*** WORK IN PROGRESS ***
If a lease break is received right as a filesystem is being unmounted,
it's possible for cifs_kill_sb() to race with a queued
smb2_cached_lease_break(). Since the cfid is no longer on the
cfids->entries list, close_all_cached_dirs() cannot drop the dentry,
leading to the unmount to report these BUGs:
BUG: Dentry ffff88814f37e358{i=1000000000080,n=/} still in use (2) [unmount of cifs cifs]
VFS: Busy inodes after unmount of cifs (cifs)
------------[ cut here ]------------
kernel BUG at fs/super.c:661!
Flush anything in the cifsiod_wq workqueue in close_all_cached_dirs.
Fixes: ebe98f1447bb ("cifs: enable caching of directories for which a lease is held")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Paul Aurich <paul@xxxxxxxxxxxxxx>
---
fs/smb/client/cached_dir.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/fs/smb/client/cached_dir.c b/fs/smb/client/cached_dir.c
index de1e41abdaf2..931108b3bb4a 100644
--- a/fs/smb/client/cached_dir.c
+++ b/fs/smb/client/cached_dir.c
@@ -482,10 +482,13 @@ void close_all_cached_dirs(struct cifs_sb_info *cifs_sb)
list_for_each_entry(cfid, &cfids->entries, entry) {
dput(cfid->dentry);
cfid->dentry = NULL;
}
}
+
+ /* Flush any pending lease breaks */
+ flush_workqueue(cifsiod_wq);
}
/*
* Invalidate all cached dirs when a TCON has been reset
* due to a session loss.
--
2.45.2
