Re: [PATCH v1 1/2] x86/sev: Use per-CPU PSC structure in prep for unaccepted memory support

From: Tom Lendacky
Date: Fri Jul 29 2022 - 15:22:28 EST


On 7/29/22 14:08, Dave Hansen wrote:
On 7/29/22 07:25, Tom Lendacky wrote:
Considering that runtime acceptance is already single-threaded[1] *and*
there's a fallback method, why not just have a single copy of this
guarded by a single lock?

This function is called for more than just memory acceptance. It's also
called for any changes from or to private or shared, which isn't
single-threaded.

I think this tidbit from the changelog threw me off:

Protect the use of the per-CPU structure by disabling interrupts during
memory acceptance.

Could you please revise that to accurately capture the impact of this
change?

Is s/memory acceptance/page state changes/ enough of what you are looking for or something more?

Thanks,
Tom