Re: x86: AMD Zen2 ymm registers rolling back

From: Tavis Ormandy
Date: Tue Mar 07 2023 - 11:49:31 EST


On Wed, Mar 01, 2023 at 09:54:14AM +0100, Borislav Petkov wrote:
> On Wed, Mar 01, 2023 at 12:23:01AM +0000, Andrew Cooper wrote:
> > So we need a table for all Zen2 parts of ucode revisions below which we
> > force hide XSAVES as the erratum workaround.
>
> Working on it - stay tuned.
>

FYI, I heard from someone offlist that they can reproduce with the
latest microcode available on this cpu:

cpu family : 23
model : 17
model name : AMD Ryzen 3 2200G with Radeon Vega Graphics
stepping : 0
microcode : 0x8101016

It seems likely many zen1 systems are affected without any microcode
patch, which seems not great to me.

I guess it would be nice if AMD could provide a list of devices they're
not going to provide a patch for...

Tavis.

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