linux-kernel - Re: x86: AMD Zen2 ymm registers rolling back

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Message-ID: <Y/Xp73KJe3c/1jrn@zn.tnic>
Date:   Wed, 22 Feb 2023 11:09:51 +0100
From:   Borislav Petkov <bp@...en8.de>
To:     Andrew Cooper <andrew.cooper3@...rix.com>
Cc:     Tavis Ormandy <taviso@...il.com>, linux-kernel@...r.kernel.org,
        x86@...nel.org
Subject: Re: x86: AMD Zen2 ymm registers rolling back

On Wed, Feb 22, 2023 at 09:38:09AM +0000, Andrew Cooper wrote:
> This sounds suspiciously like an errata which was fixed with a ucode
> update last year.

Yes, it looks like it.

Alternatively, you can try booting with "clearcpuid=xsaves" - that
should take care of your observation too but yeah, you should rather
update your microcode.

HTH.

-- 
Regards/Gruss,
    Boris.

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