| Message ID | 20190807172111.4718-2-paolo.valente@linaro.org |
|---|---|
| State | Accepted |
| Commit | fd03177c33b287c6541f4048f1d67b7b45a1abc9 |
| Headers | show |
| Series | handle NULL return value by bfq_init_rq() | expand |
On 8/7/19 10:21 AM, Paolo Valente wrote: > 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 > > Reported-by: Guenter Roeck <linux@roeck-us.net> > Reported-by: Hsin-Yi Wang <hsinyi@google.com> > Cc: Hsin-Yi Wang <hsinyi@google.com> > Cc: Nicolas Boichat <drinkcat@chromium.org> > Cc: Doug Anderson <dianders@chromium.org> > Signed-off-by: Paolo Valente <paolo.valente@linaro.org> Reviewed-by: Guenter Roeck <linux@roeck-us.net> > --- > block/bfq-iosched.c | 14 +++++++++++--- > 1 file changed, 11 insertions(+), 3 deletions(-) > > diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c > index 586fcfe227ea..32686300d89b 100644 > --- a/block/bfq-iosched.c > +++ b/block/bfq-iosched.c > @@ -2250,9 +2250,14 @@ 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); > @@ -2299,6 +2304,9 @@ 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 > @@ -5436,12 +5444,12 @@ 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 >
diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c index 586fcfe227ea..32686300d89b 100644 --- a/block/bfq-iosched.c +++ b/block/bfq-iosched.c @@ -2250,9 +2250,14 @@ 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); @@ -2299,6 +2304,9 @@ 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 @@ -5436,12 +5444,12 @@ 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
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 Reported-by: Guenter Roeck <linux@roeck-us.net> Reported-by: Hsin-Yi Wang <hsinyi@google.com> Cc: Hsin-Yi Wang <hsinyi@google.com> Cc: Nicolas Boichat <drinkcat@chromium.org> Cc: Doug Anderson <dianders@chromium.org> Signed-off-by: Paolo Valente <paolo.valente@linaro.org> --- block/bfq-iosched.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) -- 2.20.1