<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git/fs/btrfs, branch v5.15.209</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=v5.15.209</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=v5.15.209'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/'/>
<updated>2026-06-01T15:35:41+00:00</updated>
<entry>
<title>btrfs: fix double-decrement of bytes_may_use in submit_one_async_extent()</title>
<updated>2026-06-01T15:35:41+00:00</updated>
<author>
<name>Mark Harmstone</name>
<email>mark@harmstone.com</email>
</author>
<published>2026-04-16T17:15:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=f2560f67018aa46b9eba028c1ac3027e205213b4'/>
<id>urn:sha1:f2560f67018aa46b9eba028c1ac3027e205213b4</id>
<content type='text'>
[ Upstream commit 82323b1a7088b7a5c3e528a5d634bff447fa286f ]

submit_one_async_extent() calls btrfs_reserve_extent(), which decrements
bytes_may_use. If the call btrfs_create_io_em() fails, we jump to
out_free_reserve, which calls extent_clear_unlock_delalloc().

Because we're specifying EXTENT_DO_ACCOUNTING, i.e.
EXTENT_CLEAR_META_RESV | EXTENT_CLEAR_DATA_RESV, this decreases
bytes_may_use again. This can lead to problems later on, as an initial
write can fail only for the writeback to silently ENOSPC.

Fix this by replacing EXTENT_DO_ACCOUNTING with EXTENT_CLEAR_META_RESV.
This parallels a4fe134fc1d8eb ("btrfs: fix a double release on reserved
extents in cow_one_range()"), which is the same fix in cow_one_range().

Fixes: 151a41bc46df ("Btrfs: fix what bits we clear when erroring out from delalloc")
Reviewed-by: Qu Wenruo &lt;wqu@suse.com&gt;
Signed-off-by: Mark Harmstone &lt;mark@harmstone.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>btrfs: lock the inode in shared mode before starting fiemap</title>
<updated>2026-06-01T15:35:11+00:00</updated>
<author>
<name>Filipe Manana</name>
<email>fdmanana@suse.com</email>
</author>
<published>2026-04-23T07:38:42+00:00</published>
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<id>urn:sha1:e425191073a80906d8502b5179471cc58b0b9e9a</id>
<content type='text'>
[ Upstream commit 519b7e13b5ae8dd38da1e52275705343be6bb508 ]

Currently fiemap does not take the inode's lock (VFS lock), it only locks
a file range in the inode's io tree. This however can lead to a deadlock
if we have a concurrent fsync on the file and fiemap code triggers a fault
when accessing the user space buffer with fiemap_fill_next_extent(). The
deadlock happens on the inode's i_mmap_lock semaphore, which is taken both
by fsync and btrfs_page_mkwrite(). This deadlock was recently reported by
syzbot and triggers a trace like the following:

