot create directory =E2=80=98/mnt/scratch/01=E2=80=99: File ex=
ists
mkdir: cannot create directory =E2=80=98/mnt/scratch/03=E2=80=99: Structu=
re needs cleaning
mkdir: cannot create directory =E2=80=98/mnt/scratch/04=E2=80=99: Input/o=
utput error
mkdir: cannot create directory =E2=80=98/mnt/scratch/05=E2=80=99: Input/o=
utput error
....

And this corruption shutdown:

[   54.843517] XFS (loop0): Corruption detected! Free inode 0xafe846c not=
 marked free on disk
[   54.845885] XFS (loop0): Internal error xfs_trans_cancel at line 1023 =
of file fs/xfs/xfs_trans.c.  Caller xfs_create+0x425/0x670
[   54.848994] CPU: 10 PID: 3541 Comm: mkdir Not tainted 4.16.0-rc5-dgc #=
443
[   54.850753] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIO=
S 1.10.2-1 04/01/2014
[   54.852859] Call Trace:
[   54.853531]  dump_stack+0x85/0xc5
[   54.854385]  xfs_trans_cancel+0x197/0x1c0
[   54.855421]  xfs_create+0x425/0x670
[   54.856314]  xfs_generic_create+0x1f7/0x2c0
[   54.857390]  ? capable_wrt_inode_uidgid+0x3f/0x50
[   54.858586]  vfs_mkdir+0xfb/0x1b0
[   54.859458]  SyS_mkdir+0xcf/0xf0
[   54.860254]  do_syscall_64+0x73/0x1a0
[   54.861193]  entry_SYSCALL_64_after_hwframe+0x42/0xb7
[   54.862492] RIP: 0033:0x7fb73bddf547
[   54.863358] RSP: 002b:00007ffdaa553338 EFLAGS: 00000246 ORIG_RAX: 0000=
000000000053
[   54.865133] RAX: ffffffffffffffda RBX: 00007ffdaa55449a RCX: 00007fb73=
bddf547
[   54.866766] RDX: 0000000000000001 RSI: 00000000000001ff RDI: 00007ffda=
a55449a
[   54.868432] RBP: 00007ffdaa55449a R08: 00000000000001ff R09: 00005623a=
8670dd0
[   54.870110] R10: 00007fb73be72d5b R11: 0000000000000246 R12: 000000000=
00001ff
[   54.871752] R13: 00007ffdaa5534b0 R14: 0000000000000000 R15: 00007ffda=
a553500
[   54.873429] XFS (loop0): xfs_do_force_shutdown(0x8) called from line 1=
024 of file fs/xfs/xfs_trans.c.  Return address = ffffffff814cd050
[   54.882790] XFS (loop0): Corruption of in-memory data detected.  Shutt=
ing down filesystem
[   54.884597] XFS (loop0): Please umount the filesystem and rectify the =
problem(s)

Note that this crash is only possible on v4 filesystemsi or v5
filesystems mounted with the ikeep mount option. For all other V5
filesystems, this problem cannot occur because we don't read inodes
we are allocating from disk - we simply overwrite them with the new
inode information.

Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Tested-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-03-23 18:05:09 -07:00
Darrick J. Wong b83e4c3ced xfs: xfs_scrub_iallocbt_xref_rmap_inodes should use xref_set_corrupt
In xfs_scrub_iallocbt_xref_rmap_inodes we're checking inodes against
rmap records, so we should use xfs_scrub_btree_xref_set_corrupt if we
encounter discrepancies here so that we know that it's a cross
referencing error, not necessarily a corruption in the inobt itself.

The userspace xfs_scrub program will try to repair outright corruptions
in the agi/inobt prior to phase 3 so that the inode scan will proceed.
If only a cross-referencing error is noted, the repair program defers
the repair attempt until it can check the other space metadata at least
once.

It is therefore essential that the inobt scrubber can correctly
distinguish between corruptions and "unable to cross-reference something
else with this inobt".  The same reasoning applies to "xfs: record inode
buf errors as a xref error in inobt scrubber".

