Re: [PATCH] EDAC/mce_amd: Add missing long names for SMCA bank types

[Guixiong Wei]

> From: "Yazen Ghannam"<yazen.ghannam@xxxxxxx>
> Date:  Mon, Oct 19, 2026, 06:35
> Subject:  Re: [PATCH] EDAC/mce_amd: Add missing long names for SMCA bank types
> To: "Borislav Petkov"<bp@xxxxxxxxx>
> Cc: "Guixiong Wei"<weiguixiong@xxxxxxxxxxxxx>, "Tony Luck"<tony.luck@xxxxxxxxx>, "Muralidhara M K"<muralidhara.mk@xxxxxxx>, <linux-edac@xxxxxxxxxxxxxxx>, <linux-kernel@xxxxxxxxxxxxxxx>, <stable@xxxxxxxxxxxxxxx>
> On Sat, Oct 17, 2026 at 12:51:45PM -0700, Borislav Petkov wrote:
> > On Mon, Oct 12, 2026 at 10:03:30AM -0400, Yazen Ghannam wrote:
> > > These were intentionaly left out as it as it seems users have been
> > > moving to user space decode tools.
> > 
> > You're making the old mistake:
> > 
> > a. a naked MCE record in dmesg, you have to open the PPRs and actually decode
> > it by hand. Or use a tool but most of the time, that tool is not updated with
> > the latest error definitions, and you need the exact machine info in order for
> > the tool to decode properly, yadda yadda...
> > 
> > b. Get a fully decoded error string in dmesg.
> > 
> > What is better: a) or b) ?
> > 
> 
> "a" is better.
> 
> The same "is not updated with the latest error definitions" applies to
> the kernel.
> 
> And it's usually easier to update tools than patch the kernel (and also
> deal with backporting, etc.).
> 
> In any case, this patch isn't about error descriptions. It's only about
> adding the names for some bank types.
> 
> The bank types were added three years ago. AFAIK, the missing names
> haven't been an issue. So I'm curious if this patch is actually fixing a
> problem. If so, then that's fine.

I found this while reviewing decode_smca_error(), rather than from
an observed MCE or a user report. In particular, I was looking at:

        pr_emerg(HW_ERR "%s Ext. Error Code: %d",
                 smca_get_long_name(bank_type), xec);

For SMCA_MA_LLC, SMCA_USR_DP and SMCA_USR_CP, the corresponding
smca_long_names[] entries are unset, so smca_get_long_name() returns
NULL. The %s conversion would therefore print "(null)" instead of
the bank name.

That was what prompted the patch. I had assumed those entries were
an oversight; the intention was to make the existing log output
show the bank names.

Regarding Boris's earlier comment, I agree that the Cc: stable tag
was not justified here and will drop it.

Thanks for the feedback.

Guixiong
> 
> Thanks,
> Yazen
>