<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/fs/btrfs/tree-log.c, branch master</title>
<subtitle>Hosts the 0x221E linux distro kernel.</subtitle>
<id>https://universe.0xinfinity.dev/distro/kernel/atom?h=master</id>
<link rel='self' href='https://universe.0xinfinity.dev/distro/kernel/atom?h=master'/>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/'/>
<updated>2026-03-16T15:53:06Z</updated>
<entry>
<title>Merge tag 'for-7.0-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux</title>
<updated>2026-03-16T15:53:06Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2026-03-16T15:53:06Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=2d1373e4246da3b58e1df058374ed6b101804e07'/>
<id>urn:sha1:2d1373e4246da3b58e1df058374ed6b101804e07</id>
<content type='text'>
Pull btrfs fixes from David Sterba:

 - fix logging of new dentries when logging parent directory and there
   are conflicting inodes (e.g. deleted directory)

 - avoid taking big device lock for zone setup, this is not necessary
   during mount

 - tune message verbosity when auto-reclaiming zones when low on space

 - fix slightly misleading message of root item check

* tag 'for-7.0-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: tree-checker: fix misleading root drop_level error message
  btrfs: log new dentries when logging parent dir of a conflicting inode
  btrfs: don't take device_list_mutex when querying zone info
  btrfs: pass 'verbose' parameter to btrfs_relocate_block_group
</content>
</entry>
<entry>
<title>btrfs: log new dentries when logging parent dir of a conflicting inode</title>
<updated>2026-03-13T11:48:59Z</updated>
<author>
<name>Filipe Manana</name>
<email>fdmanana@suse.com</email>
</author>
<published>2026-03-03T16:57:43Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=9573a365ff9ff45da9222d3fe63695ce562beb24'/>
<id>urn:sha1:9573a365ff9ff45da9222d3fe63695ce562beb24</id>
<content type='text'>
If we log the parent directory of a conflicting inode, we are not logging
the new dentries of the directory, so when we finish we have the parent
directory's inode marked as logged but we did not log its new dentries.
As a consequence if the parent directory is explicitly fsynced later and
it does not have any new changes since we logged it, the fsync is a no-op
and after a power failure the new dentries are missing.

Example scenario:

  $ mkdir foo

  $ sync

  $rmdir foo

  $ mkdir dir1
  $ mkdir dir2

  # A file with the same name and parent as the directory we just deleted
  # and was persisted in a past transaction. So the deleted directory's
  # inode is a conflicting inode of this new file's inode.
  $ touch foo

  $ ln foo dir2/link

  # The fsync on dir2 will log the parent directory (".") because the
  # conflicting inode (deleted directory) does not exists anymore, but it
  # it does not log its new dentries (dir1).
  $ xfs_io -c "fsync" dir2

  # This fsync on the parent directory is no-op, since the previous fsync
  # logged it (but without logging its new dentries).
  $ xfs_io -c "fsync" .

  &lt;power failure&gt;

  # After log replay dir1 is missing.

Fix this by ensuring we log new dir dentries whenever we log the parent
directory of a no longer existing conflicting inode.

A test case for fstests will follow soon.

Reported-by: Vyacheslav Kovalevsky &lt;slava.kovalevskiy.2014@gmail.com&gt;
Link: https://lore.kernel.org/linux-btrfs/182055fa-e9ce-4089-9f5f-4b8a23e8dd91@gmail.com/
Fixes: a3baaf0d786e ("Btrfs: fix fsync after succession of renames and unlink/rmdir")
Reviewed-by: Boris Burkov &lt;boris@bur.io&gt;
Signed-off-by: Filipe Manana &lt;fdmanana@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>treewide: Replace kmalloc with kmalloc_obj for non-scalar types</title>
<updated>2026-02-21T09:02:28Z</updated>
<author>
<name>Kees Cook</name>
<email>kees@kernel.org</email>
</author>
<published>2026-02-21T07:49:23Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=69050f8d6d075dc01af7a5f2f550a8067510366f'/>
<id>urn:sha1:69050f8d6d075dc01af7a5f2f550a8067510366f</id>
<content type='text'>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook &lt;kees@kernel.org&gt;
</content>
</entry>
<entry>
<title>btrfs: use the btrfs_extent_map_end() helper everywhere</title>
<updated>2026-02-03T06:54:36Z</updated>
<author>
<name>Filipe Manana</name>
<email>fdmanana@suse.com</email>
</author>
<published>2026-01-16T10:57:00Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=ea7ab405c55b6ac4b5c3e61ef37cf697067e3c71'/>
<id>urn:sha1:ea7ab405c55b6ac4b5c3e61ef37cf697067e3c71</id>
<content type='text'>
We have a helper to calculate an extent map's exclusive end offset, but
we only use it in some places. Update every site that open codes the
calculation to use the helper.