   task:syz-executor361 state:D stack:20264 pid:5668  ppid:5119   flags:0x00004004
   Call Trace:
    &lt;TASK&gt;
    context_switch kernel/sched/core.c:5293 [inline]
    __schedule+0x995/0xe20 kernel/sched/core.c:6606
    schedule+0xcb/0x190 kernel/sched/core.c:6682
    wait_on_state fs/btrfs/extent-io-tree.c:707 [inline]
    wait_extent_bit+0x577/0x6f0 fs/btrfs/extent-io-tree.c:751
    lock_extent+0x1c2/0x280 fs/btrfs/extent-io-tree.c:1742
    find_lock_delalloc_range+0x4e6/0x9c0 fs/btrfs/extent_io.c:488
    writepage_delalloc+0x1ef/0x540 fs/btrfs/extent_io.c:1863
    __extent_writepage+0x736/0x14e0 fs/btrfs/extent_io.c:2174
    extent_write_cache_pages+0x983/0x1220 fs/btrfs/extent_io.c:3091
    extent_writepages+0x219/0x540 fs/btrfs/extent_io.c:3211
    do_writepages+0x3c3/0x680 mm/page-writeback.c:2581
    filemap_fdatawrite_wbc+0x11e/0x170 mm/filemap.c:388
    __filemap_fdatawrite_range mm/filemap.c:421 [inline]
    filemap_fdatawrite_range+0x175/0x200 mm/filemap.c:439
    btrfs_fdatawrite_range fs/btrfs/file.c:3850 [inline]
    start_ordered_ops fs/btrfs/file.c:1737 [inline]
    btrfs_sync_file+0x4ff/0x1190 fs/btrfs/file.c:1839
    generic_write_sync include/linux/fs.h:2885 [inline]
    btrfs_do_write_iter+0xcd3/0x1280 fs/btrfs/file.c:1684
    call_write_iter include/linux/fs.h:2189 [inline]
    new_sync_write fs/read_write.c:491 [inline]
    vfs_write+0x7dc/0xc50 fs/read_write.c:584
    ksys_write+0x177/0x2a0 fs/read_write.c:637
    do_syscall_x64 arch/x86/entry/common.c:50 [inline]
    do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
    entry_SYSCALL_64_after_hwframe+0x63/0xcd
   RIP: 0033:0x7f7d4054e9b9
   RSP: 002b:00007f7d404fa2f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
   RAX: ffffffffffffffda RBX: 00007f7d405d87a0 RCX: 00007f7d4054e9b9
   RDX: 0000000000000090 RSI: 0000000020000000 RDI: 0000000000000006
   RBP: 00007f7d405a51d0 R08: 0000000000000000 R09: 0000000000000000
   R10: 0000000000000000 R11: 0000000000000246 R12: 61635f65646f6e69
   R13: 65646f7475616f6e R14: 7261637369646f6e R15: 00007f7d405d87a8
    &lt;/TASK&gt;
   INFO: task syz-executor361:5697 blocked for more than 145 seconds.
         Not tainted 6.2.0-rc3-syzkaller-00376-g7c6984405241 #0
   "echo 0 &gt; /proc/sys/kernel/hung_task_timeout_secs" disables this message.
   task:syz-executor361 state:D stack:21216 pid:5697  ppid:5119   flags:0x00004004
   Call Trace:
    &lt;TASK&gt;
    context_switch kernel/sched/core.c:5293 [inline]
    __schedule+0x995/0xe20 kernel/sched/core.c:6606
    schedule+0xcb/0x190 kernel/sched/core.c:6682
    rwsem_down_read_slowpath+0x5f9/0x930 kernel/locking/rwsem.c:1095
    __down_read_common+0x54/0x2a0 kernel/locking/rwsem.c:1260
    btrfs_page_mkwrite+0x417/0xc80 fs/btrfs/inode.c:8526
    do_page_mkwrite+0x19e/0x5e0 mm/memory.c:2947
    wp_page_shared+0x15e/0x380 mm/memory.c:3295
    handle_pte_fault mm/memory.c:4949 [inline]
    __handle_mm_fault mm/memory.c:5073 [inline]
    handle_mm_fault+0x1b79/0x26b0 mm/memory.c:5219
    do_user_addr_fault+0x69b/0xcb0 arch/x86/mm/fault.c:1428
    handle_page_fault arch/x86/mm/fault.c:1519 [inline]
    exc_page_fault+0x7a/0x110 arch/x86/mm/fault.c:1575
    asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570
   RIP: 0010:copy_user_short_string+0xd/0x40 arch/x86/lib/copy_user_64.S:233
   Code: 74 0a 89 (...)
   RSP: 0018:ffffc9000570f330 EFLAGS: 00050202
   RAX: ffffffff843e6601 RBX: 00007fffffffefc8 RCX: 0000000000000007
   RDX: 0000000000000000 RSI: ffffc9000570f3e0 RDI: 0000000020000120
   RBP: ffffc9000570f490 R08: 0000000000000000 R09: fffff52000ae1e83
   R10: fffff52000ae1e83 R11: 1ffff92000ae1e7c R12: 0000000000000038
   R13: ffffc9000570f3e0 R14: 0000000020000120 R15: ffffc9000570f3e0
    copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline]
    raw_copy_to_user arch/x86/include/asm/uaccess_64.h:58 [inline]
    _copy_to_user+0xe9/0x130 lib/usercopy.c:34
    copy_to_user include/linux/uaccess.h:169 [inline]
    fiemap_fill_next_extent+0x22e/0x410 fs/ioctl.c:144
    emit_fiemap_extent+0x22d/0x3c0 fs/btrfs/extent_io.c:3458
    fiemap_process_hole+0xa00/0xad0 fs/btrfs/extent_io.c:3716
    extent_fiemap+0xe27/0x2100 fs/btrfs/extent_io.c:3922
    btrfs_fiemap+0x172/0x1e0 fs/btrfs/inode.c:8209
    ioctl_fiemap fs/ioctl.c:219 [inline]
    do_vfs_ioctl+0x185b/0x2980 fs/ioctl.c:810
    __do_sys_ioctl fs/ioctl.c:868 [inline]
    __se_sys_ioctl+0x83/0x170 fs/ioctl.c:856
    do_syscall_x64 arch/x86/entry/common.c:50 [inline]
    do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
    entry_SYSCALL_64_after_hwframe+0x63/0xcd
   RIP: 0033:0x7f7d4054e9b9
   RSP: 002b:00007f7d390d92f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
   RAX: ffffffffffffffda RBX: 00007f7d405d87b0 RCX: 00007f7d4054e9b9
   RDX: 0000000020000100 RSI: 00000000c020660b RDI: 0000000000000005
   RBP: 00007f7d405a51d0 R08: 00007f7d390d9700 R09: 0000000000000000
   R10: 00007f7d390d9700 R11: 0000000000000246 R12: 61635f65646f6e69
   R13: 65646f7475616f6e R14: 7261637369646f6e R15: 00007f7d405d87b8
    &lt;/TASK&gt;

