Re: [PATCH] ia64: Don't call SAL < 3.2 for extended config space

[Jesse Barnes <jbarnes@virtuousgeek.org>]

Ah, the SGI 750.  Brings back memories.

I've dropped the ball on this one though; maybe Tony already picked it
up?  Tony?

Thanks,
Jesse

On Tue, 13 Oct 2009 00:58:08 -0400
spender@grsecurity.net (Brad Spengler) wrote:

> I've confirmed that the below patch (with the syntax fixes already 
> mentioned) resolves the issue on the SGI 750.
> 
> -Brad
> 
> > From: Matthew Wilcox <willy@linux.intel.com>
> > Subject: Require SAL 3.2 in order to do extended config space ops
> > 
> > We had assumed that SAL firmware would return an error if it didn't
> > understand extended config space.  Unfortunately, the SAL on the
> > SGI 750 doesn't do that, it panics the machine.  So, condition the
> > extended PCI config space accesses on SAL revision 3.2.
> > 
> > Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
> > 
> > diff --git a/arch/ia64/pci/pci.c b/arch/ia64/pci/pci.c
> > index 7de76dd..61363cc 100644
> > --- a/arch/ia64/pci/pci.c
> > +++ b/arch/ia64/pci/pci.c
> > @@ -56,10 +56,13 @@ int raw_pci_read(unsigned int seg, unsigned int
> > bus, unsigned int devfn, if ((seg | reg) <= 255) {
> >  		addr = PCI_SAL_ADDRESS(seg, bus, devfn, reg);
> >  		mode = 0;
> > -	} else {
> > +	} else if (sal_revision >= SAL_VERSION_CODE(3,2))
> >  		addr = PCI_SAL_EXT_ADDRESS(seg, bus, devfn, reg);
> >  		mode = 1;
> > +	} else {
> > +		return -EINVAL;
> >  	}
> > +
> >  	result = ia64_sal_pci_config_read(addr, mode, len, &data);
> >  	if (result != 0)
> >  		return -EINVAL;
> > @@ -80,9 +83,11 @@ int raw_pci_write(unsigned int seg, unsigned int
> > bus, unsigned int devfn, if ((seg | reg) <= 255) {
> >  		addr = PCI_SAL_ADDRESS(seg, bus, devfn, reg);
> >  		mode = 0;
> > -	} else {
> > +	} else if (sal_revision >= SAL_VERSION_CODE(3,2))
> >  		addr = PCI_SAL_EXT_ADDRESS(seg, bus, devfn, reg);
> >  		mode = 1;
> > +	} else {
> > +		return -EINVAL;
> >  	}
> >  	result = ia64_sal_pci_config_write(addr, mode, len, value);
> >  	if (result != 0)
> > 
> > -- 
> > Matthew Wilcox				Intel Open Source
> > Technology Centre "Bill, look, we understand that you're interested
> > in selling us this operating system, but compare it to ours.  We
> > can't possibly take such a retrograde step."


-- 
Jesse Barnes, Intel Open Source Technology Center