locks: allow __break_lease to sleep even when break_time is 0
authorJeff Layton <jlayton@redhat.com>
Tue, 15 Apr 2014 12:44:12 +0000 (08:44 -0400)
committerJ. Bruce Fields <bfields@redhat.com>
Fri, 18 Apr 2014 12:34:30 +0000 (14:34 +0200)
commit4991a628a789dc5954e98e79476d9808812292ec
treece9363e49c9406382a585639ad1a160ce9705d62
parentc9eaa447e77efe77b7fa4c953bd62de8297fd6c5
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 causes __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>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
fs/locks.c