Re: [PATCH 0/2] x86/rdrand: implement sanity check for RDSEED

From: Borislav Petkov
Date: Wed Mar 12 2025 - 08:46:58 EST


On Wed, Mar 12, 2025 at 03:31:28PM +0300, Mikhail Paulyshka wrote:
> On the AMD Cyan Skillfish (Family 0x17 Model 0x47 Stepping 0x0), which
> is a Zen2-based APU found on the AMD BC-250 board, there is a situation
> where RDRAND works fine, but RDSEED generates FF. This leads to some
> applications that use RDSEED to generate random numbers (such as
> Qt and KDE) into a nearly unusable state.
>
> Although AMD has fixed the Zen2 RDRAND issues in 2019 with a microcode update,
> no such update has been released for the Family 0x17 Model 0x47 core.

What's the microcode level on that machine?

Also, send

cpuid -r

output pls.

Thx.

--
Regards/Gruss,
Boris.

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