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-03-23 18:05:09 -07:00
Darrick J. Wong 5927268f5a xfs: flag inode corruption if parent ptr doesn't get us a real inode
If a directory's parent inode pointer doesn't point to an inode, the
directory should be flagged as corrupt.  Enable IGET_UNTRUSTED here so
that _iget will return -EINVAL if the inobt does not confirm that the
inode is present and allocated and we can flag the directory corruption.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-03-23 18:05:08 -07:00
Darrick J. Wong 6a96c56505 xfs: don't accept inode buffers with suspicious unlinked chains
When we're verifying inode buffers, sanity-check the unlinked pointer.
We don't want to run the risk of trying to purge something that's
obviously broken.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-03-23 18:05:08 -07:00
Darrick J. Wong 8bb82bc12a xfs: move inode extent size hint validation to libxfs
Extent size hint validation is used by scrub to decide if there's an
error, and it will be used by repair to decide to remove the hint.
Since these use the same validation functions, move them to libxfs.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-03-23 18:05:08 -07:00
Darrick J. Wong 1b44a6aecc xfs: record inode buf errors as a xref error in inobt scrubber
During the inode btree scrubs we try to confirm the freemask bits
against the inode records.  If the inode buffer read fails, this is a
cross-referencing error, not a corruption of the inode btree itself.
Use the xref_process_error call here.  Found via core.version middlebit
fuzz in xfs/415.

The userspace xfs_scrub program will try to repair outright corruptions
in the agi/inobt prior to phase 3 so that the inode scan will proceed.
If only a cross-referencing error is noted, the repair program defers
the repair attempt until it can check the other space metadata at least
once.

It is therefore essential that the inobt scrubber can correctly
distinguish between corruptions and "unable to cross-reference something
else with this inobt".

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-03-23 18:05:08 -07:00
Darrick J. Wong 7e56d9eaea xfs: remove xfs_buf parameter from inode scrub methods
Now that we no longer do raw inode buffer scrubbing, the bp parameter is
no longer used anywhere we're dealing with an inode, so remove it and
all the useless NULL parameters that go with it.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-03-23 18:05:08 -07:00
Darrick J. Wong d0018ad889 xfs: inode scrubber shouldn't bother with raw checks
The inode scrubber tries to _iget the inode prior to running checks.
If that _iget call fails with corruption errors that's an automatic
fail, regardless of whether it was the inode buffer read verifier,
the ifork verifier, or the ifork formatter that errored out.

Therefore, get rid of the raw mode scrub code because it's not needed.
Found by trying to fix some test failures in xfs/379 and xfs/415.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-03-23 18:05:08 -07:00
Darrick J. Wong 5e777b62b0 xfs: bmap scrubber should do rmap xref with bmap for sparse files
When we're scanning an extent mapping inode fork, ensure that every rmap
record for this ifork has a corresponding bmbt record too.  This
(mostly) provides the ability to cross-reference rmap records with bmap
data.  The rmap scrubber cannot do the xref on its own because that
requires taking an ilock with the agf lock held, which violates our
locking order rules (inode, then agf).

