Re: [PATCH 00/31 v2] PTI support for x86_32

[Joerg Roedel]

Hi Juergen,

On Fri, Feb 09, 2018 at 01:11:42PM +0100, Juergen Gross wrote:
> On 09/02/18 10:25, Joerg Roedel wrote:
> > XENPV is also untested from my side, but I added checks to
> > not do the stack switches in the entry-code when XENPV is
> > enabled, so hopefully it works. But someone should test it,
> > of course.
> 
> That's unfortunate. 32 bit XENPV kernel is vulnerable to Meltdown, too.
> I'll have a look whether 32 bit XENPV is still working, though.
> 
> Adding support for KPTI with Xen PV should probably be done later. :-)

Not sure how much is missing to make it work there, one point is
certainly to write the right stack into tss.sp0 for xenpv on 32bit. This
write has a check to only happen for !xenpv.

But let's first test the code as-is on XENPV and see if it still boots
:)


Thanks,

	Joerg