Re: Kernel 6.9 regression: X86: Bogus messages from topology detection

[Thomas Gleixner]

On Sat, Jun 01 2024 at 09:06, Linux regression tracking (Thorsten Leemhuis) wrote:
> On 31.05.24 10:42, Thomas Gleixner wrote:
>> On Fri, May 31 2024 at 10:33, Thomas Gleixner wrote:
>
>> ---
>> Subject: x86/topology/intel: Unlock CPUID before evaluating anything
>> From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
>> Date: Thu, 30 May 2024 17:29:18 +0200
>> 
>> Intel CPUs have a MSR bit to limit CPUID enumeration to leaf two. If this
>> bit is set by the BIOS then CPUID evaluation including topology enumeration
>> does not work correctly as the evaluation code does not try to analyze any
>> leaf greater than two.
>> [...]
>
> TWIMC, I noticed a bug report with a "12 × 12th Gen Intel® Core™
> i7-1255U" where the reporter also noticed a lot of messages like these:
>
> archlinux kernel: [Firmware Bug]: CPU4: Topology domain 1 shift 7 != 6
> archlinux kernel: [Firmware Bug]: CPU4: Topology domain 2 shift 7 != 6
> archlinux kernel: [Firmware Bug]: CPU4: Topology domain 3 shift 7 != 6
>
> Asked the reporter to test this patch. For details see:
> https://bugzilla.kernel.org/show_bug.cgi?id=218879

Won't help. See: https://lore.kernel.org/all/87plt26m2b.ffs@tglx/

Thanks,

        tglx