From 18d8217bc441630c3c5ec7416c5a65c69e8a0979 Mon Sep 17 00:00:00 2001 From: Ed Cashin Date: Thu, 10 Sep 2009 22:30:47 +0200 Subject: [PATCH] aoe: end barrier bios with EOPNOTSUPP BugLink: http://bugzilla.kernel.org/show_bug.cgi?id=13942 Bruno Premont noticed that aoe throws a BUG during umount of an XFS in 2.6.31: [ 5259.349897] aoe: bi_io_vec is NULL [ 5259.349940] ------------[ cut here ]------------ [ 5259.349958] kernel BUG at /usr/src/linux-2.6/drivers/block/aoe/aoeblk.c:177! [ 5259.349990] invalid opcode: 0000 [#1] The bio in question is a barrier. Jens Axboe suggested that such bios need to be recognized and ended with -EOPNOTSUPP by any driver that provides its own ->make_request_fn handler and does not handle barriers. In testing the changes below eliminate the BUG. (Better would be real barrier support, something that Ed says he'll add for later in the .32 cycle. For now, this at least gets rid of a bug with crashing on an empty barrier. Jens) Signed-off-by: Ed L. Cashin Signed-off-by: Jens Axboe --- drivers/block/aoe/aoeblk.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/block/aoe/aoeblk.c b/drivers/block/aoe/aoeblk.c index 1e15889c4b98..bf7ceba18788 100644 --- a/drivers/block/aoe/aoeblk.c +++ b/drivers/block/aoe/aoeblk.c @@ -172,6 +172,9 @@ aoeblk_make_request(struct request_queue *q, struct bio *bio) BUG(); bio_endio(bio, -ENXIO); return 0; + } else if (bio_rw_flagged(bio, BIO_RW_BARRIER)) { + bio_endio(bio, -EOPNOTSUPP); + return 0; } else if (bio->bi_io_vec == NULL) { printk(KERN_ERR "aoe: bi_io_vec is NULL\n"); BUG();