RE: [PATCH v3 0/8] AMD64 EDAC fixes

[Ghannam, Yazen]

> -----Original Message-----
> From: linux-edac-owner@xxxxxxxxxxxxxxx <linux-edac-owner@xxxxxxxxxxxxxxx> On Behalf Of Borislav Petkov
> Sent: Monday, August 26, 2019 9:59 AM
> To: Ghannam, Yazen <Yazen.Ghannam@xxxxxxx>
> Cc: Adam Borowski <kilobyte@xxxxxxxxxx>; linux-edac@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v3 0/8] AMD64 EDAC fixes
> 
> On Mon, Aug 26, 2019 at 02:19:18PM +0000, Ghannam, Yazen wrote:
> > I was tracking down the failure with ECC disabled, and that seems to be it.
> >
> > So I think we should return 0 "if (!edac_has_mcs())", because we'd only get
> > there if ECC is disabled on all nodes and there wasn't some other initialization
> > error.
> >
> > I'll send a patch for this soon.
> >
> > Adam, would you mind testing this patch?
> 
> You can't return 0 when ECC is disabled on all nodes because then the
> driver remains loaded without driving anything. That silly userspace
> needs to understand that ENODEV means "stop trying to load this driver".
> 

Yes, you're right.

I'll try and track down the interaction here between userspace and the module.
Please let me know if you have any suggestions.

Thanks,
Yazen