Re: [PATCH] cifs: fix handlecache and multiuser

[Paulo Alcantara <pc@cjr.nz>]

Ronnie Sahlberg <lsahlber@redhat.com> writes:

> In multiuser each individual user has their own tcon structure for the
> share and thus their own handle for a cached directory.
> When we umount such a share we much make sure to release the pinned down dentry
> for each such tcon and not just the master tcon.
>
> Otherwise we will get nasty warnings on umount that dentries are still in use:
> [ 3459.590047] BUG: Dentry 00000000115c6f41{i=12000000019d95,n=/}  still in use\
>  (2) [unmount of cifs cifs]
> ...
> [ 3459.590492] Call Trace:
> [ 3459.590500]  d_walk+0x61/0x2a0
> [ 3459.590518]  ? shrink_lock_dentry.part.0+0xe0/0xe0
> [ 3459.590526]  shrink_dcache_for_umount+0x49/0x110
> [ 3459.590535]  generic_shutdown_super+0x1a/0x110
> [ 3459.590542]  kill_anon_super+0x14/0x30
> [ 3459.590549]  cifs_kill_sb+0xf5/0x104 [cifs]
> [ 3459.590773]  deactivate_locked_super+0x36/0xa0
> [ 3459.590782]  cleanup_mnt+0x131/0x190
> [ 3459.590789]  task_work_run+0x5c/0x90
> [ 3459.590798]  exit_to_user_mode_loop+0x151/0x160
> [ 3459.590809]  exit_to_user_mode_prepare+0x83/0xd0
> [ 3459.590818]  syscall_exit_to_user_mode+0x12/0x30
> [ 3459.590828]  do_syscall_64+0x48/0x90
> [ 3459.590833]  entry_SYSCALL_64_after_hwframe+0x44/0xae
>
> Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
> ---
>  fs/cifs/cifsfs.c | 13 ++++++++++---
>  1 file changed, 10 insertions(+), 3 deletions(-)

Acked-by: Paulo Alcantara (SUSE) <pc@cjr.nz>