What happens is the following:

1) Task A is doing an fsync, enters btrfs_sync_file() and flushes delalloc
   before locking the inode and the i_mmap_lock semaphore, that is, before
   calling btrfs_inode_lock();

2) After task A flushes delalloc and before it calls btrfs_inode_lock(),
   another task dirties a page;

3) Task B starts a fiemap without FIEMAP_FLAG_SYNC, so the page dirtied
   at step 2 remains dirty and unflushed. Then when it enters
   extent_fiemap() and it locks a file range that includes the range of
   the page dirtied in step 2;

4) Task A calls btrfs_inode_lock() and locks the inode (VFS lock) and the
   inode's i_mmap_lock semaphore in write mode. Then it tries to flush
   delalloc by calling start_ordered_ops(), which will block, at
   find_lock_delalloc_range(), when trying to lock the range of the page
   dirtied at step 2, since this range was locked by the fiemap task (at
   step 3);

5) Task B generates a page fault when accessing the user space fiemap
   buffer with a call to fiemap_fill_next_extent().

   The fault handler needs to call btrfs_page_mkwrite() for some other
   page of our inode, and there we deadlock when trying to lock the
   inode's i_mmap_lock semaphore in read mode, since the fsync task locked
   it in write mode (step 4) and the fsync task can not progress because
   it's waiting to lock a file range that is currently locked by us (the
   fiemap task, step 3).

Fix this by taking the inode's lock (VFS lock) in shared mode when
entering fiemap. This effectively serializes fiemap with fsync (except the
most expensive part of fsync, the log sync), preventing this deadlock.

Reported-by: syzbot+cc35f55c41e34c30dcb5@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/00000000000032dc7305f2a66f46@google.com/
CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Josef Bacik &lt;josef@toxicpanda.com&gt;
Signed-off-by: Filipe Manana &lt;fdmanana@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: Robert Garcia &lt;rob_garcia@163.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>btrfs: do not strictly require dirty metadata threshold for metadata writepages</title>
<updated>2026-06-01T15:35:09+00:00</updated>
<author>
<name>Qu Wenruo</name>
<email>wqu@suse.com</email>
</author>
<published>2026-03-03T06:00:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=6a8b6242eaa1dd7a0de2d6de6420d10ffe68db90'/>
<id>urn:sha1:6a8b6242eaa1dd7a0de2d6de6420d10ffe68db90</id>
<content type='text'>
[ Upstream commit 4e159150a9a56d66d247f4b5510bed46fe58aa1c ]

[BUG]
There is an internal report that over 1000 processes are
waiting at the io_schedule_timeout() of balance_dirty_pages(), causing
a system hang and trigger a kernel coredump.

The kernel is v6.4 kernel based, but the root problem still applies to
any upstream kernel before v6.18.

[CAUSE]
&gt;From Jan Kara for his wisdom on the dirty page balance behavior first.

  This cgroup dirty limit was what was actually playing the role here
  because the cgroup had only a small amount of memory and so the dirty
  limit for it was something like 16MB.

  Dirty throttling is responsible for enforcing that nobody can dirty
  (significantly) more dirty memory than there's dirty limit. Thus when
  a task is dirtying pages it periodically enters into balance_dirty_pages()
  and we let it sleep there to slow down the dirtying.

