From: Jan Beulich Date: Mon, 11 Mar 2013 09:39:55 +0000 (+0000) Subject: xen-blkback: fix dispatch_rw_block_io() error path X-Git-Tag: v3.8.6~97 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=e90381b0d45eb96e1963db7ebe27adbc4f599e6f;p=karo-tx-linux.git xen-blkback: fix dispatch_rw_block_io() error path commit 0e5e098ac22dae38f957e951b70d3cf73beff0f7 upstream. Commit 7708992 ("xen/blkback: Seperate the bio allocation and the bio submission") consolidated the pendcnt updates to just a single write, neglecting the fact that the error path relied on it getting set to 1 up front (such that the decrement in __end_block_io_op() would actually drop the count to zero, triggering the necessary cleanup actions). Also remove a misleading and a stale (after said commit) comment. Signed-off-by: Jan Beulich Signed-off-by: Konrad Rzeszutek Wilk Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index 0a952f46f909..ef6d9be037a6 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -1001,13 +1001,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, bio->bi_end_io = end_block_io_op; } - /* - * We set it one so that the last submit_bio does not have to call - * atomic_inc. - */ atomic_set(&pending_req->pendcnt, nbio); - - /* Get a reference count for the disk queue and start sending I/O */ blk_start_plug(&plug); for (i = 0; i < nbio; i++) @@ -1035,6 +1029,7 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif, fail_put_bio: for (i = 0; i < nbio; i++) bio_put(biolist[i]); + atomic_set(&pending_req->pendcnt, 1); __end_block_io_op(pending_req, -EINVAL); msleep(1); /* back off a bit */ return -EIO;