Re: [PATCH RFC 0/2] x86/PCI: SiS PIRQ router updates

[Maciej W. Rozycki]

On Sat, 3 Jul 2021, Maciej W. Rozycki wrote:

> > >   Nikolai, can you please give it a hit with the extra debug patch as
> > > requested in my other message?
> > 
> > With
> > linux-x86-pirq-router-sis85c503.diff applied
> > linux-x86-pirq-router-sis85c497.diff applied
> > and DEBUG 1 in arch/x86/include/asm/pci_x86.h
> > here is new log:
> > 
> > https://pastebin.com/n3udQgcq
> > 
> > My feeling is that something went a bit wrong because:
> > 
> > 8139too 0000:00:0d.0: can't route interrupt
> 
>  More important is actually the previous line:
> 
> PCI: Attempting to find IRQ router for [0000:0000]
> 
> meaning that the PIRQ structure defined by the BIOS has not specified the 
> vendor:device ID pair for the router [1039:0496] which we match against.

 So it's actually both the vendor:device ID pair and the bus address that 
matter here.  I've now posted a patch I am fairly sure about that combined 
with the earlier changes it will fix your issue.  I have verified it in a 
simulated environment where the PIRQ routing table has an invalid vendor 
ID given, with correct results produced:

PCI: Attempting to find IRQ router for [0000:0000]
PCI: Trying IRQ router for [8086:1250]
PCI: Trying IRQ router for [8086:7000]
pci 0000:00:07.0: SIO/PIIX/ICH IRQ router [8086:7000]

 Please let me know of the outcome.

  Maciej