Re: [PATCH] blk-mq: avoid to iterate over stale request

[Bart Van Assche <bvanassche@xxxxxxx>]

On 9/5/21 23:50, Ming Lei wrote:
> -	if (!rq || !refcount_inc_not_zero(&rq->ref))
> +	if (!rq || rq->tag != bitnr || !refcount_inc_not_zero(&rq->ref))
>   		rq = NULL;

Shouldn't the rq->tag != bitnr test happen after the refcount has been 
incremented since otherwise rq->tag can change after it has been read 
and before the refcount is incremented?

Thanks,

Bart.