On Fri, Aug 24, 2018 at 09:17:49PM +0200, Greg Kroah-Hartman wrote:

On Fri, Aug 24, 2018 at 10:08:28AM -0700, Roland Dreier wrote:

quoted

quoted

See
<https://lore.kernel.org/lkml/1512686629.18523.217.camel@codethink.co.uk/T/#u (local)>.

Thanks!  I'm not using SGI UV and I'm not using kexec, so I guess I
sidestepped most of those issues.  Greg, I think we need to unrevert
the cpa->pfn change (otherwise the L1TF fix probably gets pretty
messy) and I guess pull in the other patches that Ben mentions.

Ok, so what patch should be reverted?  I'm seeing other reports of
problems all around this same area, but I can't figure out exactly what
to do.

Guenter, any ideas?

I think we'll need to reapply 87e2bd898d3a ("x86/mm/pat: Ensure cpa->pfn only
contains page frame numbers"), and possibly apply d367cef0a7f0 ("x86/mm/pat:
Fix boot crash when 1GB pages are not supported by the CPU"). Both require
conflict resolutions, but they are quite straightforward. I am not sure
about the other EFI patches.

I am going to send the backports as RFT in a minute. Problem is that I don't
have an EFI system at hand and can not test if this fixes the problem
(or maybe introduces a new one), so someone will need to step in and do
those tests.

Guenter