From: Jonathan Brassow Date: Tue, 27 Feb 2018 20:58:59 +0000 (+0100) Subject: dm raid: fix incorrect sync_ratio when degraded X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=da1e148803e0b98961599b0295418bb7a8fc79f3;p=openwrt%2Fstaging%2Fblogic.git dm raid: fix incorrect sync_ratio when degraded Upstream commit 4102d9de6d375 ("dm raid: fix rs_get_progress() synchronization state/ratio") in combination with commit 7c29744ecce ("dm raid: simplify rs_get_progress()") introduced a regression by incorrectly reporting a sync_ratio of 0 for degraded raid sets. This caused lvm2 to fail to repair raid legs automatically. Fix by identifying the degraded state by checking the MD_RECOVERY_INTR flag and returning mddev->recovery_cp in case it is set. MD sets recovery = [ MD_RECOVERY_RECOVER MD_RECOVERY_INTR MD_RECOVERY_NEEDED ] when a RAID member fails. It then shuts down any sync thread that is running and leaves us with all MD_RECOVERY_* flags cleared. The bug occurs if a status is requested in the short time it takes to shut down any sync thread and clear the flags, because we were keying in on the MD_RECOVERY_NEEDED - understanding it to be the initial phase of a “recover” sync thread. However, this is an incorrect interpretation if MD_RECOVERY_INTR is also set. This also explains why the bug only happened when automatic repair was enabled and not a normal ‘manual’ method. It is impossible to react quick enough to hit the problematic window without it being automated. Fix passes automatic repair tests. Fixes: 7c29744ecce ("dm raid: simplify rs_get_progress()") Signed-off-by: Jonathan Brassow Signed-off-by: Heinz Mauelshagen Signed-off-by: Mike Snitzer --- diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c index 7ef469e902c6..c1d1034ff7b7 100644 --- a/drivers/md/dm-raid.c +++ b/drivers/md/dm-raid.c @@ -3408,9 +3408,10 @@ static sector_t rs_get_progress(struct raid_set *rs, unsigned long recovery, set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags); } else { - if (test_bit(MD_RECOVERY_NEEDED, &recovery) || - test_bit(MD_RECOVERY_RESHAPE, &recovery) || - test_bit(MD_RECOVERY_RUNNING, &recovery)) + if (!test_bit(MD_RECOVERY_INTR, &recovery) && + (test_bit(MD_RECOVERY_NEEDED, &recovery) || + test_bit(MD_RECOVERY_RESHAPE, &recovery) || + test_bit(MD_RECOVERY_RUNNING, &recovery))) r = mddev->curr_resync_completed; else r = mddev->recovery_cp;