free_device rcu callback, scheduled from btrfs_rm_dev_replace_srcdev,
can be processed before btrfs_scratch_superblock is called, which would
result in a use-after-free on btrfs_device contents. Fix this by
zeroing the superblock before the rcu callback is registered.
Cc: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
The current implementation of worker threads in Btrfs has races in
worker stopping code, which cause all kinds of panics and lockups when
running btrfs/011 xfstest in a loop. The problem is that
btrfs_stop_workers is unsynchronized with respect to check_idle_worker,
check_busy_worker and __btrfs_start_workers.
E.g., check_idle_worker race flow:
btrfs_stop_workers(): check_idle_worker(aworker):
- grabs the lock
- splices the idle list into the
working list
- removes the first worker from the
working list
- releases the lock to wait for
its kthread's completion
- grabs the lock
- if aworker is on the working list,
moves aworker from the working list
to the idle list
- releases the lock
- grabs the lock
- puts the worker
- removes the second worker from the
working list
......
btrfs_stop_workers returns, aworker is on the idle list
FS is umounted, memory is freed
......
aworker is waken up, fireworks ensue
With this applied, I wasn't able to trigger the problem in 48 hours,
whereas previously I could reliably reproduce at least one of these
races within an hour.
Reported-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
The crash[1] is found by xfstests/generic/208 with "-o compress",
it's not reproduced everytime, but it does panic.
The bug is quite interesting, it's actually introduced by a recent commit
(573aecafca,
Btrfs: actually limit the size of delalloc range).
Btrfs implements delay allocation, so during writeback, we
(1) get a page A and lock it
(2) search the state tree for delalloc bytes and lock all pages within the range
(3) process the delalloc range, including find disk space and create
ordered extent and so on.
(4) submit the page A.
It runs well in normal cases, but if we're in a racy case, eg.
buffered compressed writes and aio-dio writes,
sometimes we may fail to lock all pages in the 'delalloc' range,
in which case, we need to fall back to search the state tree again with
a smaller range limit(max_bytes = PAGE_CACHE_SIZE - offset).
The mentioned commit has a side effect, that is, in the fallback case,
we can find delalloc bytes before the index of the page we already have locked,
so we're in the case of (delalloc_end <= *start) and return with (found > 0).
This ends with not locking delalloc pages but making ->writepage still
process them, and the crash happens.
This fixes it by just thinking that we find nothing and returning to caller
as the caller knows how to deal with it properly.
[1]:
------------[ cut here ]------------
kernel BUG at mm/page-writeback.c:2170!
[...]
CPU: 2 PID: 11755 Comm: btrfs-delalloc- Tainted: G O 3.11.0+ #8
[...]
RIP: 0010:[<ffffffff810f5093>] [<ffffffff810f5093>] clear_page_dirty_for_io+0x1e/0x83
[...]
[ 4934.248731] Stack:
[ 4934.248731] ffff8801477e5dc8 ffffea00049b9f00 ffff8801869f9ce8 ffffffffa02b841a
[ 4934.248731] 0000000000000000 0000000000000000 0000000000000fff 0000000000000620
[ 4934.248731] ffff88018db59c78 ffffea0005da8d40 ffffffffa02ff860 00000001810016c0
[ 4934.248731] Call Trace:
[ 4934.248731] [<ffffffffa02b841a>] extent_range_clear_dirty_for_io+0xcf/0xf5 [btrfs]
[ 4934.248731] [<ffffffffa02a8889>] compress_file_range+0x1dc/0x4cb [btrfs]
[ 4934.248731] [<ffffffff8104f7af>] ? detach_if_pending+0x22/0x4b
[ 4934.248731] [<ffffffffa02a8bad>] async_cow_start+0x35/0x53 [btrfs]
[ 4934.248731] [<ffffffffa02c694b>] worker_loop+0x14b/0x48c [btrfs]
[ 4934.248731] [<ffffffffa02c6800>] ? btrfs_queue_worker+0x25c/0x25c [btrfs]
[ 4934.248731] [<ffffffff810608f5>] kthread+0x8d/0x95
[ 4934.248731] [<ffffffff81060868>] ? kthread_freezable_should_stop+0x43/0x43
[ 4934.248731] [<ffffffff814fe09c>] ret_from_fork+0x7c/0xb0
[ 4934.248731] [<ffffffff81060868>] ? kthread_freezable_should_stop+0x43/0x43
[ 4934.248731] Code: ff 85 c0 0f 94 c0 0f b6 c0 59 5b 5d c3 0f 1f 44 00 00 55 48 89 e5 41 54 53 48 89 fb e8 2c de 00 00 49 89 c4 48 8b 03 a8 01 75 02 <0f> 0b 4d 85 e4 74 52 49 8b 84 24 80 00 00 00 f6 40 20 01 75 44
[ 4934.248731] RIP [<ffffffff810f5093>] clear_page_dirty_for_io+0x1e/0x83
[ 4934.248731] RSP <ffff8801869f9c48>
[ 4934.280307] ---[ end trace 36f06d3f8750236a ]---
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
If we crash with a log, remount and recover that log, and then crash before we
can commit another transaction we will get transid verify errors on the next
mount. This is because we were not zero'ing out the log when we committed the
transaction after recovery. This is ok as long as we commit another transaction
at some point in the future, but if you abort or something else goes wrong you
can end up in this weird state because the recovery stuff says that the tree log
should have a generation+1 of the super generation, which won't be the case of
the transaction that was started for recovery. Fix this by removing the check
and _always_ zero out the log portion of the super when we commit a transaction.
