Junichi Nomura <j-nom...@ce.jp.nec.com> writes:

> tags is freed in blk_mq_free_rq_map() and should not be used after that.
> The problem doesn't manifest if CONFIG_CPUMASK_OFFSTACK is false because
> free_cpumask_var() is nop.
>
> tags->cpumask is allocated in blk_mq_init_tags() so it's natural to
> free cpumask in its counter part, blk_mq_free_tags().
>
> Fixes: f26cdc8536ad ("blk-mq: Shared tag enhancements")
> Signed-off-by: Jun'ichi Nomura <j-nom...@ce.jp.nec.com>
> Cc: Keith Busch <keith.bu...@intel.com>
> Cc: Jens Axboe <ax...@fb.com>

Reviewed-by: Jeff Moyer <jmo...@redhat.com>


> ---
>  block/blk-mq-tag.c | 1 +
>  block/blk-mq.c     | 4 +---
>  2 files changed, 2 insertions(+), 3 deletions(-)
>
> diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
> index ed96474..ec2d119 100644
> --- a/block/blk-mq-tag.c
> +++ b/block/blk-mq-tag.c
> @@ -641,6 +641,7 @@ void blk_mq_free_tags(struct blk_mq_tags *tags)
>  {
>       bt_free(&tags->bitmap_tags);
>       bt_free(&tags->breserved_tags);
> +     free_cpumask_var(tags->cpumask);
>       kfree(tags);
>  }
>  
> diff --git a/block/blk-mq.c b/block/blk-mq.c
> index 7785ae9..85f0143 100644
> --- a/block/blk-mq.c
> +++ b/block/blk-mq.c
> @@ -2296,10 +2296,8 @@ void blk_mq_free_tag_set(struct blk_mq_tag_set *set)
>       int i;
>  
>       for (i = 0; i < set->nr_hw_queues; i++) {
> -             if (set->tags[i]) {
> +             if (set->tags[i])
>                       blk_mq_free_rq_map(set, set->tags[i], i);
> -                     free_cpumask_var(set->tags[i]->cpumask);
> -             }
>       }
>  
>       kfree(set->tags);
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to