Re: [PATCH v1.1 2/2] x86/hpet: Don't enable legacy replacement mode unconditionally

[Jan Beulich <jbeulich@xxxxxxxx>]

On 26.03.2021 13:29, Ian Jackson wrote:
> I wrote:
>> I'm sorry, but I think it is too late for 4.15 to do this.  I prefer
>> Jan's patch which I have alread release-acked.
>>
>> Can someone qualified please provide a maintainer review for this,
>> ideally today ?
> 
> I asked Andrew on IRC:
> 
> 12:08 <Diziet> andyhhp__: Are you prepared to maintainer-ack Jan's
>                more-minimal hpet workaround approach ?
> 12:16 <andyhhp__> Diziet: honestly, no.  I don't consider that
>                   acceptable behaviour, and it is a fairly big "f you"
>                   (this was literally feedback I got in private) to
>                   the downstreams who've spent years trying to get us
>                   to fix this bug, and have now backported the first
>                   version.
> 12:16 <andyhhp__> I'm looking into the feedback on my series
> 12:17 <andyhhp__> one way or another, the moment we enter the fallback
>                   path for interrupt routing, something is very broken
>                   on the system
> 12:19 <andyhhp__> so the tradeoff is an unspecified bug on one ancient
>                   laptop which can't be tested now, vs 5 years of Atom
>                   CPUs, 2 years of latop CPUs, and the forthcoming
>                   Server line of Intel CPUs
> 12:19 <andyhhp__> or whatever other compromise we can work on
> 
> I'm sorry that this bug is going to continue to be not properly fixed.

Actually I had another thought here in the morning, but then didn't
write it down: While Andrew's approach indeed would (hopefully)
improve user experience, it'll reduce the incentive of actually
fixing the issue. Normally I might not be that concerned, but seeing
how long it took to even arrive at a workaround, I'm afraid now I am
concerned.

Jan