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
The test makes number of move_mount() calls but these are all designed to fail
with specific errno. Even after test, 'losetup -d' can't detach loop device.
Define a new guard for dissolve_on_fput, that will use namespace_{lock,unlock}.
Fixes: b73ec10a4587 ("fs: add fastpath for dissolve_on_fput()")
Signed-off-by: Jan Stancek <jstancek@xxxxxxxxxx>
---
fs/namespace.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/fs/namespace.c b/fs/namespace.c
index 14935a0500a2..ee1fdb3baee0 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1830,6 +1830,8 @@ static inline void namespace_lock(void)
down_write(&namespace_sem);
}
+DEFINE_GUARD(namespace_locked, struct rw_semaphore *, namespace_lock(), namespace_unlock())
+
enum umount_tree_flags {
UMOUNT_SYNC = 1,
UMOUNT_PROPAGATE = 2,
@@ -2383,7 +2385,7 @@ void dissolve_on_fput(struct vfsmount *mnt)
return;
}
- scoped_guard(rwsem_write, &namespace_sem) {
+ scoped_guard(namespace_locked, &namespace_sem) {
ns = m->mnt_ns;
if (!must_dissolve(ns))
return;
--
2.43.5
