diff options
| author | Yu Kuai <yukuai3@huawei.com> | 2022-05-13 10:35:06 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2022-05-16 11:39:20 -0600 |
| commit | 181490d5321806e537dc5386db5ea640b826bf78 (patch) | |
| tree | 863c51bbcc79a13cda5dbfda4106050ed2bf3a36 /block | |
| parent | a3e7689bfaae031177ebbb257d5a704b47236044 (diff) | |
| download | linux-181490d5321806e537dc5386db5ea640b826bf78.tar.gz | |
block, bfq: protect 'bfqd->queued' by 'bfqd->lock'
If bfq_schedule_dispatch() is called from bfq_idle_slice_timer_body(), then 'bfqd->queued' is read without holding 'bfqd->lock'. This is wrong since it can be wrote concurrently. Fix the problem by holding 'bfqd->lock' in such case. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20220513023507.2625717-2-yukuai3@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block')
| -rw-r--r-- | block/bfq-iosched.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c index e47c75f1fa0f..62180dda6bf9 100644 --- a/block/bfq-iosched.c +++ b/block/bfq-iosched.c @@ -456,6 +456,8 @@ static struct bfq_io_cq *bfq_bic_lookup(struct request_queue *q) */ void bfq_schedule_dispatch(struct bfq_data *bfqd) { + lockdep_assert_held(&bfqd->lock); + if (bfqd->queued != 0) { bfq_log(bfqd, "schedule dispatch"); blk_mq_run_hw_queues(bfqd->queue, true); @@ -6892,8 +6894,8 @@ bfq_idle_slice_timer_body(struct bfq_data *bfqd, struct bfq_queue *bfqq) bfq_bfqq_expire(bfqd, bfqq, true, reason); schedule_dispatch: - spin_unlock_irqrestore(&bfqd->lock, flags); bfq_schedule_dispatch(bfqd); + spin_unlock_irqrestore(&bfqd->lock, flags); } /* |