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

Joerg Roedel
2021-11-24T16:03:46Z

On Mon, Nov 22, 2021 at 02:51:35PM -0800, Dave Hansen wrote:
> My preference would be that we never have SEV-SNP code in the kernel
> that can panic() the host from guest userspace. If that means waiting
> until there's common guest unmapping infrastructure around, then I think
> we should wait.

Can you elaborate how to crash host kernel from guest user-space? If I
understood correctly it was about crashing host kernel from _host_
user-space.

I think the RMP-fault path in the page-fault handler needs to take the
uaccess exception tables into account before actually causing a panic.
This should solve most of the problems discussed here.

Maybe we also need the previously suggested copy_from/to_guest()
interfaces.

Regards,

--
Jörg Rödel
jroedel@suse.de

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