  When the system is over dirty limit already (either globally or within
  a cgroup of the running task), we will not let the task exit from
  balance_dirty_pages() until the number of dirty pages drops below the
  limit.

  So in this particular case, as I already mentioned, there was a cgroup
  with relatively small amount of memory and as a result with dirty limit
  set at 16MB. A task from that cgroup has dirtied about 28MB worth of
  pages in btrfs btree inode and these were practically the only dirty
  pages in that cgroup.

So that means the only way to reduce the dirty pages of that cgroup is
to writeback the dirty pages of btrfs btree inode, and only after that
those processes can exit balance_dirty_pages().

Now back to the btrfs part, btree_writepages() is responsible for
writing back dirty btree inode pages.

The problem here is, there is a btrfs internal threshold that if the
btree inode's dirty bytes are below the 32M threshold, it will not
do any writeback.

This behavior is to batch as much metadata as possible so we won't write
back those tree blocks and then later re-COW them again for another
modification.

This internal 32MiB is higher than the existing dirty page size (28MiB),
meaning no writeback will happen, causing a deadlock between btrfs and
cgroup:

- Btrfs doesn't want to write back btree inode until more dirty pages

- Cgroup/MM doesn't want more dirty pages for btrfs btree inode
  Thus any process touching that btree inode is put into sleep until
  the number of dirty pages is reduced.

Thanks Jan Kara a lot for the analysis of the root cause.

[ENHANCEMENT]
Since kernel commit b55102826d7d ("btrfs: set AS_KERNEL_FILE on the
btree_inode"), btrfs btree inode pages will only be charged to the root
cgroup which should have a much larger limit than btrfs' 32MiB
threshold.
So it should not affect newer kernels.

But for all current LTS kernels, they are all affected by this problem,
and backporting the whole AS_KERNEL_FILE may not be a good idea.

Even for newer kernels I still think it's a good idea to get
rid of the internal threshold at btree_writepages(), since for most cases
cgroup/MM has a better view of full system memory usage than btrfs' fixed
threshold.

For internal callers using btrfs_btree_balance_dirty() since that
function is already doing internal threshold check, we don't need to
bother them.

But for external callers of btree_writepages(), just respect their
requests and write back whatever they want, ignoring the internal
btrfs threshold to avoid such deadlock on btree inode dirty page
balancing.

CC: stable@vger.kernel.org
CC: Jan Kara &lt;jack@suse.cz&gt;
Reviewed-by: Boris Burkov &lt;boris@bur.io&gt;
Signed-off-by: Qu Wenruo &lt;wqu@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
[ The context change is due to the commit 41044b41ad2c
("btrfs: add helper to get fs_info from struct inode pointer")
in v6.9 and the commit c66f2afc7148
("btrfs: remove pointless writepages callback wrapper")
in v6.10 which are irrelevant to the logic of this patch. ]
Signed-off-by: Rahul Sharma &lt;black.hawk@163.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>btrfs: send: check for inline extents in range_is_hole_in_parent()</title>
<updated>2026-06-01T15:35:09+00:00</updated>
<author>
<name>Qu Wenruo</name>
<email>wqu@suse.com</email>
</author>
<published>2026-03-03T01:45:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=901e581bfc44d181f7d9c3f11880dac3e89deb2e'/>
<id>urn:sha1:901e581bfc44d181f7d9c3f11880dac3e89deb2e</id>
<content type='text'>
[ Upstream commit 08b096c1372cd69627f4f559fb47c9fb67a52b39 ]

Before accessing the disk_bytenr field of a file extent item we need
to check if we are dealing with an inline extent.
This is because for inline extents their data starts at the offset of
the disk_bytenr field. So accessing the disk_bytenr
means we are accessing inline data or in case the inline data is less
than 8 bytes we can actually cause an invalid
memory access if this inline extent item is the first item in the leaf
or access metadata from other items.

