Re: [PATCH v2 1/5] x86/mce: Collect error message for severities below MCE_PANIC_SEVERITY

[Shuai Xue <xueshuai@linux.alibaba.com>]

在 2025/2/18 15:58, Borislav Petkov 写道:
> On Mon, Feb 17, 2025 at 02:33:31PM +0800, Shuai Xue wrote:
>> Currently, mce_no_way_out() only collects error messages when the error
>> severity is equal to `MCE_PANIC_SEVERITY`. To improve diagnostics,
>> modify the behavior to also collect error messages when the severity is
>> less than `MCE_PANIC_SEVERITY`.
> 
> That function is literally called "no way out" as in, is the error severe
> enough so that there is no way out.
> 
> Now you went and stomped all over that to "improve diagnostics". What
> diagnostsics? Your commit messages need to explain in detail why exactly
> a patch exists.
> 
> So nope.
> 

Hi, Borislav,

Thank you for reply.

The msg in predefined `severities`, e.g.

	MCESEV(
		AO, "Action optional: last level cache writeback error",
		SER, MASK(MCI_UC_AR|MCACOD, MCI_STATUS_UC|MCACOD_L3WB)
		),

is helpful for users to know what kind of MCE is happened. For a fatal machine
check, kernel panic use the message and I want to extend to collect the message
and print it out for non-fatal one.

If you don't object, let's go on to discuss how to implement it.
Otherwise, you can ignore the following response.

Yes, mce_no_way_out() means "no way out" literally. It only collects message
for MCE_PANIC_SEVERITY but use in common path. So I used this function to
extend it to non-fatal, assuming it was obvious.
  
Is __mc_scan_banks() a proper function to extend?

Thanks.
Shuai