Reviewed-by: Johannes Thumshirn &lt;johannes.thumshirn@wdc.com&gt;
Reviewed-by: Qu Wenruo &lt;wqu@suse.com&gt;
Signed-off-by: Filipe Manana &lt;fdmanana@suse.com&gt;
Reviewed-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>btrfs: fix Wmaybe-uninitialized warning in replay_one_buffer()</title>
<updated>2026-01-20T00:41:47Z</updated>
<author>
<name>Qiang Ma</name>
<email>maqianga@uniontech.com</email>
</author>
<published>2025-12-18T08:16:18Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=9c7e71c97c8cd086b148d0d3d1cd84a1deab023c'/>
<id>urn:sha1:9c7e71c97c8cd086b148d0d3d1cd84a1deab023c</id>
<content type='text'>
Warning was found when compiling using loongarch64-gcc 12.3.1:

  $ make CFLAGS_tree-log.o=-Wmaybe-uninitialized

  In file included from fs/btrfs/ctree.h:21,
		   from fs/btrfs/tree-log.c:12:
  fs/btrfs/accessors.h: In function 'replay_one_buffer':
  fs/btrfs/accessors.h:66:16: warning: 'inode_item' may be used uninitialized [-Wmaybe-uninitialized]
     66 |         return btrfs_get_##bits(eb, s, offsetof(type, member));         \
	|                ^~~~~~~~~~
  fs/btrfs/tree-log.c:2803:42: note: 'inode_item' declared here
   2803 |                 struct btrfs_inode_item *inode_item;
	|                                          ^~~~~~~~~~

Initialize the inode_item to NULL, the compiler does not seem to see the
relation between the first 'wc-&gt;log_key.type == BTRFS_INODE_ITEM_KEY'
check and the other one that also checks the replay phase.

Signed-off-by: Qiang Ma &lt;maqianga@uniontech.com&gt;
Reviewed-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>btrfs: fix NULL pointer dereference in do_abort_log_replay()</title>
<updated>2026-01-06T00:23:00Z</updated>
<author>
<name>Suchit Karunakaran</name>
<email>suchitkarunakaran@gmail.com</email>
</author>
<published>2025-12-19T17:14:34Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=530e3d4af566ca44807d79359b90794dea24c4f3'/>
<id>urn:sha1:530e3d4af566ca44807d79359b90794dea24c4f3</id>
<content type='text'>
Coverity reported a NULL pointer dereference issue (CID 1666756) in
do_abort_log_replay(). When btrfs_alloc_path() fails in
replay_one_buffer(), wc-&gt;subvol_path is NULL, but btrfs_abort_log_replay()
calls do_abort_log_replay() which unconditionally dereferences
wc-&gt;subvol_path when attempting to print debug information. Fix this by
adding a NULL check before dereferencing wc-&gt;subvol_path in
do_abort_log_replay().

Fixes: 2753e4917624 ("btrfs: dump detailed info and specific messages on log replay failures")
Reviewed-by: Filipe Manana &lt;fdmanana@suse.com&gt;
Signed-off-by: Suchit Karunakaran &lt;suchitkarunakaran@gmail.com&gt;
Signed-off-by: Filipe Manana &lt;fdmanana@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>btrfs: always detect conflicting inodes when logging inode refs</title>
<updated>2025-12-16T21:53:15Z</updated>
<author>
<name>Filipe Manana</name>
<email>fdmanana@suse.com</email>
</author>
<published>2025-12-11T15:06:26Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=7ba0b6461bc4edb3005ea6e00cdae189bcf908a5'/>
<id>urn:sha1:7ba0b6461bc4edb3005ea6e00cdae189bcf908a5</id>
<content type='text'>
After rename exchanging (either with the rename exchange operation or
regular renames in multiple non-atomic steps) two inodes and at least
one of them is a directory, we can end up with a log tree that contains
only of the inodes and after a power failure that can result in an attempt
to delete the other inode when it should not because it was not deleted
before the power failure. In some case that delete attempt fails when
the target inode is a directory that contains a subvolume inside it, since
the log replay code is not prepared to deal with directory entries that
point to root items (only inode items).