Note that we only do this for forks that are in btree format due to the
increased complexity; or forks that should have data but suspiciously
have zero extents because the inode could have just had its iforks
zapped by the inode repair code and now we need to reclaim the old
extents.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-03-23 18:05:07 -07:00
Darrick J. Wong 6edb181053 xfs: refactor inode buffer verifier error logging
When the inode buffer verifier encounters an error, it's much more
helpful to print a buffer from the offending inode instead of just the
start of the inode chunk buffer.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-03-23 18:05:07 -07:00
Darrick J. Wong 90a58f9571 xfs: refactor inode verifier error logging
Refactor some of the inode verifier failure logging call sites to use
the new xfs_inode_verifier_error method which dumps the offending buffer
as well as the code location of the failed check.  This trims the
output, makes it clearer to the admin that repair must be run, and gives
the developers more details to work from.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-03-23 18:05:07 -07:00
Darrick J. Wong 30b0984d91 xfs: refactor bmap record validation
Refactor the bmap validator into a more complete helper that looks for
extents that run off the end of the device, overflow into the next AG,
or have invalid flag states.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-03-23 18:05:07 -07:00
Darrick J. Wong 6915ef35c0 xfs: sanity-check the unused space before trying to use it
In xfs_dir2_data_use_free, we examine on-disk metadata and ASSERT if
it doesn't make sense.  Since a carefully crafted fuzzed image can cause
the kernel to crash after blowing a bunch of assertions, let's move
those checks into a validator function and rig everything up to return
EFSCORRUPTED to userspace.  Found by lastbit fuzzing ltail.bestcount via
xfs/391.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2018-03-23 18:05:07 -07:00
Brian Foster a27ba2607e xfs: detect agfl count corruption and reset agfl
The struct xfs_agfl v5 header was originally introduced with
unexpected padding that caused the AGFL to operate with one less
slot than intended. The header has since been packed, but the fix
left an incompatibility for users who upgrade from an old kernel
with the unpacked header to a newer kernel with the packed header
while the AGFL happens to wrap around the end. The newer kernel
recognizes one extra slot at the physical end of the AGFL that the
previous kernel did not. The new kernel will eventually attempt to
allocate a block from that slot, which contains invalid data, and
cause a crash.

This condition can be detected by comparing the active range of the
AGFL to the count. While this detects a padding mismatch, it can
also trigger false positives for unrelated flcount corruption. Since
we cannot distinguish a size mismatch due to padding from unrelated
corruption, we can't trust the AGFL enough to simply repopulate the
empty slot.

Instead, avoid unnecessarily complex detection logic and and use a
solution that can handle any form of flcount corruption that slips
through read verifiers: distrust the entire AGFL and reset it to an
empty state. Any valid blocks within the AGFL are intentionally
leaked. This requires xfs_repair to rectify (which was already
necessary based on the state the AGFL was found in). The reset
mitigates the side effect of the padding mismatch problem from a
filesystem crash to a free space accounting inconsistency. The
generic approach also means that this patch can be safely backported
to kernels with or without a packed struct xfs_agfl.

Check the AGF for an invalid freelist count on initial read from
disk. If detected, set a flag on the xfs_perag to indicate that a
reset is required before the AGFL can be used. In the first
transaction that attempts to use a flagged AGFL, reset it to empty,
warn the user about the inconsistency and allow the freelist fixup
code to repopulate the AGFL with new blocks. The xfs_perag flag is
cleared to eliminate the need for repeated checks on each block
allocation operation.

This allows kernels that include the packing fix commit 96f859d52b
("libxfs: pack the agfl header structure so XFS_AGFL_SIZE is correct")
to handle older unpacked AGFL formats without a filesystem crash.

Suggested-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by Dave Chiluk <chiluk+linuxxfs@indeed.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-03-23 18:05:06 -07:00
Christoph Hellwig 3e4da466bf xfs: unwind the try_again loop in xfs_log_force
Instead split out a __xfs_log_fore_lsn helper that gets called again
with the already_slept flag set to true in case we had to sleep.

This prepares for aio_fsync support.

Signed-off-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>
2018-03-23 18:05:06 -07:00
Christoph Hellwig 93806299b5 xfs: refactor xfs_log_force_lsn
Use the the smallest possible loop as preable to find the correct iclog
buffer, and then use gotos for unwinding to straighten the code.

Also fix the top of function comment while we're at it.

Signed-off-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>
2018-03-23 18:05:06 -07:00
Ingo Molnar 793057e1c7 vfs: Replace stray non-ASCII homoglyph characters with their ASCII equivalents
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-03-19 01:07:42 -04:00
Christoph Hellwig df79b81b2e xfs: minor cleanup for xfs_reflink_end_cow
Use xfs_iext_prev_extent to skip to the previous extent instead of
opencoding it.

Signed-off-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>
2018-03-15 10:31:38 -07:00
Christoph Hellwig 1d4352de51 xfs: minor cleanup for xfs_get_blocks
Simplify the control flow a bit in preparation for O_ATOMIC-related
changes.

