linux-kernel - Re: [PATCH 6/9] x86/mce: Unify AMD THR handler with MCA Polling

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Message-ID: <20240816140106.GA29375@yaz-khff2.amd.com>
Date: Fri, 16 Aug 2024 10:01:06 -0400
From: Yazen Ghannam <yazen.ghannam@....com>
To: Borislav Petkov <bp@...en8.de>
Cc: linux-edac@...r.kernel.org, linux-kernel@...r.kernel.org,
	tony.luck@...el.com, x86@...nel.org, avadhut.naik@....com,
	john.allen@....com
Subject: Re: [PATCH 6/9] x86/mce: Unify AMD THR handler with MCA Polling

On Mon, Jun 03, 2024 at 08:04:09PM +0200, Borislav Petkov wrote:
> On Thu, May 23, 2024 at 10:56:38AM -0500, Yazen Ghannam wrote:
> > diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
> > index 58b8efdcec0b..d6517b93c903 100644
> > --- a/arch/x86/kernel/cpu/mce/core.c
> > +++ b/arch/x86/kernel/cpu/mce/core.c
> > @@ -660,6 +660,12 @@ static noinstr void mce_read_aux(struct mce *m, int i)
> >  	}
> >  }
> >  
> > +static void reset_thr_limit(unsigned int bank)
> > +{
> > +	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
> > +		return amd_reset_thr_limit(bank);
> > +}
> > +
> >  DEFINE_PER_CPU(unsigned, mce_poll_count);
> >  
> >  static bool ser_log_poll_error(struct mce *m)
> > @@ -769,6 +775,8 @@ void machine_check_poll(enum mcp_flags flags, mce_banks_t *b)
> >  			mce_log(&m);
> >  
> >  clear_it:
> > +		reset_thr_limit(i);
> 
> 	if (mca_cfg.thresholding)
> 		reset_thr_limit(i);
> 
> and then you don't have to do a vendor check but simply set
> mca_cfg.thresholding on AMD after having defined it in the patch.
>

I can do that. The reset procedure is vendor-specific though. But we
only have the AMD case right now anyway.

There's already "mce_flags.amd_threshold" which got removed in patch 5
of this set. But I can keep that and reuse it here.

Thanks,
Yazen