NACK/Cmt: [SRU][N:linux][PATCH 0/1] power: intel_pstate: Fix unchecked MSR

[Stefan Bader]

On 12/01/2026 16:56, Thibault Ferrante wrote:
> Introduce a regression which is fixed 4b747cc62 "cpufreq: intel_pstate: 
> Check IDA only before MSR_IA32_PERF_CTL writes"
> Fixing the back-port and including the new fix in the submission.

No, this does not work like that. You missed your chance to do that. 
This is applied already and the resulting kernel is prepared. You have 
to file a bug report ASAP to submit the fix and submit the missing patch 
urgently and request a re-spin from the cycle lead of 2025.01.12!!!

-Stefan
> 
> 
> On 19/12/2025 16:10, Thibault Ferrante wrote:
>> BugLink: https://bugs.launchpad.net/bugs/2130244
>>
>> [ Impact ]
>>
>>   * Access to trying to access /sys/devices/system/cpu/intel_pstate/ 
>> no_turbo on Skylake-X systems trigger an unchecked MSR access error: 
>> WRMSR to 0x199 (attempted to write 0x0000000100001300).
>>
>> [ Fix ]
>>
>>   * Clean cherry-pick from upstream:
>>    ac4e04d9e378 cpufreq: intel_pstate: Unchecked MSR aceess in legacy 
>> mode
>>
>> [ Test Plan ]
>>
>>   * Compiled.
>>
>> [ Where problems could occur ]
>>
>>   * Regression in turbo management in intel hardware.
>>
>> [ Other Info ]
>>
>>   * This is a public version of: https://bugs.launchpad.net/bugs/2115105
>>   * Already integrated in Plucky with https://bugs.launchpad.net/ 
>> bugs/2113881
>>
>> Srinivas Pandruvada (1):
>>    cpufreq: intel_pstate: Unchecked MSR aceess in legacy mode
>>
>>   drivers/cpufreq/intel_pstate.c | 3 +++
>>   1 file changed, 3 insertions(+)
>>
> 

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