Fixes: 82bfb2e7b645 ("Btrfs: incremental send, fix unnecessary hole writes for sparse files")
Reviewed-by: Filipe Manana &lt;fdmanana@suse.com&gt;
Signed-off-by: Qu Wenruo &lt;wqu@suse.com&gt;
Reviewed-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
[ Avoid leaking the path by using { ret = 0; goto out; } instead of
returning directly. ]
Signed-off-by: Alva Lan &lt;alvalan9@foxmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>btrfs: reject root items with drop_progress and zero drop_level</title>
<updated>2026-04-18T08:33:29+00:00</updated>
<author>
<name>ZhengYuan Huang</name>
<email>gality369@gmail.com</email>
</author>
<published>2026-03-12T00:14:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=bedaf7d0b9d793e116f16b4d9a7dbc94bcc80443'/>
<id>urn:sha1:bedaf7d0b9d793e116f16b4d9a7dbc94bcc80443</id>
<content type='text'>
[ Upstream commit b17b79ff896305fd74980a5f72afec370ee88ca4 ]

[BUG]
When recovering relocation at mount time, merge_reloc_root() and
btrfs_drop_snapshot() both use BUG_ON(level == 0) to guard against
an impossible state: a non-zero drop_progress combined with a zero
drop_level in a root_item, which can be triggered:

------------[ cut here ]------------
kernel BUG at fs/btrfs/relocation.c:1545!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 1 UID: 0 PID: 283 ... Tainted: 6.18.0+ #16 PREEMPT(voluntary)
Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
Hardware name: QEMU Ubuntu 24.04 PC v2, BIOS 1.16.3-debian-1.16.3-2
RIP: 0010:merge_reloc_root+0x1266/0x1650 fs/btrfs/relocation.c:1545
Code: ffff0000 00004589 d7e9acfa ffffe8a1 79bafebe 02000000
Call Trace:
 merge_reloc_roots+0x295/0x890 fs/btrfs/relocation.c:1861
 btrfs_recover_relocation+0xd6e/0x11d0 fs/btrfs/relocation.c:4195
 btrfs_start_pre_rw_mount+0xa4d/0x1810 fs/btrfs/disk-io.c:3130
 open_ctree+0x5824/0x5fe0 fs/btrfs/disk-io.c:3640
 btrfs_fill_super fs/btrfs/super.c:987 [inline]
 btrfs_get_tree_super fs/btrfs/super.c:1951 [inline]
 btrfs_get_tree_subvol fs/btrfs/super.c:2094 [inline]
 btrfs_get_tree+0x111c/0x2190 fs/btrfs/super.c:2128
 vfs_get_tree+0x9a/0x370 fs/super.c:1758
 fc_mount fs/namespace.c:1199 [inline]
 do_new_mount_fc fs/namespace.c:3642 [inline]
 do_new_mount fs/namespace.c:3718 [inline]
 path_mount+0x5b8/0x1ea0 fs/namespace.c:4028
 do_mount fs/namespace.c:4041 [inline]
 __do_sys_mount fs/namespace.c:4229 [inline]
 __se_sys_mount fs/namespace.c:4206 [inline]
 __x64_sys_mount+0x282/0x320 fs/namespace.c:4206
 ...
RIP: 0033:0x7f969c9a8fde
Code: 0f1f4000 48c7c2b0 fffffff7 d8648902 b8ffffff ffc3660f
---[ end trace 0000000000000000 ]---

The bug is reproducible on 7.0.0-rc2-next-20260310 with our dynamic
metadata fuzzing tool that corrupts btrfs metadata at runtime.

[CAUSE]
A non-zero drop_progress.objectid means an interrupted
btrfs_drop_snapshot() left a resume point on disk, and in that case
drop_level must be greater than 0 because the checkpoint is only
saved at internal node levels.

Although this invariant is enforced when the kernel writes the root
item, it is not validated when the root item is read back from disk.
That allows on-disk corruption to provide an invalid state with
drop_progress.objectid != 0 and drop_level == 0.

When relocation recovery later processes such a root item,
merge_reloc_root() reads drop_level and hits BUG_ON(level == 0). The
same invalid metadata can also trigger the corresponding BUG_ON() in
btrfs_drop_snapshot().

[FIX]
Fix this by validating the root_item invariant in tree-checker when
reading root items from disk: if drop_progress.objectid is non-zero,
drop_level must also be non-zero. Reject such malformed metadata with
-EUCLEAN before it reaches merge_reloc_root() or btrfs_drop_snapshot()
and triggers the BUG_ON.

After the fix, the same corruption is correctly rejected by tree-checker
and the BUG_ON is no longer triggered.

