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Date: Mon, 22 Apr 2024 17:16:07 -0700
From: Dan Williams <dan.j.williams@intel.com>
To: Ira Weiny <ira.weiny@intel.com>, Dave Jiang <dave.jiang@intel.com>, "Dan
 Williams" <dan.j.williams@intel.com>, Jonathan Cameron
	<jonathan.cameron@huawei.com>, Smita Koralahalli
	<Smita.KoralahalliChannabasappa@amd.com>, Shiju Jose <shiju.jose@huawei.com>
CC: Dan Carpenter <dan.carpenter@linaro.org>, Yazen Ghannam
	<yazen.ghannam@amd.com>, Davidlohr Bueso <dave@stgolabs.net>, "Alison
 Schofield" <alison.schofield@intel.com>, Vishal Verma
	<vishal.l.verma@intel.com>, Ard Biesheuvel <ardb@kernel.org>,
	<linux-efi@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
	<linux-cxl@vger.kernel.org>, Ira Weiny <ira.weiny@intel.com>, "Rafael J.
 Wysocki" <rafael@kernel.org>, Tony Luck <tony.luck@intel.com>, "Borislav
 Petkov" <bp@alien8.de>
Subject: RE: [PATCH v2 3/3] ras/events: Trace CXL CPER events without CXL
 stack
Message-ID: <6626fdc7b7e31_690a294a6@dwillia2-xfh.jf.intel.com.notmuch>
References: <20240422-cxl-cper3-v2-0-5cdd378fcd0b@intel.com>
 <20240422-cxl-cper3-v2-3-5cdd378fcd0b@intel.com>
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Ira Weiny wrote:
> If CXL is solely managed by firmware (including HDM configuration and
> event processing via firmware first) it is possible to run the system
> without the CXL software loaded.  In this case no CXL callback will be
> loaded and CXL CPER errors will not be processed at all.
> 
> In this case memory device and region (HPA) information is missing but
> omitting the error completely is not friendly.  Some device information
> is available the event.
> 
> Trace CXL CPER events if the CXL stack is not loaded.  A balance was
> chosen to decode only the CPER header as this configuration is likely
> rare.

I think the justification for this is weak and it pollutes the user ABI.
What environment cares about CXL RAS without the CXL driver? If such a
use case ever pops up it is trivial to revive this otherwise saves
carrying this and all the minor maintenance overhead it causes.