locks: allow __break_lease to sleep even when break_time is 0
authorJeff Layton <jlayton@redhat.com>
Tue, 15 Apr 2014 10:17:49 +0000 (06:17 -0400)
committerJeff Layton <jlayton@redhat.com>
Tue, 15 Apr 2014 10:17:49 +0000 (06:17 -0400)
commitf1c6bb2cb8b81013e8979806f8e15e3d53efb96d
tree88d552bbd82ac55b0d9e793b7a09b8a56ee1ab2e
parent55101e2d6ce1c780f6ee8fee5f37306971aac6cd
locks: allow __break_lease to sleep even when break_time is 0

A fl->fl_break_time of 0 has a special meaning to the lease break code
that basically means "never break the lease". knfsd uses this to ensure
that leases don't disappear out from under it.

Unfortunately, the code in __break_lease can end up passing this value
to wait_event_interruptible as a timeout, which prevents it from going
to sleep at all. This makes __break_lease to spin in a tight loop and
causes soft lockups.

Fix this by ensuring that we pass a minimum value of 1 as a timeout
instead.

Cc: <stable@vger.kernel.org>
Cc: J. Bruce Fields <bfields@fieldses.org>
Reported-by: Terry Barnaby <terry1@beam.ltd.uk>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
fs/locks.c