1) We have directories "dir1" (inode A) and "dir2" (inode B) under the
   same parent directory;

2) We have a file (inode C) under directory "dir1" (inode A);

3) We have a subvolume inside directory "dir2" (inode B);

4) All these inodes were persisted in a past transaction and we are
   currently at transaction N;

5) We rename the file (inode C), so at btrfs_log_new_name() we update
   inode C's last_unlink_trans to N;

6) We get a rename exchange for "dir1" (inode A) and "dir2" (inode B),
   so after the exchange "dir1" is inode B and "dir2" is inode A.
   During the rename exchange we call btrfs_log_new_name() for inodes
   A and B, but because they are directories, we don't update their
   last_unlink_trans to N;

7) An fsync against the file (inode C) is done, and because its inode
   has a last_unlink_trans with a value of N we log its parent directory
   (inode A) (through btrfs_log_all_parents(), called from
   btrfs_log_inode_parent()).

8) So we end up with inode B not logged, which now has the old name
   of inode A. At copy_inode_items_to_log(), when logging inode A, we
   did not check if we had any conflicting inode to log because inode
   A has a generation lower than the current transaction (created in
   a past transaction);

9) After a power failure, when replaying the log tree, since we find that
   inode A has a new name that conflicts with the name of inode B in the
   fs tree, we attempt to delete inode B... this is wrong since that
   directory was never deleted before the power failure, and because there
   is a subvolume inside that directory, attempting to delete it will fail
   since replay_dir_deletes() and btrfs_unlink_inode() are not prepared
   to deal with dir items that point to roots instead of inodes.

   When that happens the mount fails and we get a stack trace like the
   following:

