[PATCH v2 2/4] powerpc/powernv: Fix stale PE primary bus

[Michael Ellerman]

On Fri, 2016-02-12 at 17:09 +1100, Gavin Shan wrote:

> On Fri, Feb 12, 2016 at 05:02:46PM +1100, Andrew Donnellan wrote:

> > On 09/02/16 15:50, Gavin Shan wrote:

> > > When PCI bus is unplugged during full hotplug for EEH recovery,
> > > the platform PE instance (struct pnv_ioda_pe) isn't released and
> > > it dereferences the stale PCI bus that has been released. It leads
> > > to kernel crash when referring to the stale PCI bus.
> > > 
> > > This fixes the issue by correcting the PE's primary bus when it's
> > > oneline at plugging time, in pnv_pci_dma_bus_setup() which is to
> > > be called by pcibios_fixup_bus().
> > > 
> > > Reported-by: Andrew Donnellan <andrew.donnellan at au1.ibm.com>
> > > Reported-by: Pradipta Ghosh <pradghos at in.ibm.com>
> > > Signed-off-by: Gavin Shan <gwshan at linux.vnet.ibm.com>
> > > Tested-by: Andrew Donnellan <andrew.donnellan at au1.ibm.com>
> > 
> > I realise this has already been merged, but the following was found by
> > Coverity:
> > 

> > > +void pnv_pci_dma_bus_setup(struct pci_bus *bus)
> > > +{
> > > +	struct pci_controller *hose = bus->sysdata;
> > > +	struct pnv_phb *phb = hose->private_data;
> > > +	struct pnv_ioda_pe *pe;
> > > +
> > > +	list_for_each_entry(pe, &phb->ioda.pe_list, list) {
> > > +		if (!(pe->flags | (PNV_IODA_PE_BUS | PNV_IODA_PE_BUS_ALL)))
> > > +			continue;
> > 
> > This condition is always false. I think the first "|" is supposed to be "&".
> > 
> 
> Yeah, that should be "&". I think the problem isn't found when doing
> testing in non-SRIOV environment. Thanks for pointing it out.
> 
> Michael, please let me know if I need send a follow-up revision to
> correct this one? I found the first two patches have been put into
> linux-next branch. I think we probably just need repost the correct
> version for this one only.

As it happens I needed to rebase my fixes branch anyway, so I've updated it and
rebased. No further action required :)

cheers