Reviewed-by: Qu Wenruo &lt;wqu@suse.com&gt;
Signed-off-by: ZhengYuan Huang &lt;gality369@gmail.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>btrfs: don't take device_list_mutex when querying zone info</title>
<updated>2026-04-18T08:33:29+00:00</updated>
<author>
<name>Johannes Thumshirn</name>
<email>johannes.thumshirn@wdc.com</email>
</author>
<published>2026-03-03T10:53:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=8917b72adff3c7f292dd496035de49b94aa0e136'/>
<id>urn:sha1:8917b72adff3c7f292dd496035de49b94aa0e136</id>
<content type='text'>
[ Upstream commit 77603ab10429fe713a03345553ca8dbbfb1d91c6 ]

Shin'ichiro reported sporadic hangs when running generic/013 in our CI
system. When enabling lockdep, there is a lockdep splat when calling
btrfs_get_dev_zone_info_all_devices() in the mount path that can be
triggered by i.e. generic/013:

  ======================================================
  WARNING: possible circular locking dependency detected
  7.0.0-rc1+ #355 Not tainted
  ------------------------------------------------------
  mount/1043 is trying to acquire lock:
  ffff8881020b5470 (&amp;vblk-&gt;vdev_mutex){+.+.}-{4:4}, at: virtblk_report_zones+0xda/0x430

  but task is already holding lock:
  ffff888102a738e0 (&amp;fs_devs-&gt;device_list_mutex){+.+.}-{4:4}, at: btrfs_get_dev_zone_info_all_devices+0x45/0x90

  which lock already depends on the new lock.

  the existing dependency chain (in reverse order) is:

  -&gt; #4 (&amp;fs_devs-&gt;device_list_mutex){+.+.}-{4:4}:
	 __mutex_lock+0xa3/0x1360
	 btrfs_create_pending_block_groups+0x1f4/0x9d0
	 __btrfs_end_transaction+0x3e/0x2e0
	 btrfs_zoned_reserve_data_reloc_bg+0x2f8/0x390
	 open_ctree+0x1934/0x23db
	 btrfs_get_tree.cold+0x105/0x26c
	 vfs_get_tree+0x28/0xb0
	 __do_sys_fsconfig+0x324/0x680
	 do_syscall_64+0x92/0x4f0
	 entry_SYSCALL_64_after_hwframe+0x76/0x7e

  -&gt; #3 (btrfs_trans_num_extwriters){++++}-{0:0}:
	 join_transaction+0xc2/0x5c0
	 start_transaction+0x17c/0xbc0
	 btrfs_zoned_reserve_data_reloc_bg+0x2b4/0x390
	 open_ctree+0x1934/0x23db
	 btrfs_get_tree.cold+0x105/0x26c
	 vfs_get_tree+0x28/0xb0
	 __do_sys_fsconfig+0x324/0x680
	 do_syscall_64+0x92/0x4f0
	 entry_SYSCALL_64_after_hwframe+0x76/0x7e

  -&gt; #2 (btrfs_trans_num_writers){++++}-{0:0}:
	 lock_release+0x163/0x4b0
	 __btrfs_end_transaction+0x1c7/0x2e0
	 btrfs_dirty_inode+0x6f/0xd0
	 touch_atime+0xe5/0x2c0
	 btrfs_file_mmap_prepare+0x65/0x90
	 __mmap_region+0x4b9/0xf00
	 mmap_region+0xf7/0x120
	 do_mmap+0x43d/0x610
	 vm_mmap_pgoff+0xd6/0x190
	 ksys_mmap_pgoff+0x7e/0xc0
	 do_syscall_64+0x92/0x4f0
	 entry_SYSCALL_64_after_hwframe+0x76/0x7e

  -&gt; #1 (&amp;mm-&gt;mmap_lock){++++}-{4:4}:
	 __might_fault+0x68/0xa0
	 _copy_to_user+0x22/0x70
	 blkdev_copy_zone_to_user+0x22/0x40
	 virtblk_report_zones+0x282/0x430
	 blkdev_report_zones_ioctl+0xfd/0x130
	 blkdev_ioctl+0x20f/0x2c0
	 __x64_sys_ioctl+0x86/0xd0
	 do_syscall_64+0x92/0x4f0
	 entry_SYSCALL_64_after_hwframe+0x76/0x7e

