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Date: Wed, 5 Jun 2024 20:02:52 +0800
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Subject: Re: [PATCH] x86/hpet: Read HPET directly if panic in progress
To: Borislav Petkov <bp@alien8.de>
CC: Thomas Gleixner <tglx@linutronix.de>, Linus Torvalds
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From: Tony W Wang-oc <TonyWWang-oc@zhaoxin.com>
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On 2024/6/5 19:33, Borislav Petkov wrote:
> 
> 
> [这封邮件来自外部发件人 谨防风险]
> 
> On Wed, Jun 05, 2024 at 06:10:07PM +0800, Tony W Wang-oc wrote:
>> It may also happen without setting fake_panic, such as an MCE error of the
>> UCNA/SRAO type occurred?
> 
> 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.

Sincerely
TonyWWang-oc
> --
> Regards/Gruss,
>      Boris.
> 
> https://people.kernel.org/tglx/notes-about-netiquette