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Wysocki" , Jonathan Corbet , linux-cxl@vger.kernel.org, Tony Luck , Borislav Petkov , Hanjun Guo , Mauro Carvalho Chehab , Shuai Xue , Len Brown , Ira Weiny , Li Ming , Shuah Khan , Ben Cheatham , Richard Cheng , Robert Richter , Lukas Wunner , linux-pci@vger.kernel.org, linux-acpi@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org References: <20260902133933.2992457-1-terry.bowman@amd.com> <20260902133933.2992457-2-terry.bowman@amd.com> <20260908015144.62ee9c1c@jic23-huawei> <20260909230231.3fe72037@jic23-hlaptop> Content-Language: en-US From: "Bowman, Terry" In-Reply-To: <20260909230231.3fe72037@jic23-hlaptop> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-ClientProxiedBy: DM6PR02CA0113.namprd02.prod.outlook.com (2603:10b6:5:1b4::15) To CH8PR12MB9766.namprd12.prod.outlook.com (2603:10b6:610:2b6::10) Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CH8PR12MB9766:EE_|SA3PR12MB324744:EE_ X-MS-Office365-Filtering-Correlation-Id: 7b450187-a54a-485c-09de-08df0f4bda85 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|7416014|1800799024|23010399003|366016|10067099003|4143699003|11063799006|56012099006|22082099003|18002099003; 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Was there a reply to an earlier version with a >>> discussion of that? I'm not against the change but a 'why' >>> here would be good to have. >>> >> >> The driver panics on kfifo full error during UCE enqueue. This was recommended by you and >> Richard. Changes are at the link below in cxl_forward_error(): >> https://lore.kernel.org/linux-cxl/20260902133933.2992457-2-terry.bowman@amd.com/ >> > Panic on UCE is a given and correct. I ran the not panic on correctable via some > of our folk and they were fine with it (at least so far!). I just saw that > you'd stopped panic on this as part of the change log and wondered why. > > Not a problem, just following the breadcrumbs! > > Jonathan Hi Jonathan, This area was raised during your and Richard's v18 reviews. The comments: https://lkml.org/lkml/2026/7/23/446 v19 already implemented the fix from that review: panic on UCE, drop (log) on CE. The v18 code had dropped every severity on overflow without panicking, and you and Richard pointed out a dropped UCE must not be silently lost. v20 only tidied the CE branch (early return + clearer log message). The panic policy itself is unchanged since v19. -Terry