raid5: check faulty flag for array status during recovery. (16d9cfab) · Commits · 戴 / test

When we have more than 1 drive failure, it's possible we start rebuild one drive while leaving another faulty drive in array. To determine whether array will be optimal after building, current code only check whether a drive is missing, which could potentially lead to data corruption. This patch is to add checking Faulty flag. Signed-off-by:

NeilBrown <neilb@suse.de>

drivers/md/raid5.c

+9 −4

Original line number	Diff line number	Diff line
		@@ -5121,12 +5121,17 @@ static inline sector_t sync_request(struct mddev *mddev, sector_t sector_nr, int
		schedule_timeout_uninterruptible(1);
		}
		/* Need to check if array will still be degraded after recovery/resync
		* We don't need to check the 'failed' flag as when that gets set,
		* recovery aborts.
		* Note in case of > 1 drive failures it's possible we're rebuilding
		* one drive while leaving another faulty drive in array.
		*/
		for (i = 0; i < conf->raid_disks; i++)
		if (conf->disks[i].rdev == NULL)
		rcu_read_lock();
		for (i = 0; i < conf->raid_disks; i++) {
		struct md_rdev *rdev = ACCESS_ONCE(conf->disks[i].rdev);

		if (rdev == NULL \|\| test_bit(Faulty, &rdev->flags))
		still_degraded = 1;
		}
		rcu_read_unlock();

		bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, still_degraded);

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