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Message-ID: <6af0488a5d845028978f57e63f3706f8899465cf.camel@kernel.org>
Subject: Re: [PATCH 1/1] cxl/acpi.c: Add buggy BIOS hint for CXL ACPI lookup
 failure
From: PJ Waskiewicz <ppwaskie@kernel.org>
To: Dan Williams <dan.j.williams@intel.com>, Bjorn Helgaas
 <helgaas@kernel.org>
Cc: linux-cxl@vger.kernel.org, linux-pci@vger.kernel.org, 
	linux-kernel@vger.kernel.org
Date: Thu, 02 May 2024 10:34:33 -0700
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On Wed, 2024-05-01 at 08:47 -0700, Dan Williams wrote:
> PJ Waskiewicz wrote:
> > Buggy BIOS, that above value resolves to CX02.=C2=A0 In fact, it
> > *should* be
> > 49.=C2=A0 This is very much a bug in the ACPI arena.
>=20
> Ok, so back to this patch in question, my concern with upgrading:
>=20
> =C2=A0=C2=A0=C2=A0 dev_err(dev, "unable to retrieve _UID\n");
>=20
> ...to say "potentially buggy BIOS", is that same charge could be
> levied
> against all of the dev_warn() and dev_err() instances in
> drivers/cxl/acpi.c. So, it's not clear to me that cxl_acpi driver
> failures need to be more explicit.
>=20
> Otherwise, pretty much any ACPI hiccup message in the kernel would be
> candidate for claiming "BIOS is busted".

I really do like your patch you proposed a few weeks back.  I'm happy
to pull that and test it if you'd like to move forward on that instead.

Personally, I think the amount of discussion generated around this
simple "the BIOS is broken" should warrant some level of change to help
others not in-the-know to understand why their shiny new CXL devices
fell over on init.  Whatever that change looks like though, I'm not
married to any particular approach.

-PJ