This fixes the transid verify issues I was seeing with my force errors tests.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Pull xfs bugfixes from Ben Myers:
- fix for directory node collapse regression
- fix for recovery over stale on disk structures
- fix for eofblocks ioctl
- fix asserts in xfs_inode_free
- lock the ail before removing an item from it
* tag 'xfs-for-linus-v3.12-rc3' of git://oss.sgi.com/xfs/xfs:
xfs: fix node forward in xfs_node_toosmall
xfs: log recovery lsn ordering needs uuid check
xfs: fix XFS_IOC_FREE_EOFBLOCKS definition
xfs: asserting lock not held during freeing not valid
xfs: lock the AIL before removing the buffer item
Pull reiserfs and UDF fixes from Jan Kara:
"The contains fix of an UDF oops when mounting corrupted media and a
fix of a race in reiserfs leading to oops"
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
reiserfs: fix race with flush_used_journal_lists and flush_journal_list
reiserfs: remove useless flush_old_journal_lists
udf: Fortify LVID loading
Commit f5ea1100 cleans up the disk to host conversions for
node directory entries, but because a variable is reused in
xfs_node_toosmall() the next node is not correctly found.
If the original node is small enough (<= 3/8 of the node size),
this change may incorrectly cause a node collapse when it should
not. That will cause an assert in xfstest generic/319:
Assertion failed: first <= last && last < BBTOB(bp->b_length),
file: /root/newest/xfs/fs/xfs/xfs_trans_buf.c, line: 569
Keep the original node header to get the correct forward node.
(When a node is considered for a merge with a sibling, it overwrites the
sibling pointers of the original incore nodehdr with the sibling's
pointers. This leads to loop considering the original node as a merge
candidate with itself in the second pass, and so it incorrectly
determines a merge should occur.)
Signed-off-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
[v3: added Dave Chinner's (slightly modified) suggestion to the commit header,
cleaned up whitespace. -bpm]
Merge fixes from Andrew Morton:
"Bunch of fixes.
And a reversion of mhocko's "Soft limit rework" patch series. This is
actually your fault for opening the merge window when I was off racing ;)
I didn't read the email thread before sending everything off.
Johannes Weiner raised significant issues:
http://www.spinics.net/lists/cgroups/msg08813.html
and we agreed to back it all out"
I clearly need to be more aware of Andrew's racing schedule.
* akpm:
MAINTAINERS: update mach-bcm related email address
checkpatch: make extern in .h prototypes quieter
cciss: fix info leak in cciss_ioctl32_passthru()
cpqarray: fix info leak in ida_locked_ioctl()
kernel/reboot.c: re-enable the function of variable reboot_default
audit: fix endless wait in audit_log_start()
revert "memcg, vmscan: integrate soft reclaim tighter with zone shrinking code"
revert "memcg: get rid of soft-limit tree infrastructure"
revert "vmscan, memcg: do softlimit reclaim also for targeted reclaim"
revert "memcg: enhance memcg iterator to support predicates"
revert "memcg: track children in soft limit excess to improve soft limit"
revert "memcg, vmscan: do not attempt soft limit reclaim if it would not scan anything"
revert "memcg: track all children over limit in the root"
revert "memcg, vmscan: do not fall into reclaim-all pass too quickly"
fs/ocfs2/super.c: use a bigger nodestr in ocfs2_dismount_volume
watchdog: update watchdog_thresh properly
watchdog: update watchdog attributes atomically
While printing 32-bit node numbers, an 8-byte string is not enough.
Increase the size of the string to 12 chars.
This got left out in commit 49fa8140e4 ("fs/ocfs2/super.c: Use bigger
nodestr to accomodate 32-bit node numbers").
