From: Ming Lei <ming.lei@redhat.com>
Date: Fri, 24 Dec 2021 09:08:31 +0800
Subject: [PATCH] block: null_blk: only set set->nr_maps as 3 if active
poll_queues is > 0
Git-commit: 19768f80cf23834e65482f1667ff54192d469fee
Patch-mainline: v5.17-rc1
References: jsc#PED-1183
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>
Acked-by: Hannes Reinecke <hare@suse.com>
---
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 6be6ccd4a28f..13004beb48ca 100644
--- a/drivers/block/null_blk/main.c
+++ b/drivers/block/null_blk/main.c
@@ -1892,7 +1892,7 @@ 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;
--
2.35.3