RE: [PATCH v1 2/7] fpga: dfl: check feature type before parse irq info

[Zhang, Tianfei]

> -----Original Message-----
> From: Wu, Hao <hao.wu@xxxxxxxxx>
> Sent: Wednesday, February 16, 2022 11:35 AM
> To: Zhang, Tianfei <tianfei.zhang@xxxxxxxxx>; trix@xxxxxxxxxx;
> mdf@xxxxxxxxxx; Xu, Yilun <yilun.xu@xxxxxxxxx>; linux-fpga@xxxxxxxxxxxxxxx;
> linux-doc@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Cc: corbet@xxxxxxx
> Subject: Re: [PATCH v1 2/7] fpga: dfl: check feature type before parse irq info
> 
> > Subject: [PATCH v1 2/7] fpga: dfl: check feature type before parse irq
> > info
> >
> > From: Tianfei Zhang <tianfei.zhang@xxxxxxxxx>
> >
> > The feature ID of "Port User Interrupt" and the "PMCI Subsystem" are
> > identical, 0x12, but one is for FME, other is for Port. It should
> > check the feature type While parsing the irq info in
> > parse_feature_irqs().
> >
> > Signed-off-by: Tianfei Zhang <tianfei.zhang@xxxxxxxxx>
> > ---
> >  drivers/fpga/dfl.c | 11 +++++++++++
> >  1 file changed, 11 insertions(+)
> >
> > diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c index
> > 599bb21d86af..26f8cf890700 100644
> > --- a/drivers/fpga/dfl.c
> > +++ b/drivers/fpga/dfl.c
> > @@ -940,9 +940,14 @@ static int parse_feature_irqs(struct
> > build_feature_devs_info *binfo,  {
> >  	void __iomem *base = binfo->ioaddr + ofst;
> >  	unsigned int i, ibase, inr = 0;
> > +	enum dfl_id_type type;
> >  	int virq;
> >  	u64 v;
> >
> > +	type = feature_dev_id_type(binfo->feature_dev);
> > +	if (type >= DFL_ID_MAX)
> > +		return -EINVAL;
> > +
> 
> You don't have to check this, it doesn't allow creating feature dev with type >=
> DFL_ID_MAX.

I agree, I will fix on next version.

> 
> >  	/*
> >  	 * Ideally DFL framework should only read info from DFL header, but
> >  	 * current version DFL only provides mmio resources information for
> > @@ -959,16 +964,22 @@ static int parse_feature_irqs(struct
> > build_feature_devs_info *binfo,
> >  	 */
> >  	switch (fid) {
> >  	case PORT_FEATURE_ID_UINT:
> > +		if (type != PORT_ID)
> > +			break;
> >  		v = readq(base + PORT_UINT_CAP);
> >  		ibase = FIELD_GET(PORT_UINT_CAP_FST_VECT, v);
> >  		inr = FIELD_GET(PORT_UINT_CAP_INT_NUM, v);
> >  		break;
> >  	case PORT_FEATURE_ID_ERROR:
> > +		if (type != PORT_ID)
> > +			break;
> >  		v = readq(base + PORT_ERROR_CAP);
> >  		ibase = FIELD_GET(PORT_ERROR_CAP_INT_VECT, v);
> >  		inr = FIELD_GET(PORT_ERROR_CAP_SUPP_INT, v);
> >  		break;
> >  	case FME_FEATURE_ID_GLOBAL_ERR:
> > +		if (type != FME_ID)
> > +			break;
> >  		v = readq(base + FME_ERROR_CAP);
> >  		ibase = FIELD_GET(FME_ERROR_CAP_INT_VECT, v);
> >  		inr = FIELD_GET(FME_ERROR_CAP_SUPP_INT, v);
> > --
> > 2.17.1