Signed-off-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>
2018-03-15 10:31:38 -07:00
Christoph Hellwig f5c54717bf xfs: remove xfs_zero_range
This helper doesn't add any real value over just calling iomap_zero_range
directly, so remove it.

Signed-off-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>
2018-03-15 10:31:38 -07:00
Christoph Hellwig c7dbe3f2c4 xfs: assert that xfs_reflink_allocate_cow is called with XFS_ILOCK_EXCL
Now that we convert COW preallocations from unwritten to real on every
call this function needs to be called with the ilock held exclusively.

Fortunately we already do that, but update the assert to match.

Signed-off-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>
2018-03-15 10:31:38 -07:00
Christoph Hellwig 7d9df3c163 xfs: don't use XFS_BMAPI_ENTRIRE in xfs_get_blocks
There is no reason to get a mapping bigger than what we were asked for.

Signed-off-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>
2018-03-15 10:31:38 -07:00
Christoph Hellwig 5bcffe300c xfs: fix the check for COW extents in xfs_swap_extents
i_cnextents does not include delayed allocated extents, so switch
to the inode fork size check that we already use in other places
instead.

Signed-off-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>
2018-03-15 10:31:38 -07:00
Christoph Hellwig e6b9657056 xfs: refactor xfs_log_force
Streamline the conditionals so that it is more obvious which specific case
form the top of the function comments is being handled.  Use gotos only
for early returns.

Signed-off-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>
2018-03-14 11:12:52 -07:00
Christoph Hellwig 656de4ffaf xfs: merge _xfs_log_force_lsn and xfs_log_force_lsn
Switch to a single interface for flushing the log to a specific LSN, which
gives consistent trace point coverage and a less confusing interface.

The was only a single user of the previous xfs_log_force_lsn function,
which now also passes a NULL log_flushed argument.

Signed-off-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>
2018-03-14 11:12:52 -07:00
Christoph Hellwig 60e5bb7844 xfs: merge _xfs_log_force and xfs_log_force
Switch to a single interface for flushing the whole log, which gives
consistent trace point coverage, and removes the unused log_flushed
argument for the previous _xfs_log_force callers.

Signed-off-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>
2018-03-14 11:12:52 -07:00
Christoph Hellwig 2b56c2857f xfs: remove the unused log_flushed variable in xfs_extent_busy_flush
Signed-off-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>
2018-03-14 11:12:52 -07:00
Christoph Hellwig 4f7aa2fd8c xfs: remove an outdated comment for xfs_inode_item_committing
The function now does something, and that something is central to our
inode logging scheme.

Signed-off-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>
2018-03-14 11:12:51 -07:00
Christoph Hellwig 2022ab36fe xfs: remove misleading comment text on xfs_inode_item_unlock
Signed-off-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>
2018-03-14 11:12:51 -07:00
Brian Foster 0ab32086d0 xfs: account only rmapbt-used blocks against rmapbt perag res
The rmapbt perag metadata reservation reserves blocks for the
reverse mapping btree (rmapbt). Since the rmapbt uses blocks from
the agfl and perag accounting is updated as blocks are allocated
from the allocation btrees, the reservation actually accounts blocks
as they are allocated to (or freed from) the agfl rather than the
rmapbt itself.

While this works for blocks that are eventually used for the rmapbt,
not all agfl blocks are destined for the rmapbt. Blocks that are
allocated to the agfl (and thus "reserved" for the rmapbt) but then
used by another structure leads to a growing inconsistency over time
between the runtime tracking of rmapbt usage vs. actual rmapbt
usage. Since the runtime tracking thinks all agfl blocks are rmapbt
blocks, it essentially believes that less future reservation is
required to satisfy the rmapbt than what is actually necessary.

