From 878eaddd05d251cefa9632c2b8046833c5eead66 Mon Sep 17 00:00:00 2001 From: Vivek Goyal Date: Mon, 7 Dec 2009 19:37:15 +0100 Subject: cfq-iosched: Do not access cfqq after freeing it Fix a crash during boot reported by Jeff Moyer. Fix the issue of accessing cfqq after freeing it. Reported-by: Jeff Moyer Signed-off-by: Vivek Goyal Reviewed-by: Jeff Moyer Signed-off-by: Jens Axboe --- block/cfq-iosched.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 3815f9789b6a..cfb0b2f5f63d 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -2368,7 +2368,7 @@ static int cfq_dispatch_requests(struct request_queue *q, int force) static void cfq_put_queue(struct cfq_queue *cfqq) { struct cfq_data *cfqd = cfqq->cfqd; - struct cfq_group *cfqg; + struct cfq_group *cfqg, *orig_cfqg; BUG_ON(atomic_read(&cfqq->ref) <= 0); @@ -2379,6 +2379,7 @@ static void cfq_put_queue(struct cfq_queue *cfqq) BUG_ON(rb_first(&cfqq->sort_list)); BUG_ON(cfqq->allocated[READ] + cfqq->allocated[WRITE]); cfqg = cfqq->cfqg; + orig_cfqg = cfqq->orig_cfqg; if (unlikely(cfqd->active_queue == cfqq)) { __cfq_slice_expired(cfqd, cfqq, 0); @@ -2388,8 +2389,8 @@ static void cfq_put_queue(struct cfq_queue *cfqq) BUG_ON(cfq_cfqq_on_rr(cfqq)); kmem_cache_free(cfq_pool, cfqq); cfq_put_cfqg(cfqg); - if (cfqq->orig_cfqg) - cfq_put_cfqg(cfqq->orig_cfqg); + if (orig_cfqg) + cfq_put_cfqg(orig_cfqg); } /* -- cgit v1.2.3