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

[Linux regression tracking (Thorsten Leemhuis)]

On 01.06.24 09:20, Thomas Gleixner wrote:
> 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/

Ahh, it was the other problem in this thread. Sorry for not noticing
that, had not followed things that closely. Forwarded that info to the
ticket. Many thx! Ciao, Thorsten