From: "Rafael J. Wysocki" <rjw@rjwysocki.net>
To: Borislav Petkov <bp@alien8.de>
Cc: Toshi Kani <toshi.kani@hpe.com>, mchehab@kernel.org,
        tony.luck@intel.com, lenb@kernel.org, linux-acpi@vger.kernel.org,
        linux-edac@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3 3/5] ghes_edac: add platform check to enable ghes_edac
Date: Wed, 23 Aug 2017 22:46:42 +0200
Message-ID: <2234003.7P8fBnLXh9@aspire.rjw.lan>
In-Reply-To: <20170823162053.4nns6ytekw5fychw@pd.tnic>
References: <20170818194644.14538-1-toshi.kani@hpe.com> <20170818194644.14538-4-toshi.kani@hpe.com> <20170823162053.4nns6ytekw5fychw@pd.tnic>
MIME-Version: 1.0
Content-Transfer-Encoding: 7Bit
Content-Type: text/plain; charset="us-ascii"
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 2631
Lines: 64

On Wednesday, August 23, 2017 6:20:53 PM CEST Borislav Petkov wrote:
> On Fri, Aug 18, 2017 at 01:46:42PM -0600, Toshi Kani wrote:
> > The ghes_edac driver was introduced in 2013 [1], but it has not
> > been enabled by any distro yet.  This driver obtains error info
> > from firmware interfaces, which are not properly implemented on
> > many platforms, as the driver always emits the messages below:
> > 
> >  This EDAC driver relies on BIOS to enumerate memory and get error reports.
> >  Unfortunately, not all BIOSes reflect the memory layout correctly
> >  So, the end result of using this driver varies from vendor to vendor
> >  If you find incorrect reports, please contact your hardware vendor
> >  to correct its BIOS.
> > 
> > To get out from this situation, add a platform check to selectively
> > enable the driver on the platforms that are known to have proper
> > firmware implementation.  Platform vendors can add their platforms
> > to the list when they support ghes_edac.
> > 
> > "ghes_edac.force_load=1" skips this platform check.
> > 
> > [1]: https://lwn.net/Articles/538438/
> > Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
> > Cc: Borislav Petkov <bp@alien8.de>
> > Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
> > Cc: Tony Luck <tony.luck@intel.com>
> > ---
> >  drivers/edac/ghes_edac.c |   28 +++++++++++++++++++++++-----
> >  1 file changed, 23 insertions(+), 5 deletions(-)
> 
> Ok, for the remaining three, I've updated my "ghes" branch here:
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/bp/bp.git/log/?h=ghes
> 
> Please, redo them ontop.
> 
> @Rafael: how do you want to handle this?
> 
> The first two are ACPI patches and the remaining three are EDAC. It
> would be probably easier if you acked the ACPI ones (but wait until
> Toshi's next version) and took them all through the EDAC tree as I have
> two more reworking that ghes_edac driver.

So I have some pending intel_pstate and the intel_pstate changes are likely
to conflict with it.

> Alternatively, they could all go through the ACPI tree but you'll have
> to pick them all up together.

That can be done. :-)

> That shouldn't be a problem either as all
> changes are solely to drivers/edac/ghes_edac.c and there's one other
> patch in my EDAC pile which touches ghes_edac.c:
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/bp/bp.git/diff/drivers/edac/ghes_edac.c?h=for-next&id=c54182ec0e157988f0cafd1e8d37b68ab4210f87
> 
> That's why I say, it'll be easier if I carried them all. :)
> 
> But I'm sure we can work something out.

I can expose a branch with this series for you to merge if that helps.

Thanks,
Rafael