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Message-ID: Date: Fri, 19 May 2023 10:33:26 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.10.1 Subject: Re: [PATCH v1] xen/sched/null: avoid crash after failed domU creation Content-Language: en-US To: Stewart Hildebrand Cc: George Dunlap , Dario Faggioli , Juergen Gross , xen-devel@lists.xenproject.org References: <20230501203046.168856-1-stewart.hildebrand@amd.com> <30246788-c90e-e338-de4b-e7bb2e440f4e@suse.com> <93adef92-90fb-80de-c6b4-b41872b74682@amd.com> From: Jan Beulich In-Reply-To: <93adef92-90fb-80de-c6b4-b41872b74682@amd.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-ClientProxiedBy: FR3P281CA0066.DEUP281.PROD.OUTLOOK.COM (2603:10a6:d10:4b::17) To VE1PR04MB6560.eurprd04.prod.outlook.com (2603:10a6:803:122::25) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: VE1PR04MB6560:EE_|DBBPR04MB7835:EE_ X-MS-Office365-Filtering-Correlation-Id: 4bd282a2-61c5-4efc-a526-08db5843b6ae X-LD-Processed: f7a17af6-1c5c-4a36-aa8b-f5be247aa4ba,ExtFwd X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; 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Since the unit was >>>    offline, unit_assign() was not called, and null_unit_insert() returned. >>> * Later during domain creation, the unit was onlined >>> * Eventually, domain creation failed due to bad configuration >>> * null_unit_remove() was invoked with the unit still online. Since the unit was >>>    online, it called unit_deassign() and triggered an ASSERT. >>> >>> To fix this, only call unit_deassign() when npc->unit is non-NULL in >>> null_unit_remove. >>> >>> Signed-off-by: Stewart Hildebrand >> >> Reviewed-by: Juergen Gross > > Thanks for the review. Does this still need a maintainer ack? In principle yes. I might be willing to time out at some point, but not before at least one ping was sent (and some more time has passed afterwards). Jan