Messages in this thread | | | Date | Sat, 31 Jul 2021 09:17:37 +0200 | From | Joerg Roedel <> | Subject | Re: [PATCH 11/12] x86/sev: Handle CLFLUSH MMIO events |
| |
Hi Sean,
On Fri, Jul 30, 2021 at 10:42:30PM +0000, Sean Christopherson wrote: > On Wed, Jul 21, 2021, Joerg Roedel wrote: > This wording can be misread as "the hypervisor is responsible for _all_ cache > management". Maybe just: > > /* > * Ignore CLFLUSHes - the hyperivsor is responsible for cache > * management of emulated MMIO. > */
Right, will update the comment, thanks.
> Side topic, out of curisoity, what's mapping/accessing emulated MMIO as non-UC?
The CLFLUSHes happen when the kexec'ed kernel maps the VGA framebuffer as unencrypted. Initially it is mapped encrypted and before re-mapping the kernel flushes the range from the caches.
I have not investigated why this doesn't happen on the first boot, though.
Regards,
Joerg
| |