Commit 7aa8dfa4 authored by Paolo Valente's avatar Paolo Valente Committed by Greg Kroah-Hartman

block, bfq: handle NULL return value by bfq_init_rq()

[ Upstream commit fd03177c ]

As reported in [1], the call bfq_init_rq(rq) may return NULL in case
of OOM (in particular, if rq->elv.icq is NULL because memory
allocation failed in failed in ioc_create_icq()).

This commit handles this circumstance.

[1] https://lkml.org/lkml/2019/7/22/824

Cc: Hsin-Yi Wang <hsinyi@google.com>
Cc: Nicolas Boichat <drinkcat@chromium.org>
Cc: Doug Anderson <dianders@chromium.org>
Reported-by: default avatarGuenter Roeck <linux@roeck-us.net>
Reported-by: default avatarHsin-Yi Wang <hsinyi@google.com>
Reviewed-by: default avatarGuenter Roeck <linux@roeck-us.net>
Signed-off-by: default avatarPaolo Valente <paolo.valente@linaro.org>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
parent fa6f4687
......@@ -1886,9 +1886,14 @@ static void bfq_request_merged(struct request_queue *q, struct request *req,
blk_rq_pos(container_of(rb_prev(&req->rb_node),
struct request, rb_node))) {
struct bfq_queue *bfqq = bfq_init_rq(req);
struct bfq_data *bfqd = bfqq->bfqd;
struct bfq_data *bfqd;
struct request *prev, *next_rq;
if (!bfqq)
return;
bfqd = bfqq->bfqd;
/* Reposition request in its sort_list */
elv_rb_del(&bfqq->sort_list, req);
elv_rb_add(&bfqq->sort_list, req);
......@@ -1930,6 +1935,9 @@ static void bfq_requests_merged(struct request_queue *q, struct request *rq,
struct bfq_queue *bfqq = bfq_init_rq(rq),
*next_bfqq = bfq_init_rq(next);
if (!bfqq)
return;
/*
* If next and rq belong to the same bfq_queue and next is older
* than rq, then reposition rq in the fifo (by substituting next
......@@ -4590,12 +4598,12 @@ static void bfq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,
spin_lock_irq(&bfqd->lock);
bfqq = bfq_init_rq(rq);
if (at_head || blk_rq_is_passthrough(rq)) {
if (!bfqq || at_head || blk_rq_is_passthrough(rq)) {
if (at_head)
list_add(&rq->queuelist, &bfqd->dispatch);
else
list_add_tail(&rq->queuelist, &bfqd->dispatch);
} else { /* bfqq is assumed to be non null here */
} else {
idle_timer_disabled = __bfq_insert_request(bfqd, rq);
/*
* Update bfqq, because, if a queue merge has occurred
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment