4.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: Sagi Grimberg <[email protected]> [ 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 <[email protected]> Signed-off-by: Sagi Grimberg <[email protected]> Signed-off-by: Jens Axboe <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- block/blk-mq-tag.c | 3 +++ 1 file changed, 3 insertions(+) --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -311,6 +311,9 @@ int blk_mq_reinit_tagset(struct blk_mq_t 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;