   [87.2314] BTRFS info (device dm-0): start tree-log replay
   [87.2318] BTRFS critical (device dm-0): failed to delete reference to subvol, root 5 inode 256 parent 259
   [87.2332] ------------[ cut here ]------------
   [87.2338] BTRFS: Transaction aborted (error -2)
   [87.2346] WARNING: CPU: 1 PID: 638968 at fs/btrfs/inode.c:4345 __btrfs_unlink_inode+0x416/0x440 [btrfs]
   [87.2368] Modules linked in: btrfs loop dm_thin_pool (...)
   [87.2470] CPU: 1 UID: 0 PID: 638968 Comm: mount Tainted: G        W           6.18.0-rc7-btrfs-next-218+ #2 PREEMPT(full)
   [87.2489] Tainted: [W]=WARN
   [87.2494] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014
   [87.2514] RIP: 0010:__btrfs_unlink_inode+0x416/0x440 [btrfs]
   [87.2538] Code: c0 89 04 24 (...)
   [87.2568] RSP: 0018:ffffc0e741f4b9b8 EFLAGS: 00010286
   [87.2574] RAX: 0000000000000000 RBX: ffff9d3ec8a6cf60 RCX: 0000000000000000
   [87.2582] RDX: 0000000000000002 RSI: ffffffff84ab45a1 RDI: 00000000ffffffff
   [87.2591] RBP: ffff9d3ec8a6ef20 R08: 0000000000000000 R09: ffffc0e741f4b840
   [87.2599] R10: ffff9d45dc1fffa8 R11: 0000000000000003 R12: ffff9d3ee26d77e0
   [87.2608] R13: ffffc0e741f4ba98 R14: ffff9d4458040800 R15: ffff9d44b6b7ca10
   [87.2618] FS:  00007f7b9603a840(0000) GS:ffff9d4658982000(0000) knlGS:0000000000000000
   [87.2629] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
   [87.2637] CR2: 00007ffc9ec33b98 CR3: 000000011273e003 CR4: 0000000000370ef0
   [87.2648] Call Trace:
   [87.2651]  &lt;TASK&gt;
   [87.2654]  btrfs_unlink_inode+0x15/0x40 [btrfs]
   [87.2661]  unlink_inode_for_log_replay+0x27/0xf0 [btrfs]
   [87.2669]  check_item_in_log+0x1ea/0x2c0 [btrfs]
   [87.2676]  replay_dir_deletes+0x16b/0x380 [btrfs]
   [87.2684]  fixup_inode_link_count+0x34b/0x370 [btrfs]
   [87.2696]  fixup_inode_link_counts+0x41/0x160 [btrfs]
   [87.2703]  btrfs_recover_log_trees+0x1ff/0x7c0 [btrfs]
   [87.2711]  ? __pfx_replay_one_buffer+0x10/0x10 [btrfs]
   [87.2719]  open_ctree+0x10bb/0x15f0 [btrfs]
   [87.2726]  btrfs_get_tree.cold+0xb/0x16c [btrfs]
   [87.2734]  ? fscontext_read+0x15c/0x180
   [87.2740]  ? rw_verify_area+0x50/0x180
   [87.2746]  vfs_get_tree+0x25/0xd0
   [87.2750]  vfs_cmd_create+0x59/0xe0
   [87.2755]  __do_sys_fsconfig+0x4f6/0x6b0
   [87.2760]  do_syscall_64+0x50/0x1220
   [87.2764]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
   [87.2770] RIP: 0033:0x7f7b9625f4aa
   [87.2775] Code: 73 01 c3 48 (...)
   [87.2803] RSP: 002b:00007ffc9ec35b08 EFLAGS: 00000246 ORIG_RAX: 00000000000001af
   [87.2817] RAX: ffffffffffffffda RBX: 0000558bfa91ac20 RCX: 00007f7b9625f4aa
   [87.2829] RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000003
   [87.2842] RBP: 0000558bfa91b120 R08: 0000000000000000 R09: 0000000000000000
   [87.2854] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
   [87.2864] R13: 00007f7b963f1580 R14: 00007f7b963f326c R15: 00007f7b963d8a23
   [87.2877]  &lt;/TASK&gt;
   [87.2882] ---[ end trace 0000000000000000 ]---
   [87.2891] BTRFS: error (device dm-0 state A) in __btrfs_unlink_inode:4345: errno=-2 No such entry
   [87.2904] BTRFS: error (device dm-0 state EAO) in do_abort_log_replay:191: errno=-2 No such entry
   [87.2915] BTRFS critical (device dm-0 state EAO): log tree (for root 5) leaf currently being processed (slot 7 key (258 12 257)):
   [87.2929] BTRFS info (device dm-0 state EAO): leaf 30736384 gen 10 total ptrs 7 free space 15712 owner 18446744073709551610
   [87.2929] BTRFS info (device dm-0 state EAO): refs 3 lock_owner 0 current 638968
   [87.2929]      item 0 key (257 INODE_ITEM 0) itemoff 16123 itemsize 160
   [87.2929]              inode generation 9 transid 10 size 0 nbytes 0
   [87.2929]              block group 0 mode 40755 links 1 uid 0 gid 0
   [87.2929]              rdev 0 sequence 7 flags 0x0
   [87.2929]              atime 1765464494.678070921
   [87.2929]              ctime 1765464494.686606513
   [87.2929]              mtime 1765464494.686606513
   [87.2929]              otime 1765464494.678070921
   [87.2929]      item 1 key (257 INODE_REF 256) itemoff 16109 itemsize 14
   [87.2929]              index 4 name_len 4
   [87.2929]      item 2 key (257 DIR_LOG_INDEX 2) itemoff 16101 itemsize 8
   [87.2929]              dir log end 2
   [87.2929]      item 3 key (257 DIR_LOG_INDEX 3) itemoff 16093 itemsize 8
   [87.2929]              dir log end 18446744073709551615
   [87.2930]      item 4 key (257 DIR_INDEX 3) itemoff 16060 itemsize 33
   [87.2930]              location key (258 1 0) type 1
   [87.2930]              transid 10 data_len 0 name_len 3
   [87.2930]      item 5 key (258 INODE_ITEM 0) itemoff 15900 itemsize 160
   [87.2930]              inode generation 9 transid 10 size 0 nbytes 0
   [87.2930]              block group 0 mode 100644 links 1 uid 0 gid 0
   [87.2930]              rdev 0 sequence 2 flags 0x0
   [87.2930]              atime 1765464494.678456467
   [87.2930]              ctime 1765464494.686606513
   [87.2930]              mtime 1765464494.678456467
   [87.2930]              otime 1765464494.678456467
   [87.2930]      item 6 key (258 INODE_REF 257) itemoff 15887 itemsize 13
   [87.2930]              index 3 name_len 3
   [87.2930] BTRFS critical (device dm-0 state EAO): log replay failed in unlink_inode_for_log_replay:1045 for root 5, stage 3, with error -2: failed to unlink inode 256 parent dir 259 name subvol root 5
   [87.2963] BTRFS: error (device dm-0 state EAO) in btrfs_recover_log_trees:7743: errno=-2 No such entry
   [87.2981] BTRFS: error (device dm-0 state EAO) in btrfs_replay_log:2083: errno=-2 No such entry (Failed to recover log tr

So fix this by changing copy_inode_items_to_log() to always detect if
there are conflicting inodes for the ref/extref of the inode being logged
even if the inode was created in a past transaction.

A test case for fstests will follow soon.

