Commit 7c689e63 authored Mar 27, 2013 by Philipp Reisner Committed by Jens Axboe Mar 28, 2013

drbd: fix for deadlock when using automatic split-brain-recovery



With an automatic after split-brain recovery policy of
"after-sb-1pri call-pri-lost-after-sb",
when trying to drbd_set_role() to R_SECONDARY,
we run into a deadlock.

This was first recognized and supposedly fixed by
2009-06-10 "Fixed a deadlock when using automatic split brain recovery when both nodes are"
replacing drbd_set_role() with drbd_change_state() in that code-path,
but the first hunk of that patch forgets to remove the drbd_set_role().

We apparently only ever tested the "two primaries" case.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

parent 193d0153

drivers/block/drbd/drbd_receiver.c

+0 −1

Original line number	Diff line number	Diff line
		@@ -2662,7 +2662,6 @@ static int drbd_asb_recover_1p(struct drbd_conf *mdev) __must_hold(local)
		if (hg == -1 && mdev->state.role == R_PRIMARY) {
		enum drbd_state_rv rv2;

		drbd_set_role(mdev, R_SECONDARY, 0);
		/* drbd_change_state() does not sleep while in SS_IN_TRANSIENT_STATE,
		* we might be here in C_WF_REPORT_PARAMS which is transient.
		* we do not need to wait for the after state change work either. */