Re: [PATCH v5 4/6] target/i386: Add feature that indicates WRMSR to BASE reg is non-serializing

"Moger, Babu" <bmoger@xxxxxxx> · Thu, 20 Feb 2025 18:45:21 -0600

Hi Zhao,

On 2/20/2025 6:00 AM, Zhao Liu wrote:
On Thu, Feb 06, 2025 at 01:28:37PM -0600, Babu Moger wrote:
Date: Thu, 6 Feb 2025 13:28:37 -0600
From: Babu Moger <babu.moger@xxxxxxx>
Subject: [PATCH v5 4/6] target/i386: Add feature that indicates WRMSR to
  BASE reg is non-serializing
X-Mailer: git-send-email 2.34.1

Add the CPUID bit indicates that a WRMSR to MSR_FS_BASE, MSR_GS_BASE, or
MSR_KERNEL_GS_BASE is non-serializing.

CPUID_Fn80000021_EAX
Bit    Feature description
1      FsGsKernelGsBaseNonSerializing.
        WRMSR to FS_BASE, GS_BASE and KernelGSbase are non-serializing.

Link: https://www.amd.com/content/dam/amd/en/documents/epyc-technical-docs/programmer-references/57238.zip
Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
Reviewed-by: Maksim Davydov <davydov-max@xxxxxxxxxxxxxx>
---
  target/i386/cpu.c | 2 +-
  target/i386/cpu.h | 2 ++
  2 files changed, 3 insertions(+), 1 deletion(-)

Reviewed-by: Zhao Liu <zhao1.liu@xxxxxxxxx>

Thank you,
Babu