md/raid10: call wait_barrier() for each request submitted. (cc13b1d1) · Commits · 戴 / test

wait_barrier() includes a counter, so we must call it precisely once (unless balanced by allow_barrier()) for each request submitted. Since commit block: Introduce new bio_split() in 3.14-rc1, we don't call it for the extra requests generated when we need to split a bio. When this happens the counter goes negative, any resync/recovery will never start, and "mdadm --stop" will hang. Reported-by:

Chris Murphy <lists@colorremedies.com> Fixes: Cc: stable@vger.kernel.org (3.14+) Cc: Kent Overstreet <kmo@daterainc.com> Signed-off-by:

NeilBrown <neilb@suse.de>

drivers/md/raid10.c

+7 −6

Original line number	Diff line number	Diff line
		@@ -1172,6 +1172,13 @@ static void __make_request(struct mddev mddev, struct bio bio)
		int max_sectors;
		int sectors;

		/*
		* Register the new request and wait if the reconstruction
		* thread has put up a bar for new requests.
		* Continue immediately if no resync is active currently.
		*/
		wait_barrier(conf);

		sectors = bio_sectors(bio);
		while (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
		bio->bi_iter.bi_sector < conf->reshape_progress &&
		@@ -1552,12 +1559,6 @@ static void make_request(struct mddev mddev, struct bio bio)

		md_write_start(mddev, bio);

		/*
		* Register the new request and wait if the reconstruction
		* thread has put up a bar for new requests.
		* Continue immediately if no resync is active currently.
		*/
		wait_barrier(conf);

		do {

Admin message