Subject: Re: [PATCH v2] ptp: kvm: Use decrypted memory in confidential guest on x86

From: Jakub Kicinski <[email-masked]>
Date: Mon, 27 Feb 2023 15:40:21 -0800

On Mon, 27 Feb 2023 15:58:19 +0000 Jeremi Piotrowski wrote:
> KVM_HC_CLOCK_PAIRING currently fails inside SEV-SNP guests because the
> guest passes an address to static data to the host. In confidential
> computing the host can't access arbitrary guest memory so handling the
> hypercall runs into an "rmpfault". To make the hypercall work, the guest
> needs to explicitly mark the memory as decrypted. Do that in
> kvm_arch_ptp_init(), but retain the previous behavior for
> non-confidential guests to save us from having to allocate memory.
> 
> Add a new arch-specific function (kvm_arch_ptp_exit()) to free the
> allocation and mark the memory as encrypted again.

# Form letter - net-next is closed

The merge window for v6.3 has begun and therefore net-next is closed
for new drivers, features, code refactoring and optimizations.
We are currently accepting bug fixes only.

Please repost when net-next reopens after Mar 6th.

RFC patches sent for review only are obviously welcome at any time.