  -&gt; #0 (&amp;vblk-&gt;vdev_mutex){+.+.}-{4:4}:
	 __lock_acquire+0x1522/0x2680
	 lock_acquire+0xd5/0x2f0
	 __mutex_lock+0xa3/0x1360
	 virtblk_report_zones+0xda/0x430
	 blkdev_report_zones_cached+0x162/0x190
	 btrfs_get_dev_zones+0xdc/0x2e0
	 btrfs_get_dev_zone_info+0x219/0xe80
	 btrfs_get_dev_zone_info_all_devices+0x62/0x90
	 open_ctree+0x1200/0x23db
	 btrfs_get_tree.cold+0x105/0x26c
	 vfs_get_tree+0x28/0xb0
	 __do_sys_fsconfig+0x324/0x680
	 do_syscall_64+0x92/0x4f0
	 entry_SYSCALL_64_after_hwframe+0x76/0x7e

  other info that might help us debug this:

  Chain exists of:
    &amp;vblk-&gt;vdev_mutex --&gt; btrfs_trans_num_extwriters --&gt; &amp;fs_devs-&gt;device_list_mutex

   Possible unsafe locking scenario:

	 CPU0                    CPU1
	 ----                    ----
    lock(&amp;fs_devs-&gt;device_list_mutex);
				 lock(btrfs_trans_num_extwriters);
				 lock(&amp;fs_devs-&gt;device_list_mutex);
    lock(&amp;vblk-&gt;vdev_mutex);

   *** DEADLOCK ***

  3 locks held by mount/1043:
   #0: ffff88811063e878 (&amp;fc-&gt;uapi_mutex){+.+.}-{4:4}, at: __do_sys_fsconfig+0x2ae/0x680
   #1: ffff88810cb9f0e8 (&amp;type-&gt;s_umount_key#31/1){+.+.}-{4:4}, at: alloc_super+0xc0/0x3e0
   #2: ffff888102a738e0 (&amp;fs_devs-&gt;device_list_mutex){+.+.}-{4:4}, at: btrfs_get_dev_zone_info_all_devices+0x45/0x90

  stack backtrace:
  CPU: 2 UID: 0 PID: 1043 Comm: mount Not tainted 7.0.0-rc1+ #355 PREEMPT(full)
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-9.fc43 06/10/2025
  Call Trace:
   &lt;TASK&gt;
   dump_stack_lvl+0x5b/0x80
   print_circular_bug.cold+0x18d/0x1d8
   check_noncircular+0x10d/0x130
   __lock_acquire+0x1522/0x2680
   ? vmap_small_pages_range_noflush+0x3ef/0x820
   lock_acquire+0xd5/0x2f0
   ? virtblk_report_zones+0xda/0x430
   ? lock_is_held_type+0xcd/0x130
   __mutex_lock+0xa3/0x1360
   ? virtblk_report_zones+0xda/0x430
   ? virtblk_report_zones+0xda/0x430
   ? __pfx_copy_zone_info_cb+0x10/0x10
   ? virtblk_report_zones+0xda/0x430
   virtblk_report_zones+0xda/0x430
   ? __pfx_copy_zone_info_cb+0x10/0x10
   blkdev_report_zones_cached+0x162/0x190
   ? __pfx_copy_zone_info_cb+0x10/0x10
   btrfs_get_dev_zones+0xdc/0x2e0
   btrfs_get_dev_zone_info+0x219/0xe80
   btrfs_get_dev_zone_info_all_devices+0x62/0x90
   open_ctree+0x1200/0x23db
   btrfs_get_tree.cold+0x105/0x26c
   ? rcu_is_watching+0x18/0x50
   vfs_get_tree+0x28/0xb0
   __do_sys_fsconfig+0x324/0x680
   do_syscall_64+0x92/0x4f0
   entry_SYSCALL_64_after_hwframe+0x76/0x7e
  RIP: 0033:0x7f615e27a40e
  RSP: 002b:00007fff11b18fb8 EFLAGS: 00000246 ORIG_RAX: 00000000000001af
  RAX: ffffffffffffffda RBX: 000055572e92ab10 RCX: 00007f615e27a40e
  RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000003
  RBP: 00007fff11b19100 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
  R13: 000055572e92bc40 R14: 00007f615e3faa60 R15: 000055572e92bd08
   &lt;/TASK&gt;

Don't hold the device_list_mutex while calling into
btrfs_get_dev_zone_info() in btrfs_get_dev_zone_info_all_devices() to
mitigate the issue. This is safe, as no other thread can touch the device
list at the moment of execution.

