Re: [PATCH AUTOSEL 5.15 11/12] x86/barrier: Do not serialize MSR accesses on AMD

From: Sasha Levin
Date: Thu Nov 28 2024 - 10:52:52 EST


On Thu, Nov 28, 2024 at 12:59:24PM +0100, Borislav Petkov wrote:
Hey folks,

On Mon, Jan 15, 2024 at 06:26:56PM -0500, Sasha Levin wrote:
From: "Borislav Petkov (AMD)" <bp@xxxxxxxxx>

[ Upstream commit 04c3024560d3a14acd18d0a51a1d0a89d29b7eb5 ]

AMD does not have the requirement for a synchronization barrier when
acccessing a certain group of MSRs. Do not incur that unnecessary
penalty there.

Erwan just mentioned that this one is not in 6.1 and in 5.15. And I have mails
about it getting picked up by AUTOSEL.

Did the AI reconsider in the meantime?

You've missed the 5.10 mail :)

Pavel objected to it so I've dropped it: https://lore.kernel.org/all/Zbli7QIGVFT8EtO4@sashalap/

--
Thanks,
Sasha