From: Ronnie Sahlberg lsahlber@redhat.com
commit 47178c7722ac528ea08aa82c3ef9ffa178962d7a upstream.
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 Acked-by: Paulo Alcantara (SUSE) pc@cjr.nz Cc: stable@vger.kernel.org Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/cifs/cifsfs.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-)
--- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -254,6 +254,9 @@ static void cifs_kill_sb(struct super_bl struct cifs_sb_info *cifs_sb = CIFS_SB(sb); struct cifs_tcon *tcon; struct cached_fid *cfid; + struct rb_root *root = &cifs_sb->tlink_tree; + struct rb_node *node; + struct tcon_link *tlink;
/* * We ned to release all dentries for the cached directories @@ -263,17 +266,21 @@ static void cifs_kill_sb(struct super_bl dput(cifs_sb->root); cifs_sb->root = NULL; } - tcon = cifs_sb_master_tcon(cifs_sb); - if (tcon) { + spin_lock(&cifs_sb->tlink_tree_lock); + node = rb_first(root); + while (node != NULL) { + tlink = rb_entry(node, struct tcon_link, tl_rbnode); + tcon = tlink_tcon(tlink); cfid = &tcon->crfid; mutex_lock(&cfid->fid_mutex); if (cfid->dentry) { - dput(cfid->dentry); cfid->dentry = NULL; } mutex_unlock(&cfid->fid_mutex); + node = rb_next(node); } + spin_unlock(&cifs_sb->tlink_tree_lock);
kill_anon_super(sb); cifs_umount(cifs_sb);