Re: [PATCH v5 3/3] vfio/pci: Decouple PCI_COMMAND_MEMORY bit checks from is_virtfn

[Matthew Rosato]

On 9/22/20 12:40 PM, Alex Williamson wrote:
> On Mon, 21 Sep 2020 08:43:29 -0400
> Matthew Rosato <mjrosato@xxxxxxxxxxxxx> wrote:
>
> > On 9/10/20 10:59 AM, Matthew Rosato wrote:
> > > While it is true that devices with is_virtfn=1 will have a Memory Space
> > > Enable bit that is hard-wired to 0, this is not the only case where we
> > > see this behavior -- For example some bare-metal hypervisors lack
> > > Memory Space Enable bit emulation for devices not setting is_virtfn
> > > (s390). Fix this by instead checking for the newly-added
> > > no_command_memory bit which directly denotes the need for
> > > PCI_COMMAND_MEMORY emulation in vfio.
> > >
> > > Fixes: abafbc551fdd ("vfio-pci: Invalidate mmaps and block MMIO access on disabled memory")
> > > Signed-off-by: Matthew Rosato <mjrosato@xxxxxxxxxxxxx>
> > > Reviewed-by: Niklas Schnelle <schnelle@xxxxxxxxxxxxx>
> > > Reviewed-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
> >
> > Polite ping on this patch as the other 2 have now received maintainer
> > ACKs or reviews.  I'm concerned about this popping up in distros as
> > abafbc551fdd was a CVE fix.  Related, see question from the cover:
> >
> > - Restored the fixes tag to patch 3 (but the other 2 patches are
> >     now pre-reqs -- cc stable 5.8?)
>
> I've got these queued in my local branch which I'll push to next for
> v5.10.  I'm thinking that perhaps the right thing would be to add the
> fixes tag to all three patches, otherwise I could see that the PCI/VF
> change might get picked as a dependency, but not the s390 specific one.
> Does this sound correct to everyone?  Thanks,

Sounds good to me.  Thanks!