5.4-stable review patch. If anyone has any objections, please let me know.
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From: Ilya Dryomov idryomov@gmail.com
commit 3ceccb14f5576e02b81cc8b105ab81f224bd87f6 upstream.
Expanding on the previous commit, assuming that rbd_is_lock_owner() always returns true (i.e. that we are either in RBD_LOCK_STATE_LOCKED or RBD_LOCK_STATE_QUIESCING) if the mapping is exclusive is wrong too. In case ceph_cls_set_cookie() fails, the lock would be temporarily released even if the mapping is exclusive, meaning that we can end up even in RBD_LOCK_STATE_UNLOCKED.
IOW, exclusive mappings are really "just" about disabling automatic lock transitions (as documented in the man page), not about grabbing the lock and holding on to it whatever it takes.
Cc: stable@vger.kernel.org Fixes: 637cd060537d ("rbd: new exclusive lock wait/wake code") Signed-off-by: Ilya Dryomov idryomov@gmail.com Reviewed-by: Dongsheng Yang dongsheng.yang@easystack.cn Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/block/rbd.c | 5 ----- 1 file changed, 5 deletions(-)
--- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -6618,11 +6618,6 @@ static int rbd_add_acquire_lock(struct r return ret; }
- /* - * The lock may have been released by now, unless automatic lock - * transitions are disabled. - */ - rbd_assert(!rbd_dev->opts->exclusive || rbd_is_lock_owner(rbd_dev)); return 0; }