Commit ce42f191 authored Oct 03, 2006 by Hua Zhong Committed by Linus Torvalds Oct 03, 2006

[PATCH] IDE error handling fixes



In 2.6.15.1 I encountered some IDE crashes when unplugging IDE cables to
emulate disk errors.  Below is a patch against 2.6.16 which I think still
applies.

1.  The first BUG_ON could trigger when a PREFLUSH IO fails (it would
   fail the original barrier request which hasn't been marked REQ_STARTED
   yet).

2. the rq could have been dequeued already (same as 1).

3.  HWGROUP(drive)->rq could be NULL because of the ide_error() several
   lines earlier.

Signed-off-by: Hua Zhong <hzhong@gmail.com>
Cc: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

parent dc844e05

drivers/ide/ide-io.c

+6 −3

Original line number	Diff line number	Diff line
		@@ -59,8 +59,6 @@ static int __ide_end_request(ide_drive_t drive, struct request rq,
		{
		int ret = 1;

		BUG_ON(!blk_rq_started(rq));

		/*
		* if failfast is set on a request, override number of sectors and
		* complete the whole request right now
		@@ -82,6 +80,7 @@ static int __ide_end_request(ide_drive_t drive, struct request rq,

		if (!end_that_request_first(rq, uptodate, nr_sectors)) {
		add_disk_randomness(rq->rq_disk);
		if (!list_empty(&rq->queuelist))
		blkdev_dequeue_request(rq);
		HWGROUP(drive)->rq = NULL;
		end_that_request_last(rq, uptodate);
		@@ -1346,6 +1345,10 @@ static ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error)
		* make sure request is sane
		*/
		rq = HWGROUP(drive)->rq;

		if (!rq)
		goto out;

		HWGROUP(drive)->rq = NULL;

		rq->errors = 0;