RE: [PATCH v2] scsi: ufs: core: fix racing issue during ufshcd_mcq_abort

[hoyoung seo]

> -----Original Message-----
> From: Bart Van Assche <bvanassche@xxxxxxx>
> Sent: Wednesday, November 15, 2023 2:55 AM
> To: SEO HOYOUNG <hy50.seo@xxxxxxxxxxx>; linux-scsi@xxxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx; alim.akhtar@xxxxxxxxxxx; avri.altman@xxxxxxx;
> jejb@xxxxxxxxxxxxx; martin.petersen@xxxxxxxxxx; beanhuo@xxxxxxxxxx;
> kwangwon.min@xxxxxxxxxxx; kwmad.kim@xxxxxxxxxxx; sh425.lee@xxxxxxxxxxx;
> sc.suh@xxxxxxxxxxx; quic_nguyenb@xxxxxxxxxxx; cpgs@xxxxxxxxxxx;
> grant.jung@xxxxxxxxxxx; junwoo80.lee@xxxxxxxxxxx
> Subject: Re: [PATCH v2] scsi: ufs: core: fix racing issue during
> ufshcd_mcq_abort
> 
> On 11/13/23 20:37, SEO HOYOUNG wrote:
> > diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
> > index 9a730a794b66..55f4c0eeda7b 100644
> > --- a/drivers/ufs/core/ufshcd.c
> > +++ b/drivers/ufs/core/ufshcd.c
> > @@ -7574,6 +7574,10 @@ int ufshcd_try_to_abort_task(struct ufs_hba *hba,
> int tag)
> >   		goto out;
> >   	}
> >
> > +	if (!ufshcd_cmd_inflight(lrbp->cmd) ||
> > +	    test_bit(SCMD_STATE_COMPLETE, &lrbp->cmd->state))
> > +		goto out;
> > +
> >   	err = ufshcd_clear_cmd(hba, tag);
> >   	if (err)
> >   		dev_err(hba->dev, "%s: Failed clearing cmd at tag %d,
> err %d\n",
> 
> The UFS driver must not set SCMD_STATE_COMPLETE itself. Only the SCSI core
> is allowed to set that bit.
> 
> Thanks,
> 
> Bart.

Hi,

The test_bit() function just check SCMD_STATE_COMPLETE bit state.
Do not set SCMD_STATE_COMPLETE field. 
This function is also used in ufshcd_mcq_compl_pending_transfer() 
to check the status of cmd.

Thanks.
BRs SEO.