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Wong" , Jan Kara , Josef Bacik , LKML , Linux-MM , syzkaller-bugs , william.kucharski@oracle.com, Matthew Wilcox Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, May 11, 2020 at 7:31 PM Mike Christie wrote: > > On 5/11/20 8:19 AM, syzbot wrote: > > syzbot has bisected this bug to: > > > > commit 2da22da573481cc4837e246d0eee4d518b3f715e > > Author: Mike Christie > > Date: Tue Aug 13 16:39:52 2019 +0000 > > > > nbd: fix zero cmd timeout handling v2 > > > > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=11d6ab14100000 > > start commit: e99332e7 gcc-10: mark more functions __init to avoid secti.. > > git tree: upstream > > final crash: https://syzkaller.appspot.com/x/report.txt?x=13d6ab14100000 > > console output: https://syzkaller.appspot.com/x/log.txt?x=15d6ab14100000 > > kernel config: https://syzkaller.appspot.com/x/.config?x=8a96cf498e199d8b > > dashboard link: https://syzkaller.appspot.com/bug?extid=518c54e255b5031adde4 > > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=146e45ec100000 > > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=164444a4100000 > > > > Reported-by: syzbot+518c54e255b5031adde4@syzkaller.appspotmail.com > > Fixes: 2da22da57348 ("nbd: fix zero cmd timeout handling v2") > > > > For information about bisection process see: https://goo.gl/tpsmEJ#bisection > > > > How do you adjust/modify what is expected from the test or what is > reported as an error? > > The patch added back behavior that got removed. With the patch we expect > the hung task warnings, because we specifically want to hold onto > running commands for longer than 120/hung_task_timeout seconds Hi Mike, All task hung messages are considered a kernel bug. So far this was always true as far as I can tell. Tasks that are blocked for any prolonged period should be killable.