CC: stable@vger.kernel.org # 6.1+
Signed-off-by: Filipe Manana &lt;fdmanana@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>btrfs: do not skip logging new dentries when logging a new name</title>
<updated>2025-12-08T20:46:56Z</updated>
<author>
<name>Filipe Manana</name>
<email>fdmanana@suse.com</email>
</author>
<published>2025-12-03T17:02:00Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=5630f7557de61264ccb4f031d4734a1a97eaed16'/>
<id>urn:sha1:5630f7557de61264ccb4f031d4734a1a97eaed16</id>
<content type='text'>
When we are logging a directory and the log context indicates that we
are logging a new name for some other file (that is or was inside that
directory), we skip logging the inodes for new dentries in the directory.

This is ok most of the time, but if after the rename or link operation
that triggered the logging of that directory, we have an explicit fsync
of that directory without the directory inode being evicted and reloaded,
we end up never logging the inodes for the new dentries that we found
during the new name logging, as the next directory fsync will only process
dentries that were added after the last time we logged the directory (we
are doing an incremental directory logging).

So make sure we always log new dentries for a directory even if we are
in a context of logging a new name.

We started skipping logging inodes for new dentries as of commit
c48792c6ee7a ("btrfs: do not log new dentries when logging that a new name
exists") and it was fine back then, because when logging a directory we
always iterated over all the directory entries (for leaves changed in the
current transaction) so a subsequent fsync would always log anything that
was previously skipped while logging a directory when logging a new name
(with btrfs_log_new_name()). But later support for incrementally logging
a directory was added in commit dc2872247ec0 ("btrfs: keep track of the
last logged keys when logging a directory"), to avoid checking all dir
items every time we log a directory, so the check to skip dentry logging
added in the first commit should have been removed when the incremental
support for logging a directory was added.

A test case for fstests will follow soon.

Reported-by: Vyacheslav Kovalevsky &lt;slava.kovalevskiy.2014@gmail.com&gt;
Link: https://lore.kernel.org/linux-btrfs/84c4e713-85d6-42b9-8dcf-0722ed26cb05@gmail.com/
Fixes: dc2872247ec0 ("btrfs: keep track of the last logged keys when logging a directory")
Reviewed-by: Boris Burkov &lt;boris@bur.io&gt;
Signed-off-by: Filipe Manana &lt;fdmanana@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>btrfs: don't log conflicting inode if it's a dir moved in the current transaction</title>
<updated>2025-12-08T20:46:47Z</updated>
<author>
<name>Filipe Manana</name>
<email>fdmanana@suse.com</email>
</author>
<published>2025-11-27T16:35:59Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=266273eaf4d99475f1ae57f687b3e42bc71ec6f0'/>
<id>urn:sha1:266273eaf4d99475f1ae57f687b3e42bc71ec6f0</id>
<content type='text'>
We can't log a conflicting inode if it's a directory and it was moved
from one parent directory to another parent directory in the current
transaction, as this can result an attempt to have a directory with
two hard links during log replay, one for the old parent directory and
another for the new parent directory.

The following scenario triggers that issue:

1) We have directories "dir1" and "dir2" created in a past transaction.
   Directory "dir1" has inode A as its parent directory;

2) We move "dir1" to some other directory;

3) We create a file with the name "dir1" in directory inode A;

4) We fsync the new file. This results in logging the inode of the new file
   and the inode for the directory "dir1" that was previously moved in the
   current transaction. So the log tree has the INODE_REF item for the
   new location of "dir1";

5) We move the new file to some other directory. This results in updating
   the log tree to included the new INODE_REF for the new location of the
   file and removes the INODE_REF for the old location. This happens
   during the rename when we call btrfs_log_new_name();

6) We fsync the file, and that persists the log tree changes done in the
   previous step (btrfs_log_new_name() only updates the log tree in
   memory);

7) We have a power failure;

8) Next time the fs is mounted, log replay happens and when processing
   the inode for directory "dir1" we find a new INODE_REF and add that
   link, but we don't remove the old link of the inode since we have
   not logged the old parent directory of the directory inode "dir1".

As a result after log replay finishes when we trigger writeback of the
subvolume tree's extent buffers, the tree check will detect that we have
a directory a hard link count of 2 and we get a mount failure.
The errors and stack traces reported in dmesg/syslog are like this:

