Re: [PATCH Part2 v5 00/45] Add AMD Secure Nested Paging (SEV-SNP) Hypervisor Support

From: Borislav Petkov
Date: Tue Nov 23 2021 - 02:18:40 EST

On Mon, Nov 22, 2021 at 02:51:35PM -0800, Dave Hansen wrote:
> By "supporting", do you mean doing something functional? I don't really
> care if ptrace() to guest private memory returns -EINVAL or whatever.
> The most important thing is not crashing the host.
> Also, as Sean mentioned, this isn't really about ptrace() itself. It's
> really about ensuring that no kernel or devices accesses to guest
> private memory can induce bad behavior.

I keep repeating this suggestion of mine that we should treat
guest-private pages as hw-poisoned pages which have experienced a
uncorrectable error in the past.

mm already knows how to stay away from those.