Hi Thomas,
> On Aug 30, 2019, at 03:45, Thomas Gleixner <t...@linutronix.de> wrote:
>
> On Thu, 29 Aug 2019, Kai-Heng Feng wrote:
>> at 20:13, Thomas Gleixner <t...@linutronix.de> wrote:
>>> On Thu, 29 Aug 2019, Kai-Heng Feng wrote:
>>>
>>>> Some Coffee Lake platforms have skewed HPET timer once the SoCs entered
>>>> PC10, and marked TSC as unstable clocksource as result.
>>>
>>> So here you talk about Coffee Lake and in the patch you use KABYLAKE.
>>
>> Coffeelake has the same model number as Kabylake.
>
> Yeah, just a bit more text explaining that would be helpful.
>
>>>> +static const struct x86_cpu_id hpet_blacklist[] __initconst = {
>>>> + { X86_VENDOR_INTEL, 6, INTEL_FAM6_KABYLAKE_MOBILE },
>>>> + { X86_VENDOR_INTEL, 6, INTEL_FAM6_KABYLAKE_DESKTOP },
>>>
>>> So this disables HPET on all Kaby Lake variants not just on the affected
>>> Coffee Lakes. I know that I rejected the initial patch with the random
>>> stepping cutoff...
>>>
>>> https://lore.kernel.org/lkml/alpine.deb.2.21.1904081403220.1...@nanos.tec.linutronix.de
>>>
>>> In the other attempt to 'fix' this I asked for clarification, but silence
>>> from Intel after this:
>>>
>>> https://lore.kernel.org/lkml/alpine.deb.2.21.1905182015320.3...@nanos.tec.linutronix.de
>>>
>>> Can Intel please provide some useful information about this finally?
>>
>> Hopefully Intel can provide more info.
>>
>> I know we should find the root cause rather than stopping at "it’s a firmware
>> bug”, but users are already affected by this issue [1].
>> Is there any better short-term workaround?
>
> Not really. And if Intel stays silent, I'm just going to apply it as is
> along with a stable tag.
Seems like there's still no updates from Intel. Can we have this patch in v5.4?
Kai-Heng
>
> Thanks,
>
> tglx
