Re: [PATCH v1] scsi: ufs: core: print trs for pending requests in MCQ mode

[Bart Van Assche <bvanassche@xxxxxxx>]

On 3/8/23 21:01, Ziqi Chen wrote:
> +static void ufshcd_print_trs_all(struct ufs_hba *hba, bool pr_prdt)
> +{
> +	const struct ufshcd_lrb *lrbp;
> +	int tag;
> +
> +	for (tag = 0; tag < hba->nutrs; tag++) {
> +		lrbp = &hba->lrb[tag];
> +
> +		if (lrbp->cmd)
> +			ufshcd_print_tr(hba, tag, pr_prdt);
>   	}
>   }

There is a race in this code: lrbp->cmd may be cleared after it has been 
read and before or while ufshcd_print_tr() is in progress. How about 
preventing that race by blk_mq_tagset_busy_iter() to iterate over 
pending SCSI commands?

Thanks,

Bart.