Re: [PATCH v2 1/2] scsi: ufs: Cleanup completed request without interrupt notification

From: Stanley Chu
Date: Wed Aug 12 2020 - 08:48:01 EST


Hi Avri, Bean,

On Tue, 2020-08-11 at 16:18 +0200, Bean Huo wrote:
> From: Stanley Chu <stanley.chu@xxxxxxxxxxxx>
>
> If somehow no interrupt notification is raised for a completed request
> and its doorbell bit is cleared by host, UFS driver needs to cleanup
> its outstanding bit in ufshcd_abort(). Otherwise, system may behave
> abnormally by below flow:
>
> After ufshcd_abort() returns, this request will be requeued by SCSI
> layer with its outstanding bit set. Any future completed request
> will trigger ufshcd_transfer_req_compl() to handle all "completed
> outstanding bits". In this time, the "abnormal outstanding bit"
> will be detected and the "requeued request" will be chosen to execute
> request post-processing flow. This is wrong because this request is
> still "alive".
>
> Signed-off-by: Stanley Chu <stanley.chu@xxxxxxxxxxxx>
> Reviewed-by: Can Guo <cang@xxxxxxxxxxxxxx>
> Signed-off-by: Bean Huo <beanhuo@xxxxxxxxxx>

Thanks Bean's patch integration.

Like Avri's comment in https://patchwork.kernel.org/patch/11683381/
I think you could add Acked-by tag from Avri.



Hi Avri,

Please correct above description if required.
Thanks for your review! : )


Thanks,

Stanley Chu

> ---
> drivers/scsi/ufs/ufshcd.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index 307622284239..66fe814c8725 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -6492,7 +6492,7 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
> /* command completed already */
> dev_err(hba->dev, "%s: cmd at tag %d successfully cleared from DB.\n",
> __func__, tag);
> - goto out;
> + goto cleanup;
> } else {
> dev_err(hba->dev,
> "%s: no response from device. tag = %d, err %d\n",
> @@ -6526,6 +6526,7 @@ static int ufshcd_abort(struct scsi_cmnd *cmd)
> goto out;
> }
>
> +cleanup:
> scsi_dma_unmap(cmd);
>
> spin_lock_irqsave(host->host_lock, flags);