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After a fair number of xfstests runs, xfs/182 started to fail
regularly with a corrupted directory - a directory read verifier was
failing after recovery because it found a block with a XARM magic
number (remote attribute block) rather than a directory data block.
The first time I saw this repeated failure I did /something/ and the
problem went away, so I was never able to find the underlying
problem. Test xfs/182 failed again today, and I found the root
cause before I did /something else/ that made it go away.
Tracing indicated that the block in question was being correctly
logged, the log was being flushed by sync, but the buffer was not
being written back before the shutdown occurred. Tracing also
indicated that log recovery was also reading the block, but then
never writing it before log recovery invalidated the cache,
indicating that it was not modified by log recovery.
More detailed analysis of the corpse indicated that the filesystem
had a uuid of "a4131074-1872-4cac-9323-2229adbcb886" but the XARM
block had a uuid of "8f32f043-c3c9-e7f8-f947-4e7f989c05d3", which
indicated it was a block from an older filesystem. The reason that
log recovery didn't replay it was that the LSN in the XARM block was
larger than the LSN of the transaction being replayed, and so the
block was not overwritten by log recovery.
Hence, log recovery cant blindly trust the magic number and LSN in
the block - it must verify that it belongs to the filesystem being
recovered before using the LSN. i.e. if the UUIDs don't match, we
need to unconditionally recovery the change held in the log.
This patch was first tested on a block device that was repeatedly
causing xfs/182 to fail with the same failure on the same block with
the same directory read corruption signature (i.e. XARM block). It
did not fail, and hasn't failed since.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
It uses a kernel internal structure in it's definition rather than
the user visible structure that is passed to the ioctl.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
When we free an inode, we do so via RCU. As an RCU lookup can occur
at any time before we free an inode, and that lookup takes the inode
flags lock, we cannot safely assert that the flags lock is not held
just before marking it dead and running call_rcu() to free the
inode.
We check on allocation of a new inode structre that the lock is not
held, so we still have protection against locks being leaked and
hence not correctly initialised when allocated out of the slab.
Hence just remove the assert...
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Regression introduced by commit 46f9d2e ("xfs: aborted buf items can
be in the AIL") which fails to lock the AIL before removing the
item. Spinlock debugging throws a warning about this.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
There are two locks involved in managing the journal lists. The general
reiserfs_write_lock and the journal->j_flush_mutex.
While flush_journal_list is sleeping to acquire the j_flush_mutex or to
submit a block for write, it will drop the write lock. This allows
another thread to acquire the write lock and ultimately call
flush_used_journal_lists to traverse the list of journal lists and
select one for flushing. It can select the journal_list that has just
had flush_journal_list called on it in the original thread and call it
again with the same journal_list.
The second thread then drops the write lock to acquire j_flush_mutex and
the first thread reacquires it and continues execution and eventually
clears and frees the journal list before dropping j_flush_mutex and
returning.
The second thread acquires j_flush_mutex and ends up operating on a
journal_list that has already been released. If the memory hasn't
been reused, we'll soon after hit a BUG_ON because the transaction id
has already been cleared. If it's been reused, we'll crash in other
fun ways.
Since flush_journal_list will synchronize on j_flush_mutex, we can fix
the race by taking a proper reference in flush_used_journal_lists
and checking to see if it's still valid after the mutex is taken. It's
safe to iterate the list of journal lists and pick a list with
just the write lock as long as a reference is taken on the journal list
before we drop the lock. We already have code to handle whether a
transaction has been flushed already so we can use that to handle the
race and get rid of the trans_id BUG_ON.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Commit a3172027 introduced test_transaction as a requirement for
flushing old lists -- but it can never return 1 unless the transaction
has already been flushed.
As a result, we have a routine that iterates the j_realblocks list but
doesn't actually do anything. Since it's been this way since 2006 and
the latency numbers were what Chris expected, let's just rip it out.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Jan Kara <jack@suse.cz>
A user has reported an oops in udf_statfs() that was caused by
numOfPartitions entry in LVID structure being corrupted. Fix the problem
by verifying whether numOfPartitions makes sense at least to the extent
that LVID fits into a single block as it should.
