From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 716BAC433FE for ; Mon, 21 Nov 2022 11:56:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229662AbiKUL41 (ORCPT ); Mon, 21 Nov 2022 06:56:27 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56026 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229498AbiKUL40 (ORCPT ); Mon, 21 Nov 2022 06:56:26 -0500 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A6BA563174; Mon, 21 Nov 2022 03:56:25 -0800 (PST) Received: from fraeml712-chm.china.huawei.com (unknown [172.18.147.200]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4NG5MN3YMSz68B2l; Mon, 21 Nov 2022 19:51:28 +0800 (CST) Received: from lhrpeml500005.china.huawei.com (7.191.163.240) by fraeml712-chm.china.huawei.com (10.206.15.61) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Mon, 21 Nov 2022 12:56:23 +0100 Received: from localhost (10.202.227.76) by lhrpeml500005.china.huawei.com (7.191.163.240) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Mon, 21 Nov 2022 11:56:22 +0000 Date: Mon, 21 Nov 2022 11:56:21 +0000 From: Jonathan Cameron To: Dave Jiang CC: , , , , , , , , Subject: Re: [PATCH v3 09/11] cxl/pci: Add (hopeful) error handling support Message-ID: <20221121115621.00002b92@Huawei.com> In-Reply-To: <166879133596.674819.10879693357035405104.stgit@djiang5-desk3.ch.intel.com> References: <166879123216.674819.3578187187954311721.stgit@djiang5-desk3.ch.intel.com> <166879133596.674819.10879693357035405104.stgit@djiang5-desk3.ch.intel.com> Organization: Huawei Technologies Research and Development (UK) Ltd. X-Mailer: Claws Mail 4.1.0 (GTK 3.24.33; x86_64-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.202.227.76] X-ClientProxiedBy: lhrpeml100006.china.huawei.com (7.191.160.224) To lhrpeml500005.china.huawei.com (7.191.163.240) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Fri, 18 Nov 2022 10:08:55 -0700 Dave Jiang wrote: > From: Dan Williams > > Add nominal error handling that tears down CXL.mem in response to error > notifications that imply a device reset. Given some CXL.mem may be > operating as System RAM, there is a high likelihood that these error > events are fatal. However, if the system survives the notification the > expectation is that the driver behavior is equivalent to a hot-unplug > and re-plug of an endpoint. > > Note that this does not change the mask values from the default. That > awaits CXL _OSC support to determine whether platform firmware is in > control of the mask registers. > > Signed-off-by: Dan Williams > Signed-off-by: Dave Jiang Maybe something for the future, but if multiple errors are reported in the CXL RAS structures, we should be able to keep iterating to report them all + reset just the once. I think that relies on Multiple_Header_Recording_Capability though if we want useful data. Looks good to me though I have messaged one of our RAS experts to take a look as I only end up touching this aspect of PCI drivers once in a blue moon! Reviewed-by: Jonathan Cameron