The inconsistency is rectified across mount cycles because the perag
reservation is initialized based on the actual rmapbt usage at mount
time. The problem, however, is that the excessive drain of the
reservation at runtime opens a window to allocate blocks for other
purposes that might be required for the rmapbt on a subsequent
mount. This problem can be demonstrated by a simple test that runs
an allocation workload to consume agfl blocks over time and then
observe the difference in the agfl reservation requirement across an
unmount/mount cycle:

  mount ...: xfs_ag_resv_init: ... resv 3193 ask 3194 len 3194
  ...
  ...      : xfs_ag_resv_alloc_extent: ... resv 2957 ask 3194 len 1
  umount...: xfs_ag_resv_free: ... resv 2956 ask 3194 len 0
  mount ...: xfs_ag_resv_init: ... resv 3052 ask 3194 len 3194

As the above tracepoints show, the reservation requirement reduces
from 3194 blocks to 2956 blocks as the workload runs.  Without any
other changes in the filesystem, the same reservation requirement
jumps from 2956 to 3052 blocks over a umount/mount cycle.

To address this divergence, update the RMAPBT reservation to account
blocks used for the rmapbt only rather than all blocks filled into
the agfl. This patch makes several high-level changes toward that
end:

1.) Reintroduce an AGFL reservation type to serve as an accounting
    no-op for blocks allocated to (or freed from) the AGFL.
2.) Invoke RMAPBT usage accounting from the actual rmapbt block
    allocation path rather than the AGFL allocation path.

The first change is required because agfl blocks are considered free
blocks throughout their lifetime. The perag reservation subsystem is
invoked unconditionally by the allocation subsystem, so we need a
way to tell the perag subsystem (via the allocation subsystem) to
not make any accounting changes for blocks filled into the AGFL.

The second change causes the in-core RMAPBT reservation usage
accounting to remain consistent with the on-disk state at all times
and eliminates the risk of leaving the rmapbt reservation
underfilled.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-03-11 20:27:57 -07:00
Brian Foster 2159286335 xfs: rename agfl perag res type to rmapbt
The AGFL perag reservation type accounts all allocations that feed
into (or are released from) the allocation group free list (agfl).
The purpose of the reservation is to support worst case conditions
for the reverse mapping btree (rmapbt). As such, the agfl
reservation usage accounting only considers rmapbt usage when the
in-core counters are initialized at mount time.

This implementation inconsistency leads to divergence of the in-core
and on-disk usage accounting over time. In preparation to resolve
this inconsistency and adjust the AGFL reservation into an rmapbt
specific reservation, rename the AGFL reservation type and
associated accounting fields to something more rmapbt-specific. Also
fix up a couple tracepoints that incorrectly use the AGFL
reservation type to pass the agfl state of the associated extent
where the raw reservation type is expected.

Note that this patch does not change perag reservation behavior.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-03-11 20:27:57 -07:00
Brian Foster b3fed43482 xfs: account format bouncing into rmapbt swapext tx reservation
The extent swap mechanism requires a unique implementation for
rmapbt enabled filesystems. Because the rmapbt tracks extent owner
information, extent swap must individually unmap and remap each
extent between the two inodes.

The rmapbt extent swap transaction block reservation currently
accounts for the worst case bmapbt block and rmapbt block
consumption based on the extent count of each inode. There is a
corner case that exists due to the extent swap implementation that
is not covered by this reservation, however.

If one of the associated inodes is just over the max extent count
used for extent format inodes (i.e., the inode is in btree format by
a single extent), the unmap/remap cycle of the extent swap can
bounce the inode between extent and btree format multiple times,
almost as many times as there are extents in the inode (if the
opposing inode happens to have one less, for example). Each back and
forth cycle involves a block free and allocation, which isn't a
problem except for that the initial transaction reservation must
account for the total number of block allocations performed by the
chain of deferred operations. If not, a block reservation overrun
occurs and the filesystem shuts down.

Update the rmapbt extent swap block reservation to check for this
situation and add some block reservation slop to ensure the entire
operation succeeds. We'd never likely require reservation for both
inodes as fsr wouldn't defrag the file in that case, but the
additional reservation is constrained by the data fork size so be
cautious and check for both.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-03-11 20:27:57 -07:00