   [ 3845.729764] BTRFS info (device dm-0): start tree-log replay
   [ 3845.730304] page: refcount:3 mapcount:0 mapping:000000005c8a3027 index:0x1d00 pfn:0x11510c
   [ 3845.731236] memcg:ffff9264c02f4e00
   [ 3845.731751] aops:btree_aops [btrfs] ino:1
   [ 3845.732300] flags: 0x17fffc00000400a(uptodate|private|writeback|node=0|zone=2|lastcpupid=0x1ffff)
   [ 3845.733346] raw: 017fffc00000400a 0000000000000000 dead000000000122 ffff9264d978aea8
   [ 3845.734265] raw: 0000000000001d00 ffff92650e6d4738 00000003ffffffff ffff9264c02f4e00
   [ 3845.735305] page dumped because: eb page dump
   [ 3845.735981] BTRFS critical (device dm-0): corrupt leaf: root=5 block=30408704 slot=6 ino=257, invalid nlink: has 2 expect no more than 1 for dir
   [ 3845.737786] BTRFS info (device dm-0): leaf 30408704 gen 10 total ptrs 17 free space 14881 owner 5
   [ 3845.737789] BTRFS info (device dm-0): refs 4 lock_owner 0 current 30701
   [ 3845.737792] 	item 0 key (256 INODE_ITEM 0) itemoff 16123 itemsize 160
   [ 3845.737794] 		inode generation 3 transid 9 size 16 nbytes 16384
   [ 3845.737795] 		block group 0 mode 40755 links 1 uid 0 gid 0
   [ 3845.737797] 		rdev 0 sequence 2 flags 0x0
   [ 3845.737798] 		atime 1764259517.0
   [ 3845.737800] 		ctime 1764259517.572889464
   [ 3845.737801] 		mtime 1764259517.572889464
   [ 3845.737802] 		otime 1764259517.0
   [ 3845.737803] 	item 1 key (256 INODE_REF 256) itemoff 16111 itemsize 12
   [ 3845.737805] 		index 0 name_len 2
   [ 3845.737807] 	item 2 key (256 DIR_ITEM 2363071922) itemoff 16077 itemsize 34
   [ 3845.737808] 		location key (257 1 0) type 2
   [ 3845.737810] 		transid 9 data_len 0 name_len 4
   [ 3845.737811] 	item 3 key (256 DIR_ITEM 2676584006) itemoff 16043 itemsize 34
   [ 3845.737813] 		location key (258 1 0) type 2
   [ 3845.737814] 		transid 9 data_len 0 name_len 4
   [ 3845.737815] 	item 4 key (256 DIR_INDEX 2) itemoff 16009 itemsize 34
   [ 3845.737816] 		location key (257 1 0) type 2
   [ 3845.737818] 		transid 9 data_len 0 name_len 4
   [ 3845.737819] 	item 5 key (256 DIR_INDEX 3) itemoff 15975 itemsize 34
   [ 3845.737820] 		location key (258 1 0) type 2
   [ 3845.737821] 		transid 9 data_len 0 name_len 4
   [ 3845.737822] 	item 6 key (257 INODE_ITEM 0) itemoff 15815 itemsize 160
   [ 3845.737824] 		inode generation 9 transid 10 size 6 nbytes 0
   [ 3845.737825] 		block group 0 mode 40755 links 2 uid 0 gid 0
   [ 3845.737826] 		rdev 0 sequence 1 flags 0x0
   [ 3845.737827] 		atime 1764259517.572889464
   [ 3845.737828] 		ctime 1764259517.572889464
   [ 3845.737830] 		mtime 1764259517.572889464
   [ 3845.737831] 		otime 1764259517.572889464
   [ 3845.737832] 	item 7 key (257 INODE_REF 256) itemoff 15801 itemsize 14
   [ 3845.737833] 		index 2 name_len 4
   [ 3845.737834] 	item 8 key (257 INODE_REF 258) itemoff 15787 itemsize 14
   [ 3845.737836] 		index 2 name_len 4
   [ 3845.737837] 	item 9 key (257 DIR_ITEM 2507850652) itemoff 15754 itemsize 33
   [ 3845.737838] 		location key (259 1 0) type 1
   [ 3845.737839] 		transid 10 data_len 0 name_len 3
   [ 3845.737840] 	item 10 key (257 DIR_INDEX 2) itemoff 15721 itemsize 33
   [ 3845.737842] 		location key (259 1 0) type 1
   [ 3845.737843] 		transid 10 data_len 0 name_len 3
   [ 3845.737844] 	item 11 key (258 INODE_ITEM 0) itemoff 15561 itemsize 160
   [ 3845.737846] 		inode generation 9 transid 10 size 8 nbytes 0
   [ 3845.737847] 		block group 0 mode 40755 links 1 uid 0 gid 0
   [ 3845.737848] 		rdev 0 sequence 1 flags 0x0
   [ 3845.737849] 		atime 1764259517.572889464
   [ 3845.737850] 		ctime 1764259517.572889464
   [ 3845.737851] 		mtime 1764259517.572889464
   [ 3845.737852] 		otime 1764259517.572889464
   [ 3845.737853] 	item 12 key (258 INODE_REF 256) itemoff 15547 itemsize 14
   [ 3845.737855] 		index 3 name_len 4
   [ 3845.737856] 	item 13 key (258 DIR_ITEM 1843588421) itemoff 15513 itemsize 34
   [ 3845.737857] 		location key (257 1 0) type 2
   [ 3845.737858] 		transid 10 data_len 0 name_len 4
   [ 3845.737860] 	item 14 key (258 DIR_INDEX 2) itemoff 15479 itemsize 34
   [ 3845.737861] 		location key (257 1 0) type 2
   [ 3845.737862] 		transid 10 data_len 0 name_len 4
   [ 3845.737863] 	item 15 key (259 INODE_ITEM 0) itemoff 15319 itemsize 160
   [ 3845.737865] 		inode generation 10 transid 10 size 0 nbytes 0
   [ 3845.737866] 		block group 0 mode 100600 links 1 uid 0 gid 0
   [ 3845.737867] 		rdev 0 sequence 2 flags 0x0
   [ 3845.737868] 		atime 1764259517.580874966
   [ 3845.737869] 		ctime 1764259517.586121869