Reported-by: Juergen Weigert <jw@suse.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Pull block IO fixes from Jens Axboe:
"After merge window, no new stuff this time only a collection of neatly
confined and simple fixes"
* 'for-3.12/core' of git://git.kernel.dk/linux-block:
cfq: explicitly use 64bit divide operation for 64bit arguments
block: Add nr_bios to block_rq_remap tracepoint
If the queue is dying then we only call the rq->end_io callout. This leaves bios setup on the request, because the caller assumes when the blk_execute_rq_nowait/blk_execute_rq call has completed that the rq->bios have been cleaned up.
bio-integrity: Fix use of bs->bio_integrity_pool after free
blkcg: relocate root_blkg setting and clearing
block: Convert kmalloc_node(...GFP_ZERO...) to kzalloc_node(...)
block: trace all devices plug operation
Pull btrfs fixes from Chris Mason:
"These are mostly bug fixes and a two small performance fixes. The
most important of the bunch are Josef's fix for a snapshotting
regression and Mark's update to fix compile problems on arm"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (25 commits)
Btrfs: create the uuid tree on remount rw
btrfs: change extent-same to copy entire argument struct
Btrfs: dir_inode_operations should use btrfs_update_time also
btrfs: Add btrfs: prefix to kernel log output
btrfs: refuse to remount read-write after abort
Btrfs: btrfs_ioctl_default_subvol: Revert back to toplevel subvolume when arg is 0
Btrfs: don't leak transaction in btrfs_sync_file()
Btrfs: add the missing mutex unlock in write_all_supers()
Btrfs: iput inode on allocation failure
Btrfs: remove space_info->reservation_progress
Btrfs: kill delay_iput arg to the wait_ordered functions
Btrfs: fix worst case calculator for space usage
Revert "Btrfs: rework the overcommit logic to be based on the total size"
Btrfs: improve replacing nocow extents
Btrfs: drop dir i_size when adding new names on replay
Btrfs: replay dir_index items before other items
Btrfs: check roots last log commit when checking if an inode has been logged
Btrfs: actually log directory we are fsync()'ing
Btrfs: actually limit the size of delalloc range
Btrfs: allocate the free space by the existed max extent size when ENOSPC
...
Users have been complaining of the uuid tree stuff warning that there is no uuid
root when trying to do snapshot operations. This is because if you mount -o ro
we will not create the uuid tree. But then if you mount -o rw,remount we will
still not create it and then any subsequent snapshot/subvol operations you try
to do will fail gloriously. Fix this by creating the uuid_root on remount rw if
it was not already there. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
btrfs_ioctl_file_extent_same() uses __put_user_unaligned() to copy some data
back to it's argument struct. Unfortunately, not all architectures provide
__put_user_unaligned(), so compiles break on them if btrfs is selected.
Instead, just copy the whole struct in / out at the start and end of
operations, respectively.
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Commit 2bc5565286 (Btrfs: don't update atime on
RO subvolumes) ensures that the access time of an inode is not updated when
the inode lives in a read-only subvolume.
However, if a directory on a read-only subvolume is accessed, the atime is
updated. This results in a write operation to a read-only subvolume. I
believe that access times should never be updated on read-only subvolumes.
To reproduce:
# mkfs.btrfs -f /dev/dm-3
(...)
# mount /dev/dm-3 /mnt
# btrfs subvol create /mnt/sub
Create subvolume '/mnt/sub'
# mkdir /mnt/sub/dir
# echo "abc" > /mnt/sub/dir/file
# btrfs subvol snapshot -r /mnt/sub /mnt/rosnap
Create a readonly snapshot of '/mnt/sub' in '/mnt/rosnap'
# stat /mnt/rosnap/dir
File: `/mnt/rosnap/dir'
Size: 8 Blocks: 0 IO Block: 4096 directory
Device: 16h/22d Inode: 257 Links: 1
Access: (0755/drwxr-xr-x) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2013-09-11 07:21:49.389157126 -0400
Modify: 2013-09-11 07:22:02.330156079 -0400
Change: 2013-09-11 07:22:02.330156079 -0400
# ls /mnt/rosnap/dir
file
# stat /mnt/rosnap/dir
File: `/mnt/rosnap/dir'
Size: 8 Blocks: 0 IO Block: 4096 directory
Device: 16h/22d Inode: 257 Links: 1
Access: (0755/drwxr-xr-x) Uid: ( 0/ root) Gid: ( 0/ root)
Access: 2013-09-11 07:22:56.797151670 -0400
Modify: 2013-09-11 07:22:02.330156079 -0400
Change: 2013-09-11 07:22:02.330156079 -0400
Reported-by: Koen De Wit <koen.de.wit@oracle.com>
Signed-off-by: Guangyu Sun <guangyu.sun@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
The kernel log entries for device label %s and device fsid %pU
are missing the btrfs: prefix. Add those here.
Signed-off-by: Frank Holton <fholton@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Darrick J. Wong
Chris Mason
Ilya Dryomov
Liu Bo
Josef Bacik
Linus Torvalds
Mark Tinguely
Goldwyn Rodrigues
Kent Overstreet
Dave Chinner
Jeff Mahoney
Jan Kara
Mark Fasheh
Guangyu Sun
Frank Holton