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

[Lukas Wunner <lukas@wunner.de>]

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.

> 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.

Thanks,

Lukas