Re: [PATCH] fs: use namespace_{lock,unlock} in dissolve_on_fput()

From: Christian Brauner
Date: Fri Apr 11 2025 - 10:11:40 EST


On Thu, 10 Apr 2025 17:05:42 +0200, Jan Stancek wrote:
> In commit b73ec10a4587 ("fs: add fastpath for dissolve_on_fput()"),
> the namespace_{lock,unlock} has been replaced with scoped_guard
> using the namespace_sem. This however now also skips processing of
> 'unmounted' list in namespace_unlock(), and mount is not (immediately)
> cleaned up.
>
> For example, this causes LTP move_mount02 fail:
> ...
> move_mount02.c:80: TPASS: invalid-from-fd: move_mount() failed as expected: EBADF (9)
> move_mount02.c:80: TPASS: invalid-from-path: move_mount() failed as expected: ENOENT (2)
> move_mount02.c:80: TPASS: invalid-to-fd: move_mount() failed as expected: EBADF (9)
> move_mount02.c:80: TPASS: invalid-to-path: move_mount() failed as expected: ENOENT (2)
> move_mount02.c:80: TPASS: invalid-flags: move_mount() failed as expected: EINVAL (22)
> tst_test.c:1833: TINFO: === Testing on ext3 ===
> tst_test.c:1170: TINFO: Formatting /dev/loop0 with ext3 opts='' extra opts=''
> mke2fs 1.47.2 (1-Jan-2025)
> /dev/loop0 is apparently in use by the system; will not make a filesystem here!
> tst_test.c:1170: TBROK: mkfs.ext3 failed with exit code 1
>
> [...]

Applied to the vfs.fixes branch of the vfs/vfs.git tree.
Patches in the vfs.fixes branch should appear in linux-next soon.

Please report any outstanding bugs that were missed during review in a
new review to the original patch series allowing us to drop it.

It's encouraged to provide Acked-bys and Reviewed-bys even though the
patch has now been applied. If possible patch trailers will be updated.

Note that commit hashes shown below are subject to change due to rebase,
trailer updates or similar. If in doubt, please check the listed branch.

tree: https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
branch: vfs.fixes

[1/1] fs: use namespace_{lock,unlock} in dissolve_on_fput()
https://git.kernel.org/vfs/vfs/c/47a742fd977a