Re: [PATCH v2 1/1] x86/rdrand: disable RDSEED on AMD Cyan Skillfish

[Borislav Petkov]

On Mon, Jul 07, 2025 at 01:17:41PM +0300, Mikhail Paulyshka wrote:
> On 6/17/25 11:21 PM, Dave Hansen wrote:
> > Heh, maybe if x86_init_rdrand() did RDSEED too, this wouldn't have
> > slipped through QA.
> 
> This might be interesting to you: in V1 of this patch set, there was an
> RDSEED sanity check, and Intel's CI detected broken RDSEED on Comet Lake:
> 
> https://lore.kernel.org/all/202503211421.fc83271a-lkp@xxxxxxxxx/

Right, I'm being told this is preproduction hw:

[    2.823625][    T1] smpboot: CPU0: Genuine Intel(R) CPU 0000 @ 3.30GHz (family: 0x6, model: 0xa5, stepping: 0x1)

and strictly speaking, RDSEED *can* fail due to resources exhaustion etc
- doesn't necessarily mean it is broken.

Thx.

-- 
Regards/Gruss,
    Boris.

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