Re: [PATCH RESEND v3 01/13] blk-mq: Change rqs check in blk_mq_free_rqs()

[Hannes Reinecke]

On 9/13/21 5:12 PM, John Garry wrote:
> The original code in commit 24d2f90309b23 ("blk-mq: split out tag
> initialization, support shared tags") would check tags->rqs is non-NULL and
> then dereference tags->rqs[].
>
> Then in commit 2af8cbe30531 ("blk-mq: split tag ->rqs[] into two"), we
> started to dereference tags->static_rqs[], but continued to check non-NULL
> tags->rqs.
>
> Check tags->static_rqs as non-NULL instead, which is more logical.
>
> Signed-off-by: John Garry <john.garry@xxxxxxxxxx>
> Reviewed-by: Ming Lei <ming.lei@xxxxxxxxxx>
> ---
>   block/blk-mq.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/block/blk-mq.c b/block/blk-mq.c
> index 108a352051be..2316ff27c1f5 100644
> --- a/block/blk-mq.c
> +++ b/block/blk-mq.c
> @@ -2340,7 +2340,7 @@ void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
>   {
>   	struct page *page;
>   
> -	if (tags->rqs && set->ops->exit_request) {
> +	if (tags->static_rqs && set->ops->exit_request) {
>   		int i;
>   
>   		for (i = 0; i < tags->nr_tags; i++) {
Reviewed-by: Hannes Reinecke <hare@xxxxxxx>

Cheers,

Hannes
--
Dr. Hannes Reinecke                Kernel Storage Architect
hare@xxxxxxx                              +49 911 74053 688
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