No description
  • C 98.2%
  • Assembly 1%
  • Makefile 0.3%
  • Shell 0.2%
  • Python 0.1%
Find a file
Repository files (latest commit first)
Filename Latest commit message Latest commit date
Filipe Manana 63008dab58 btrfs: fix race between quota disable and relocation
[ Upstream commit 8a4a0b2a3eaf75ca8854f856ef29690c12b2f531 ]

If we disable quotas while we have a relocation of a metadata block group
that has extents belonging to the quota root, we can cause the relocation
to fail with -ENOENT. This is because relocation builds backref nodes for
extents of the quota root and later needs to walk the backrefs and access
the quota root - however if in between a task disables quotas, it results
in deleting the quota root from the root tree (with btrfs_del_root(),
called from btrfs_quota_disable().

This can be sporadically triggered by test case btrfs/255 from fstests:

  $ ./check btrfs/255
  FSTYP         -- btrfs
  PLATFORM      -- Linux/x86_64 debian0 6.4.0-rc6-btrfs-next-134+ #1 SMP PREEMPT_DYNAMIC Thu Jun 15 11:59:28 WEST 2023
  MKFS_OPTIONS  -- /dev/sdc
  MOUNT_OPTIONS -- /dev/sdc /home/fdmanana/btrfs-tests/scratch_1

  btrfs/255 6s ... _check_dmesg: something found in dmesg (see /home/fdmanana/git/hub/xfstests/results//btrfs/255.dmesg)
  - output mismatch (see /home/fdmanana/git/hub/xfstests/results//btrfs/255.out.bad)
#      --- tests/btrfs/255.out	2023-03-02 21:47:53.876609426 +0000
#      +++ /home/fdmanana/git/hub/xfstests/results//btrfs/255.out.bad	2023-06-16 10:20:39.267563212 +0100
#      @@ -1,2 +1,4 @@
#       QA output created by 255
#      +ERROR: error during balancing '/home/fdmanana/btrfs-tests/scratch_1': No such file or directory
#      +There may be more info in syslog - try dmesg | tail
#       Silence is golden
#      ...
      (Run 'diff -u /home/fdmanana/git/hub/xfstests/tests/btrfs/255.out /home/fdmanana/git/hub/xfstests/results//btrfs/255.out.bad'  to see the entire diff)
  Ran: btrfs/255
  Failures: btrfs/255
  Failed 1 of 1 tests

To fix this make the quota disable operation take the cleaner mutex, as
relocation of a block group also takes this mutex. This is also what we
do when deleting a subvolume/snapshot, we take the cleaner mutex in the
cleaner kthread (at cleaner_kthread()) and then we call btrfs_del_root()
at btrfs_drop_snapshot() while under the protection of the cleaner mutex.

Fixes: bed92eae26 ("Btrfs: qgroup implementation and prototypes")
CC: stable@vger.kernel.org # 5.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-11 11:53:44 +02:00
arch x86: fix backwards merge of GDS/SRSO bit 2023-08-08 19:56:37 +02:00
block block/partition: fix signedness issue for Amiga partitions 2023-07-27 08:37:29 +02:00
certs certs/blacklist_hashes.c: fix const confusion in certs blacklist 2022-06-22 14:11:22 +02:00
crypto KEYS: asymmetric: Copy sig and digest in public_key_verify_signature() 2023-06-21 15:44:08 +02:00
Documentation Documentation/x86: Fix backwards on/off logic about YMM support 2023-08-08 19:56:36 +02:00
drivers bcache: Fix __bch_btree_node_alloc to make the failure behavior consistent 2023-08-11 11:53:44 +02:00
fs btrfs: fix race between quota disable and relocation 2023-08-11 11:53:44 +02:00
include jbd2: fix kernel-doc markups 2023-08-11 11:53:43 +02:00
init x86/mm: Initialize text poking earlier 2023-08-08 19:56:36 +02:00
ipc ipc/sem: Fix dangling sem_array access in semtimedop race 2022-12-08 11:23:06 +01:00
kernel mm: Move mm_cachep initialization to mm_init() 2023-08-08 19:56:36 +02:00
lib debugobjects: Recheck debug_objects_enabled before reporting 2023-07-27 08:37:41 +02:00
LICENSES
mm mm: make wait_on_page_writeback() wait for multiple pending writebacks 2023-06-28 10:18:42 +02:00
net tcp: annotate data-races around fastopenq.max_qlen 2023-07-27 08:37:45 +02:00
samples samples/bpf: Fix buffer overflow in tcp_basertt 2023-07-27 08:37:07 +02:00
scripts modpost: fix off by one in is_executable_section() 2023-07-27 08:37:18 +02:00
security integrity: Fix possible multiple allocation in integrity_inode_get() 2023-07-27 08:37:25 +02:00
sound ALSA: jack: Fix mutex call in snd_jack_report() 2023-07-27 08:37:24 +02:00
tools x86/bugs: Increase the x86 bugs vector size to two u32s 2023-08-08 19:56:37 +02:00
usr
virt KVM: Destroy target device if coalesced MMIO unregistration fails 2023-03-11 16:44:01 +01:00
.clang-format
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS Remove DECnet support from kernel 2023-06-21 15:44:10 +02:00
Makefile Linux 5.4.252 2023-08-08 19:56:37 +02:00
README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.