Reported-by: Shin'ichiro Kawasaki &lt;shinichiro.kawasaki@wdc.com&gt;
Reviewed-by: Damien Le Moal &lt;dlemoal@kernel.org&gt;
Signed-off-by: Johannes Thumshirn &lt;johannes.thumshirn@wdc.com&gt;
Reviewed-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>btrfs: fix lost error when running device stats on multiple devices fs</title>
<updated>2026-04-18T08:33:28+00:00</updated>
<author>
<name>Filipe Manana</name>
<email>fdmanana@suse.com</email>
</author>
<published>2026-03-18T16:17:59+00:00</published>
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<id>urn:sha1:b70bd0378cac5749c32fb27193c85e1c77d29a58</id>
<content type='text'>
[ Upstream commit 1c37d896b12dfd0d4c96e310b0033c6676933917 ]

Whenever we get an error updating the device stats item for a device in
btrfs_run_dev_stats() we allow the loop to go to the next device, and if
updating the stats item for the next device succeeds, we end up losing
the error we had from the previous device.

Fix this by breaking out of the loop once we get an error and make sure
it's returned to the caller. Since we are in the transaction commit path
(and in the critical section actually), returning the error will result
in a transaction abort.

Fixes: 733f4fbbc108 ("Btrfs: read device stats on mount, write modified ones during commit")
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;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>btrfs: fix super block offset in error message in btrfs_validate_super()</title>
<updated>2026-04-18T08:33:28+00:00</updated>
<author>
<name>Mark Harmstone</name>
<email>mark@harmstone.com</email>
</author>
<published>2026-02-17T17:35:42+00:00</published>
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<id>urn:sha1:fb21c8958e5a85849050b05639a90d1af979ed66</id>
<content type='text'>
[ Upstream commit b52fe51f724385b3ed81e37e510a4a33107e8161 ]

Fix the superblock offset mismatch error message in
btrfs_validate_super(): we changed it so that it considers all the
superblocks, but the message still assumes we're only looking at the
first one.

The change from %u to %llu is because we're changing from a constant to
a u64.

Fixes: 069ec957c35e ("btrfs: Refactor btrfs_check_super_valid")
Reviewed-by: Qu Wenruo &lt;wqu@suse.com&gt;
Signed-off-by: Mark Harmstone &lt;mark@harmstone.com&gt;
Reviewed-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>btrfs: tree-checker: fix misleading root drop_level error message</title>
<updated>2026-04-18T08:33:19+00:00</updated>
<author>
<name>ZhengYuan Huang</name>
<email>gality369@gmail.com</email>
</author>
<published>2026-03-12T00:33:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=fde0e471f84fe5e356879fdcbfc9dd5ccfb8d99f'/>
<id>urn:sha1:fde0e471f84fe5e356879fdcbfc9dd5ccfb8d99f</id>
<content type='text'>
[ Upstream commit fc1cd1f18c34f91e78362f9629ab9fd43b9dcab9 ]

Fix tree-checker error message to report "invalid root drop_level"
instead of the misleading "invalid root level".

Fixes: 259ee7754b67 ("btrfs: tree-checker: Add ROOT_ITEM check")
Reviewed-by: Qu Wenruo &lt;wqu@suse.com&gt;
Signed-off-by: ZhengYuan Huang &lt;gality369@gmail.com&gt;
Reviewed-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>btrfs: abort transaction on failure to update root in the received subvol ioctl</title>
<updated>2026-04-18T08:33:16+00:00</updated>
<author>
<name>Filipe Manana</name>
<email>fdmanana@suse.com</email>
</author>
<published>2026-02-27T00:02:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=65ecbe6b424e704beea2420426d732fc22dcb385'/>
<id>urn:sha1:65ecbe6b424e704beea2420426d732fc22dcb385</id>
<content type='text'>
commit 0f475ee0ebce5c9492b260027cd95270191675fa upstream.

If we failed to update the root we don't abort the transaction, which is
wrong since we already used the transaction to remove an item from the
uuid tree.

Fixes: dd5f9615fc5c ("Btrfs: maintain subvolume items in the UUID tree")
CC: stable@vger.kernel.org # 3.12+
Reviewed-by: Anand Jain &lt;asj@kernel.org&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;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
</feed>
