From: Sagi Grimberg <sagi@xxxxxxxxxxx> [ Upstream commit 0067d4b020ea07a58540acb2c5fcd3364bf326e0 ] In case cpu was unplugged, we need to make sure not to assume that the tags for that cpu are still allocated. so check for null tags when reinitializing a tagset. Reported-by: Yi Zhang <yizhan@xxxxxxxxxx> Signed-off-by: Sagi Grimberg <sagi@xxxxxxxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx> --- block/blk-mq-tag.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index dcf5ce3ba4bf..4bc701b32ce2 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -311,6 +311,9 @@ int blk_mq_reinit_tagset(struct blk_mq_tag_set *set) for (i = 0; i < set->nr_hw_queues; i++) { struct blk_mq_tags *tags = set->tags[i]; + if (!tags) + continue; + for (j = 0; j < tags->nr_tags; j++) { if (!tags->rqs[j]) continue; -- 2.11.0