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Wed, 19 Oct 2022 02:53:35 +0000 Date: Wed, 19 Oct 2022 10:53:38 +0800 From: Pengfei Xu To: Miklos Szeredi CC: , Subject: Re: [Syzkaller] INFO: task hung in fuse_lookup with v6.0 kernel in guest Message-ID: References: Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: X-ClientProxiedBy: SG2PR01CA0159.apcprd01.prod.exchangelabs.com (2603:1096:4:28::15) To PH0PR11MB4839.namprd11.prod.outlook.com (2603:10b6:510:42::18) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: PH0PR11MB4839:EE_|BL3PR11MB6362:EE_ X-MS-Office365-Filtering-Correlation-Id: c8f1eee6-8a8f-41e2-889a-08dab17d1d7c X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:PH0PR11MB4839.namprd11.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230022)(346002)(136003)(366004)(396003)(39860400002)(376002)(451199015)(2906002)(26005)(186003)(478600001)(6512007)(6506007)(83380400001)(4001150100001)(107886003)(44832011)(5660300002)(53546011)(6916009)(8936002)(66476007)(6486002)(66946007)(8676002)(4326008)(41300700001)(66556008)(316002)(82960400001)(86362001)(38100700002);DIR:OUT;SFP:1102; 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In my tests this works, > so I'm not sure there's anything to fix here. Thanks for the solution: "echo 1 > /sys/fs/fuse/connections/$FUSE_DEV/abort" > > Is there a real life situation where this occurs, or is this just > triggered with fuzzing? It only could be reproduced by repro.c from syzkaller, and we have not encountered this problem in real life yet. So it's a low priority issue and it's not even clear if it's worth solving? > > I'm wondering why syzbot didn't try aborting using the "abort" file in > sysfs, AFAICS it does know this trick. Yes, maybe syzbot should improve it? :) Thanks! BR. > > Thanks, > Miklos >