[v2,1/2] scsi: ufs: Cleanup completed request without interrupt notification
diff mbox series

Message ID 20200811141859.27399-2-huobean@gmail.com
State Mainlined
Commit b10178ee7fa88b68a9e8adc06534d2605cb0ec23
Headers show
Series
  • scsi: ufs: two fixups of ufshcd_abort()
Related show

Commit Message

Bean Huo Aug. 11, 2020, 2:18 p.m. UTC
From: Stanley Chu <stanley.chu@mediatek.com>

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@mediatek.com>
Reviewed-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Bean Huo <beanhuo@micron.com>
---
 drivers/scsi/ufs/ufshcd.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Stanley Chu Aug. 12, 2020, 12:47 p.m. UTC | #1
Hi Avri, Bean,

On Tue, 2020-08-11 at 16:18 +0200, Bean Huo wrote:
> From: Stanley Chu <stanley.chu@mediatek.com>
> 
> 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@mediatek.com>
> Reviewed-by: Can Guo <cang@codeaurora.org>
> Signed-off-by: Bean Huo <beanhuo@micron.com>

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);
Bean Huo Aug. 12, 2020, 2:42 p.m. UTC | #2
On Wed, 2020-08-12 at 20:47 +0800, Stanley Chu wrote:
> Hi Avri, Bean,
> 
> On Tue, 2020-08-11 at 16:18 +0200, Bean Huo wrote:
> > From: Stanley Chu <stanley.chu@mediatek.com>
> > 
> > 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@mediatek.com>
> > Reviewed-by: Can Guo <cang@codeaurora.org>
> > Signed-off-by: Bean Huo <beanhuo@micron.com>
> 
> 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
do I need to re-send the patchset to add your Acked-by tag?
or you will sign your acked-by statement and append this patch?

Thanks,
Bean

> 
> 
> Hi Avri,
> 
> Please correct above description if required.
> Thanks for your review! : )
> 
> 
> Thanks,
> 
> Stanley Chu
>
Avri Altman Aug. 13, 2020, 11:05 a.m. UTC | #3
> >
> > Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
> > Reviewed-by: Can Guo <cang@codeaurora.org>
> > Signed-off-by: Bean Huo <beanhuo@micron.com>
Acked-by: Avri Altman <avri.altman@wdc.com>

Patch
diff mbox series

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);