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client-ip=165.204.84.17; helo=satlexmb07.amd.com; pr=C Received: from satlexmb07.amd.com (165.204.84.17) by SJ5PEPF00000204.mail.protection.outlook.com (10.167.244.37) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.382.8 via Frontend Transport; Tue, 1 Sep 2026 19:19:12 +0000 Received: from [10.236.189.59] (10.180.168.240) by satlexmb07.amd.com (10.181.42.216) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.46; Tue, 1 Sep 2026 14:19:12 -0500 Message-ID: <0ef743e4-2cc9-4823-b6de-e2babb1e1353@amd.com> Date: Tue, 1 Sep 2026 14:19:12 -0500 Precedence: bulk X-Mailing-List: linux-cxl@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird From: "Cheatham, Benjamin" Subject: Re: [PATCH v2 3/4] cxl/events: Bound the per-log Get Event Records loop To: Anisa Su , References: <20260901002912.958-1-anisa.su@samsung.com> <20260901002912.958-4-anisa.su@samsung.com> Content-Language: en-US In-Reply-To: <20260901002912.958-4-anisa.su@samsung.com> Content-Type: text/plain; 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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: yQ7AdNoSWH5cQcr/sTAOoyS+UdI530j+P6l6EQUBuyoGskjS1ShQQqbsH9lwG4LW5cMqJx1w0N8juS6GdVILLmsfor8SnymIpaaTnLszAiLTjQKcArnee1UTvCbDsmdXMQgRaW9YRur3UdkyuNqRIIzC8ihYwx6IHBWUZxxfIOlEPM+YfNKf0ueB0psp1NhaGe0xRGbUBP8D5MFqay+HpNbuOBXYjmfX8ZniL0lQND9yx9OlLZLQmLwvjOmtuXdSGBjVxCiRzsTIdVgggg4ynF6+/MFbXQuhivZ77fK9/3KbqR5DteI6IXsR9+jwetA2IdXOQn0J416A+nbs6sHfvUgobEHVUqMolrr/9F0G8RzQk5g2cWp/ikPYis0X1S7uqw3bsGwRttl8Yt8lIQfh53tuU/AoNkwLR2yzNVNjEk+s1Jj4anq2rYopSA1CW/Rp X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 01 Sep 2026 19:19:12.9668 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: b02c2024-44e2-4381-1446-08df085de839 X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: SJ5PEPF00000204.namprd05.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA5PPFE3F7EF2AE On 8/31/2026 7:26 PM, Anisa Su wrote: > cxl_mem_get_records_log() re-queries a log until the device reports it > empty. A misbehaving device that never stops reporting records keeps the > event thread stuck in this loop, and there is no cond_resched() to let anything > else on the CPU run. > > Cap the passes at 128 and reschedule between them. Each pass gets up to > a full mailbox payload of records from the log, so the cap is a generous > upper bound. Report hitting the cap as an error and let the caller give > up on the log. > > Fixes: 6ebe28f9ec72 ("cxl/mem: Read, trace, and clear events on driver load") > Signed-off-by: Anisa Su > --- Reviewed-by: Ben Cheatham