From: Ming Lei ming.lei@redhat.com
[ Upstream commit 19768f80cf23834e65482f1667ff54192d469fee ]
It isn't correct to set set->nr_maps as 3 if g_poll_queues is > 0 since we can change it via configfs for null_blk device created there, so only set it as 3 if active poll_queues is > 0.
Fixes divide zero exception reported by Shinichiro.
Fixes: 2bfdbe8b7ebd ("null_blk: allow zero poll queues") Reported-by: Shinichiro Kawasaki shinichiro.kawasaki@wdc.com Signed-off-by: Ming Lei ming.lei@redhat.com Reviewed-by: Shin'ichiro Kawasaki shinichiro.kawasaki@wdc.com Link: https://lore.kernel.org/r/20211224010831.1521805-1-ming.lei@redhat.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/block/null_blk/main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c index fc1317060db54..e23aac1a83f73 100644 --- a/drivers/block/null_blk/main.c +++ b/drivers/block/null_blk/main.c @@ -1891,7 +1891,7 @@ static int null_init_tag_set(struct nullb *nullb, struct blk_mq_tag_set *set) if (g_shared_tag_bitmap) set->flags |= BLK_MQ_F_TAG_HCTX_SHARED; set->driver_data = nullb; - if (g_poll_queues) + if (poll_queues) set->nr_maps = 3; else set->nr_maps = 1;