   [ 3845.737870] 		mtime 1764259517.580874966
   [ 3845.737872] 		otime 1764259517.580874966
   [ 3845.737873] 	item 16 key (259 INODE_REF 257) itemoff 15306 itemsize 13
   [ 3845.737874] 		index 2 name_len 3
   [ 3845.737875] BTRFS error (device dm-0): block=30408704 write time tree block corruption detected
   [ 3845.739448] ------------[ cut here ]------------
   [ 3845.740092] WARNING: CPU: 5 PID: 30701 at fs/btrfs/disk-io.c:335 btree_csum_one_bio+0x25a/0x270 [btrfs]
   [ 3845.741439] Modules linked in: btrfs dm_flakey crc32c_cryptoapi (...)
   [ 3845.750626] CPU: 5 UID: 0 PID: 30701 Comm: mount Tainted: G        W           6.18.0-rc6-btrfs-next-218+ #1 PREEMPT(full)
   [ 3845.752414] Tainted: [W]=WARN
   [ 3845.752828] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014
   [ 3845.754499] RIP: 0010:btree_csum_one_bio+0x25a/0x270 [btrfs]
   [ 3845.755460] Code: 31 f6 48 89 (...)
   [ 3845.758685] RSP: 0018:ffffa8d9c5677678 EFLAGS: 00010246
   [ 3845.759450] RAX: 0000000000000000 RBX: ffff92650e6d4738 RCX: 0000000000000000
   [ 3845.760309] RDX: 0000000000000000 RSI: ffffffff9aab45b9 RDI: ffff9264c4748000
   [ 3845.761239] RBP: ffff9264d4324000 R08: 0000000000000000 R09: ffffa8d9c5677468
   [ 3845.762607] R10: ffff926bdc1fffa8 R11: 0000000000000003 R12: ffffa8d9c5677680
   [ 3845.764099] R13: 0000000000004000 R14: ffff9264dd624000 R15: ffff9264d978aba8
   [ 3845.765094] FS:  00007f751fa5a840(0000) GS:ffff926c42a82000(0000) knlGS:0000000000000000
   [ 3845.766226] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
   [ 3845.766970] CR2: 0000558df1815380 CR3: 000000010ed88003 CR4: 0000000000370ef0
   [ 3845.768009] Call Trace:
   [ 3845.768392]  &lt;TASK&gt;
   [ 3845.768714]  btrfs_submit_bbio+0x6ee/0x7f0 [btrfs]
   [ 3845.769640]  ? write_one_eb+0x28e/0x340 [btrfs]
   [ 3845.770588]  btree_write_cache_pages+0x2f0/0x550 [btrfs]
   [ 3845.771286]  ? alloc_extent_state+0x19/0x100 [btrfs]
   [ 3845.771967]  ? merge_next_state+0x1a/0x90 [btrfs]
   [ 3845.772586]  ? set_extent_bit+0x233/0x8b0 [btrfs]
   [ 3845.773198]  ? xas_load+0x9/0xc0
   [ 3845.773589]  ? xas_find+0x14d/0x1a0
   [ 3845.773969]  do_writepages+0xc6/0x160
   [ 3845.774367]  filemap_fdatawrite_wbc+0x48/0x60
   [ 3845.775003]  __filemap_fdatawrite_range+0x5b/0x80
   [ 3845.775902]  btrfs_write_marked_extents+0x61/0x170 [btrfs]
   [ 3845.776707]  btrfs_write_and_wait_transaction+0x4e/0xc0 [btrfs]
   [ 3845.777379]  ? _raw_spin_unlock_irqrestore+0x23/0x40
   [ 3845.777923]  btrfs_commit_transaction+0x5ea/0xd20 [btrfs]
   [ 3845.778551]  ? _raw_spin_unlock+0x15/0x30
   [ 3845.778986]  ? release_extent_buffer+0x34/0x160 [btrfs]
   [ 3845.779659]  btrfs_recover_log_trees+0x7a3/0x7c0 [btrfs]
   [ 3845.780416]  ? __pfx_replay_one_buffer+0x10/0x10 [btrfs]
   [ 3845.781499]  open_ctree+0x10bb/0x15f0 [btrfs]
   [ 3845.782194]  btrfs_get_tree.cold+0xb/0x16c [btrfs]
   [ 3845.782764]  ? fscontext_read+0x15c/0x180
   [ 3845.783202]  ? rw_verify_area+0x50/0x180
   [ 3845.783667]  vfs_get_tree+0x25/0xd0
   [ 3845.784047]  vfs_cmd_create+0x59/0xe0
   [ 3845.784458]  __do_sys_fsconfig+0x4f6/0x6b0
   [ 3845.784914]  do_syscall_64+0x50/0x1220
   [ 3845.785340]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
   [ 3845.785980] RIP: 0033:0x7f751fc7f4aa
   [ 3845.786759] Code: 73 01 c3 48 (...)
   [ 3845.789951] RSP: 002b:00007ffcdba45dc8 EFLAGS: 00000246 ORIG_RAX: 00000000000001af
   [ 3845.791402] RAX: ffffffffffffffda RBX: 000055ccc8291c20 RCX: 00007f751fc7f4aa
   [ 3845.792688] RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000003
   [ 3845.794308] RBP: 000055ccc8292120 R08: 0000000000000000 R09: 0000000000000000
   [ 3845.795829] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
   [ 3845.797183] R13: 00007f751fe11580 R14: 00007f751fe1326c R15: 00007f751fdf8a23
   [ 3845.798633]  &lt;/TASK&gt;
   [ 3845.799067] ---[ end trace 0000000000000000 ]---
   [ 3845.800215] BTRFS: error (device dm-0) in btrfs_commit_transaction:2553: errno=-5 IO failure (Error while writing out transaction)
   [ 3845.801860] BTRFS warning (device dm-0 state E): Skipping commit of aborted transaction.
   [ 3845.802815] BTRFS error (device dm-0 state EA): Transaction aborted (error -5)
   [ 3845.803728] BTRFS: error (device dm-0 state EA) in cleanup_transaction:2036: errno=-5 IO failure
   [ 3845.805374] BTRFS: error (device dm-0 state EA) in btrfs_replay_log:2083: errno=-5 IO failure (Failed to recover log tree)
   [ 3845.807919] BTRFS error (device dm-0 state EA): open_ctree failed: -5

