[syzbot] INFO: task can't die in mark_held_locks

From: syzbot
Date: Fri Sep 03 2021 - 04:17:35 EST


Hello,

syzbot found the following issue on:

HEAD commit: 5e63226c7228 Add linux-next specific files for 20210827
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=11a143a9300000
kernel config: https://syzkaller.appspot.com/x/.config?x=9c03a8fdabc6b3ae
dashboard link: https://syzkaller.appspot.com/bug?extid=fe9fdd59a80d52730e2a
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.1

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+fe9fdd59a80d52730e2a@xxxxxxxxxxxxxxxxxxxxxxxxx

INFO: task syz-executor.1:6384 can't die for more than 143 seconds.
task:syz-executor.1 state:R running task stack:27752 pid: 6384 ppid: 6576 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:4955 [inline]
__schedule+0x940/0x26f0 kernel/sched/core.c:6302
mark_held_locks+0x9f/0xe0 kernel/locking/lockdep.c:4194

Showing all locks held in the system:
1 lock held by khungtaskd/26:
#0: ffffffff8b97fbe0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446
1 lock held by in:imklog/6244:
#0: ffff888024b2dc70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990
3 locks held by kworker/1:5/8059:
#0: ffff8880b9d31a98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:474 [inline]
#0: ffff8880b9d31a98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1319 [inline]
#0: ffff8880b9d31a98 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1622 [inline]
#0: ffff8880b9d31a98 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x236/0x26f0 kernel/sched/core.c:6216
#1: ffff8880b9d1f9c8 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39d/0x480 kernel/sched/psi.c:880
#2: ffffffff902c2780 (&ssp->srcu_gp_mutex){+.+.}-{3:3}, at: srcu_advance_state kernel/rcu/srcutree.c:1177 [inline]
#2: ffffffff902c2780 (&ssp->srcu_gp_mutex){+.+.}-{3:3}, at: process_srcu+0x31/0xec0 kernel/rcu/srcutree.c:1325
3 locks held by systemd-udevd/10966:
#0: ffff8880b9d31a98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:474 [inline]
#0: ffff8880b9d31a98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1319 [inline]
#0: ffff8880b9d31a98 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1622 [inline]
#0: ffff8880b9d31a98 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x236/0x26f0 kernel/sched/core.c:6216
#1: ffff8880b9d1f9c8 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39d/0x480 kernel/sched/psi.c:880
#2: ffffffff8c142c18 (tomoyo_ss){....}-{0:0}, at: tomoyo_path2_perm+0x20a/0x6b0 security/tomoyo/file.c:952
1 lock held by systemd-udevd/10995:
1 lock held by systemd-udevd/11008:
#0: ffff88807ee30460 (sb_writers#3){.+.+}-{0:0}, at: open_last_lookups fs/namei.c:3339 [inline]
#0: ffff88807ee30460 (sb_writers#3){.+.+}-{0:0}, at: path_openat+0x25c9/0x2740 fs/namei.c:3556
4 locks held by kworker/u4:8/20266:
1 lock held by syz-executor.1/6384:

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