On Tue, Oct 27, 2020 at 11:38:46AM +0100, Borislav Petkov wrote:
> So why are we doing those checks here at all then? I mean, the HV
> can tell us whatever it wants, i.e., make sure those checks pass but
> still report the C-bit at the wrong position. Which means that those
> checks are simply meh.
On Wed, Oct 21, 2020 at 02:39:35PM +0200, Joerg Roedel wrote:
> From: Joerg Roedel
>
> The early #VC handler which doesn't have a GHCB can only handle CPUID
> exit codes. It is needed by the early boot code to handle #VC
> exceptions raised in verify_cpu() and to get the position of the C
> bit.
From: Joerg Roedel
The early #VC handler which doesn't have a GHCB can only handle CPUID
exit codes. It is needed by the early boot code to handle #VC
exceptions raised in verify_cpu() and to get the position of the C
bit.
But the CPUID information comes from the hypervisor, which is untrusted
a
3 matches
Mail list logo