From mboxrd@z Thu Jan 1 00:00:00 1970 From: NeilBrown Subject: [PATCH 003 of 4] md: Make sure the events count in an md array never returns to zero. Date: Tue, 23 Jan 2007 11:26:56 +1100 Message-ID: <1070123002656.29477@suse.de> References: <20070123112437.29357.patches@notabene> Return-path: Sender: linux-kernel-owner@vger.kernel.org To: Andrew Morton Cc: linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-raid.ids Now that we sometimes step the array events count backwards (when transitioning dirty->clean where nothing else interesting has happened - so that we don't need to write to spares all the time), it is possible for the event count to return to zero, which is potentially confusing and triggers and MD_BUG. We could possibly remove the MD_BUG, but is just as easy, and probably safer, to make sure we never return to zero. Signed-off-by: Neil Brown ### Diffstat output ./drivers/md/md.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff .prev/drivers/md/md.c ./drivers/md/md.c --- .prev/drivers/md/md.c 2007-01-23 11:13:44.000000000 +1100 +++ ./drivers/md/md.c 2007-01-23 11:23:58.000000000 +1100 @@ -1633,7 +1633,8 @@ repeat: * and 'events' is odd, we can roll back to the previous clean state */ if (nospares && (mddev->in_sync && mddev->recovery_cp == MaxSector) - && (mddev->events & 1)) + && (mddev->events & 1) + && mddev->events != 1) mddev->events--; else { /* otherwise we have to go forward and ... */