From: Borislav Petkov Date: Mon, 3 Oct 2011 18:28:18 +0000 (-0400) Subject: ide-disk: Fix request requeuing X-Git-Tag: v3.1-rc9~8^2 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=2c8fc867602e385fd2abe76da0b6bda8ed907547;p=linux.git ide-disk: Fix request requeuing Simon Kirby reported that on his RAID setup with idedisk underneath the box OOMs after a couple of days of runtime. Running with CONFIG_DEBUG_KMEMLEAK pointed to idedisk_prep_fn() which unconditionally allocates an ide_cmd struct. However, ide_requeue_and_plug() can be called more than once per request, either from the request issue or the IRQ handler path and do blk_peek_request() ends up in idedisk_prep_fn() repeatedly, allocating a struct ide_cmd everytime and "forgetting" the previous pointer. Make sure the code reuses the old allocated chunk. Reported-and-tested-by: Simon Kirby Cc: [ 39.x, 3.0.x ] Link: http://marc.info/?l=linux-kernel&m=131667641517919 Link: http://lkml.kernel.org/r/20110922072643.GA27232@hostway.ca Signed-off-by: Borislav Petkov Signed-off-by: David S. Miller --- diff --git a/drivers/ide/ide-disk.c b/drivers/ide/ide-disk.c index 274798068a54..16f69be820c7 100644 --- a/drivers/ide/ide-disk.c +++ b/drivers/ide/ide-disk.c @@ -435,7 +435,12 @@ static int idedisk_prep_fn(struct request_queue *q, struct request *rq) if (!(rq->cmd_flags & REQ_FLUSH)) return BLKPREP_OK; - cmd = kzalloc(sizeof(*cmd), GFP_ATOMIC); + if (rq->special) { + cmd = rq->special; + memset(cmd, 0, sizeof(*cmd)); + } else { + cmd = kzalloc(sizeof(*cmd), GFP_ATOMIC); + } /* FIXME: map struct ide_taskfile on rq->cmd[] */ BUG_ON(cmd == NULL);