Re: [PATCH] x86/hpet: Read HPET directly if panic in progress

[Tony W Wang-oc]

On 2024/6/5 23:51, Luck, Tony wrote:
> [这封邮件来自外部发件人 谨防风险]
>
> > > Which types exactly do you mean when you're looking at the severities[]
> > > array in severity.c?
> > >
> > > And what scenario are you talking about?
> > >
> > > To get an #MC exception and detect only UCNA/SRAO errors? Can that even
> > > happen on any hardware?
> >
> > Yes, I mean an #MC exception happened and detect only like SRAO errors
> > like below:
> >
> >           MCESEV(
> >                   AO, "Action optional: memory scrubbing error",
> >                   SER, MASK(MCI_UC_AR|MCACOD_SCRUBMSK,
> > MCI_STATUS_UC|MCACOD_SCRUB)
> >                   ),
> >           MCESEV(
> >                   AO, "Action optional: last level cache writeback error",
> >                   SER, MASK(MCI_UC_AR|MCACOD, MCI_STATUS_UC|MCACOD_L3WB)
> >                   ),
> >
> > I think these errors are actually encountered on some platforms that
> > support these type of errors report to the #MC.
>
> Intel servers from Nehalem through Cascade Lake reported memory controller
> patrol scrub uncorrected error with #MC and SRAO signature.
>
> Icelake and newer use CMCI with a UCNA signature.

I have a question, does Intel use #MC to report UCNA errors?

Sincerely
TonyWWang-oc