[PATCH] PCI: aardvark: Indicate error in 'val' when config read fails

[Pali Rohár]

On Tuesday 07 July 2020 14:53:11 Lorenzo Pieralisi wrote:
> On Fri, Jun 19, 2020 at 12:56:18PM +0200, Pali Rohár wrote:
> > Hello Lorenzo! Could you please review this patch?
> > 
> > On Monday 01 June 2020 15:03:15 Pali Rohár wrote:
> > > Most callers of config read do not check for return value. But most of the
> > > ones that do, checks for error indication in 'val' variable.
> > > 
> > > This patch updates error handling in advk_pcie_rd_conf() function. If PIO
> > > transfer fails then 'val' variable is set to 0xffffffff which indicates
> > > failture.
> > > 
> > > Signed-off-by: Pali Rohár <pali at kernel.org>
> > 
> > I should add credit for Bjorn as he found this issue
> 
> Could you provide a lore archive link to the relevant
> discussion please ? I will apply it then.

Hello Lorenzo! Here is link to the Bjorn's email:
https://lore.kernel.org/linux-pci/20200528162604.GA323482@bjorn-Precision-5520/

> Lorenzo
> 
> > Reported-by: Bjorn Helgaas <helgaas at kernel.org>
> > 
> > > ---
> > >  drivers/pci/controller/pci-aardvark.c | 4 +++-
> > >  1 file changed, 3 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c
> > > index 53a4cfd7d377..783a7f1f2c44 100644
> > > --- a/drivers/pci/controller/pci-aardvark.c
> > > +++ b/drivers/pci/controller/pci-aardvark.c
> > > @@ -691,8 +691,10 @@ static int advk_pcie_rd_conf(struct pci_bus *bus, u32 devfn,
> > >  	advk_writel(pcie, 1, PIO_START);
> > >  
> > >  	ret = advk_pcie_wait_pio(pcie);
> > > -	if (ret < 0)
> > > +	if (ret < 0) {
> > > +		*val = 0xffffffff;
> > >  		return PCIBIOS_SET_FAILED;
> > > +	}
> > >  
> > >  	advk_pcie_check_pio_status(pcie);
> > >  
> > > -- 
> > > 2.20.1
> > >