Fix this by never logging a conflicting inode that is a directory and was
moved in the current transaction (its last_unlink_trans equals the current
transaction) and instead fallback to a transaction commit.

A test case for fstests will follow soon.

Reported-by: Vyacheslav Kovalevsky &lt;slva.kovalevskiy.2014@gmail.com&gt;
Link: https://lore.kernel.org/linux-btrfs/7bbc9419-5c56-450a-b5a0-efeae7457113@gmail.com/
CC: stable@vger.kernel.org # 6.1+
Signed-off-by: Filipe Manana &lt;fdmanana@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>btrfs: remove unnecessary inode key in btrfs_log_all_parents()</title>
<updated>2025-11-25T00:53:33Z</updated>
<author>
<name>Filipe Manana</name>
<email>fdmanana@suse.com</email>
</author>
<published>2025-11-21T16:56:46Z</published>
<link rel='alternate' type='text/html' href='https://universe.0xinfinity.dev/distro/kernel/commit/?id=9e0e6577b3e5e5cf7c1acd178eb648e8f830ba17'/>
<id>urn:sha1:9e0e6577b3e5e5cf7c1acd178eb648e8f830ba17</id>
<content type='text'>
We are setting up an inode key to lookup parent directory inode but all we
need is the inode's objectid. The use of the key was necessary in the past
but since commit 0202e83fdab0 ("btrfs: simplify iget helpers") we only
need the objectid.

So remove the key variable in the stack and use instead a simple u64 for
the inode's objectid.

Reviewed-by: Qu Wenruo &lt;wqu@suse.com&gt;
Reviewed-by: Johannes Thumshirn &lt;johannes.thumshirn@wdc.com&gt;
Signed-off-by: Filipe Manana &lt;fdmanana@suse.com&gt;
Reviewed-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
</feed>
