Re: [PATCH v3 04/10] x86/fpu/xstate: Correct guest fpstate size calculation
From: Dave Hansen
Date: Fri Mar 07 2025 - 12:54:17 EST
On 3/7/25 08:41, Chao Gao wrote:
> Note that this issue does not cause any functional problems because the
> guest fpstate is allocated using vmalloc(), which aligns the size to a
> full page, providing enough space for all existing supervisor components.
> On Emerald Rapids CPUs, the guest fpstate after this correction is ~2880
> bytes.
How about we move up the fpstate pointers at allocation time so they
just scrape the end of the vmalloc buffer? Basically, move the
page-alignment padding to the beginning of the first page instead of the
end of the last page.