Re: [PATCH v2 2/2] PCI/AER: Check validity of Error Source ID register

["Ilpo Järvinen" <ilpo.jarvinen@linux.intel.com>]

[-- Attachment #1: Type: text/plain, Size: 1445 bytes --]

On Fri, 6 Nov 2026, Lukas Wunner wrote:

> On Fri, Nov 06, 2026 at 05:15:07PM +0000, sashiko-bot@kernel.org wrote:
> > > +++ b/drivers/pci/pcie/aer.c
> > > -	/*
> > > -	 * When bus ID is equal to 0, it might be a bad ID
> > > -	 * reported by Root Port.
> > > -	 */
> > > -	if ((PCI_BUS_NUM(e_info->id) != 0) &&
> > > +	/* Some Root Ports report an invalid Error Source ID */
> > > +	if (e_info->id_valid &&
> > >  	    !(dev->bus->bus_flags & PCI_BUS_FLAGS_NO_AERSID)) {
> > >  		/* Device ID match? */
> > >  		if (e_info->id == pci_dev_id(dev))
> > 
> > [Severity: Medium]
> > As reported by Ilpo Järvinen on v1 [1]
> 
> Hallucination, this was reported by sashiko itself and Ilpo merely confirmed
> sashiko's finding.

I agree. I've no problem with this change after the cases we expect this 
impact are not among the cases sashiko came up so the comment in the 
changelog is enough for me.

> > can treating pci_dev_id(root) == id
> > as unconditionally valid cause a false-positive match on the Root Port and
> > skip searching the subordinate hierarchy when a Root Port at 00:00.0 (such
> > as on DesignWare, Cadence, or Aardvark SoC host bridges) reports 0x0000 for
> > a downstream device error, or when a Root Port at 00:xx.y loses the bus
> > number of a downstream error source at bus:xx.y?
> 
> The commit message addresses this concern, it seems sashiko overlooked that
> paragraph.


-- 
 i.