From: Palash Oswal <oswalpalash@gmail.com>
To: Hillf Danton <hdanton@sina.com>, axboe@kernel.dk
Cc: io-uring@vger.kernel.org, linux-kernel@vger.kernel.org,
syzkaller-bugs@googlegroups.com,
Pavel Begunkov <asml.silence@gmail.com>,
viro@zeniv.linux.org.uk, will@kernel.org, rostedt@goodmis.org,
peterz@infradead.org, mingo@redhat.com, mingo@kernel.org,
linux-fsdevel@vger.kernel.org
Subject: Re: INFO: task hung in __io_uring_task_cancel
Date: Mon, 4 Jan 2021 10:53:20 +0530 [thread overview]
Message-ID: <CAGyP=7eJKvVXDK+qo9d-AmxC2=QCKPKeGrEJm1bcYNN9f4AKmg@mail.gmail.com> (raw)
In-Reply-To: <20210103123701.1500-1-hdanton@sina.com>
Hillf -
> Can you reproduce it again against 5.11-rc1 with the tiny diff applied
> to see if there is a missing wakeup in the mainline?
Hey Hillf, thanks for sharing the diff. It seems like the reproducer
that I had sent did not work on 5.11-rc1 itself, so I'm trying to get
an updated reproducer for that.
I'm not well versed with the io_uring code yet, and therefore it'll
take me longer to get the reproducer going for 5.11-rc1.
Jens -
> Can you see if this helps? The reproducer is pretty brutal, it'll fork
> thousands of tasks with rings! But should work of course. I think this
> one is pretty straight forward, and actually an older issue with the
> poll rewaiting.
Hey Jens, I applied your diff to 5.10.4 (
b1313fe517ca3703119dcc99ef3bbf75ab42bcfb ), and unfortunately, I'm
still seeing the task being hung. Here's the console log if this helps
further -
root@syzkaller:~# [ 242.840696] INFO: task repro:395 blocked for more
than 120 seconds.
[ 242.846353] Not tainted 5.10.4+ #9
[ 242.849951] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs"
disables this message.
[ 242.857665] task:repro state:D stack: 0 pid: 395
ppid: 394 flags:0x00000004
[ 242.867346] Call Trace:
[ 242.870521] __schedule+0x28d/0x7e0
[ 242.873597] ? __percpu_counter_sum+0x75/0x90
[ 242.876794] schedule+0x4f/0xc0
[ 242.878803] __io_uring_task_cancel+0xad/0xf0
[ 242.880952] ? wait_woken+0x80/0x80
[ 242.882330] bprm_execve+0x67/0x8a0
[ 242.884142] do_execveat_common+0x1d2/0x220
[ 242.885610] __x64_sys_execveat+0x5d/0x70
[ 242.886708] do_syscall_64+0x38/0x90
[ 242.887727] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 242.889298] RIP: 0033:0x7ffabedd6469
[ 242.890265] RSP: 002b:00007ffc56b8bc78 EFLAGS: 00000246 ORIG_RAX:
0000000000000142
[ 242.892055] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ffabedd6469
[ 242.893776] RDX: 0000000000000000 RSI: 0000000020000180 RDI: 00000000ffffffff
[ 242.895400] RBP: 00007ffc56b8bc90 R08: 0000000000000000 R09: 00007ffc56b8bc90
[ 242.896879] R10: 0000000000000000 R11: 0000000000000246 R12: 0000559c19400bf0
[ 242.898335] R13: 00007ffc56b8bdb0 R14: 0000000000000000 R15: 0000000000000000
[ 363.691144] INFO: task repro:395 blocked for more than 241 seconds.
[ 363.693724] Not tainted 5.10.4+ #9
[ 363.695513] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs"
disables this message.
[ 363.700543] task:repro state:D stack: 0 pid: 395
ppid: 394 flags:0x00000004
[ 363.705747] Call Trace:
[ 363.707359] __schedule+0x28d/0x7e0
[ 363.709603] ? __percpu_counter_sum+0x75/0x90
[ 363.712900] schedule+0x4f/0xc0
[ 363.715002] __io_uring_task_cancel+0xad/0xf0
[ 363.718026] ? wait_woken+0x80/0x80
[ 363.720137] bprm_execve+0x67/0x8a0
[ 363.721992] do_execveat_common+0x1d2/0x220
[ 363.723997] __x64_sys_execveat+0x5d/0x70
[ 363.725857] do_syscall_64+0x38/0x90
[ 363.727501] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 363.729510] RIP: 0033:0x7ffabedd6469
[ 363.730913] RSP: 002b:00007ffc56b8bc78 EFLAGS: 00000246 ORIG_RAX:
0000000000000142
[ 363.733747] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ffabedd6469
[ 363.736138] RDX: 0000000000000000 RSI: 0000000020000180 RDI: 00000000ffffffff
[ 363.738431] RBP: 00007ffc56b8bc90 R08: 0000000000000000 R09: 00007ffc56b8bc90
[ 363.740504] R10: 0000000000000000 R11: 0000000000000246 R12: 0000559c19400bf0
[ 363.742560] R13: 00007ffc56b8bdb0 R14: 0000000000000000 R15: 0000000000000000
next prev parent reply other threads:[~2021-01-04 5:24 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-03 4:14 INFO: task hung in __io_uring_task_cancel Palash Oswal
2021-01-03 21:53 ` Jens Axboe
[not found] ` <20210103123701.1500-1-hdanton@sina.com>
2021-01-04 5:23 ` Palash Oswal [this message]
[not found] ` <20210104065231.2579-1-hdanton@sina.com>
2021-01-04 9:40 ` Palash Oswal
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