linux-kernel - Re: [PATCH v4 09/15] KVM: SEV: sync FPU and AVX state at LAUNCH_UPDATE

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <56958bb8-1b4e-4691-8d81-d8e5846a3b06@intel.com>
Date: Tue, 19 Mar 2024 13:07:39 -0700
From: Dave Hansen <dave.hansen@...el.com>
To: Paolo Bonzini <pbonzini@...hat.com>, linux-kernel@...r.kernel.org,
 kvm@...r.kernel.org
Cc: michael.roth@....com, isaku.yamahata@...el.com, seanjc@...gle.com,
 Dave Hansen <dave.hansen@...ux.intel.com>
Subject: Re: [PATCH v4 09/15] KVM: SEV: sync FPU and AVX state at
 LAUNCH_UPDATE_VMSA time

On 3/18/24 16:33, Paolo Bonzini wrote:
> Since the XSAVE state for AVX is the first, it does not need the
> compacted-state handling of get_xsave_addr().  However, there are other
> parts of XSAVE state in the VMSA that currently are not handled, and
> the validation logic of get_xsave_addr() is pointless to duplicate
> in KVM, so move get_xsave_addr() to public FPU API; it is really just
> a facility to operate on XSAVE state and does not expose any internal
> details of arch/x86/kernel/fpu.

We don't want to grow _too_ many users of get_xsave_addr() since it's
hard to use it right.  But this seems to be a legitimate user.

Acked-by: Dave Hansen <dave.hansen@...ux.intel.com>