syzbot


INFO: rcu detected stall in io_uring_release

Status: fixed on 2020/06/18 13:57
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+66243bb7126c410cefe6@syzkaller.appspotmail.com
Fix commit: 3fd44c86711f io_uring: use cond_resched() in io_ring_ctx_wait_and_kill()
First crash: 1665d, last: 1620d
Discussions (5)
Title Replies (including bot) Last reply
[PATCH 5.6 000/194] 5.6.14-rc1 review 203 (203) 2020/05/19 14:44
[PATCH AUTOSEL 5.6 01/50] RDMA/mlx4: Initialize ib_spec on the stack 50 (50) 2020/05/19 13:25
INFO: rcu detected stall in io_uring_release 1 (3) 2020/05/12 15:25
Re: INFO: rcu detected stall in io_uring_release 2 (2) 2020/04/20 12:57
Re: INFO: rcu detected stall in io_uring_release 1 (1) 2020/04/19 19:57

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (10524 ticks this GP) idle=0da/1/0x4000000000000002 softirq=8929/8931 fqs=5169 
	(t=10500 jiffies g=8737 q=703)
NMI backtrace for cpu 0
CPU: 0 PID: 8641 Comm: syz-executor.4 Not tainted 5.7.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1e9/0x30e lib/dump_stack.c:118
 nmi_cpu_backtrace+0x9f/0x180 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x16a/0x280 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x199/0x2a0 kernel/rcu/tree_stall.h:254
 print_cpu_stall kernel/rcu/tree_stall.h:475 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:549 [inline]
 rcu_pending kernel/rcu/tree.c:3225 [inline]
 rcu_sched_clock_irq+0x186a/0x1ac0 kernel/rcu/tree.c:2296
 update_process_times+0x12c/0x180 kernel/time/timer.c:1727
 tick_sched_handle kernel/time/tick-sched.c:176 [inline]
 tick_sched_timer+0x254/0x410 kernel/time/tick-sched.c:1320
 __run_hrtimer kernel/time/hrtimer.c:1520 [inline]
 __hrtimer_run_queues+0x42d/0x930 kernel/time/hrtimer.c:1584
 hrtimer_interrupt+0x373/0xd60 kernel/time/hrtimer.c:1646
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1113 [inline]
 smp_apic_timer_interrupt+0x109/0x280 arch/x86/kernel/apic/apic.c:1138
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:759 [inline]
RIP: 0010:lock_is_held_type+0x25b/0x2e0 kernel/locking/lockdep.c:4973
Code: 48 c1 e8 03 42 80 3c 38 00 74 0c 48 c7 c7 30 b9 2b 89 e8 68 8a 58 00 48 83 3d 80 e9 d2 07 00 0f 84 82 00 00 00 4c 89 f7 57 9d <0f> 1f 44 00 00 89 e8 48 83 c4 20 5b 41 5c 41 5d 41 5e 41 5f 5d c3
RSP: 0018:ffffc900063e79b0 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff1257726 RBX: 1ffff11013b62d90 RCX: ffff88809db163c0
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000000000286
RBP: 0000000000000000 R08: dffffc0000000000 R09: ffffed101100ce61
R10: ffffed101100ce61 R11: 0000000000000000 R12: ffff88809db16c84
R13: ffffffff892e8520 R14: 0000000000000286 R15: dffffc0000000000
 lock_is_held include/linux/lockdep.h:406 [inline]
 ___might_sleep+0x83/0x570 kernel/sched/core.c:6766
 io_ring_ctx_wait_and_kill+0xbe/0x820 fs/io_uring.c:7316
 io_uring_release+0x59/0x70 fs/io_uring.c:7338
 __fput+0x2ed/0x750 fs/file_table.c:280
 task_work_run+0x147/0x1d0 kernel/task_work.c:123
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x5ef/0x1f80 kernel/exit.c:796
 do_group_exit+0x15e/0x2c0 kernel/exit.c:894
 get_signal+0x13cf/0x1d60 kernel/signal.c:2739
 do_signal+0x33/0x610 arch/x86/kernel/signal.c:784
 exit_to_usermode_loop arch/x86/entry/common.c:161 [inline]
 prepare_exit_to_usermode+0x32a/0x600 arch/x86/entry/common.c:196
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45c829
Code: Bad RIP value.
RSP: 002b:00007f53ad17bc78 EFLAGS: 00000246 ORIG_RAX: 00000000000001a9
RAX: 0000000000000003 RBX: 00000000004e0ce0 RCX: 000000000045c829
RDX: 0000000000000000 RSI: 0000000020000580 RDI: 00000000000000f1
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000204 R14: 00000000004c425f R15: 00007f53ad17c6d4

Crashes (15):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/05/12 04:47 upstream 152036d1379f 9eb09c40 .config console log report syz ci-upstream-kasan-gce-smack-root
2020/05/12 02:17 linux-next ac935d227366 9eb09c40 .config console log report syz ci-upstream-linux-next-kasan-gce-root
2020/05/29 12:11 upstream 75caf310d16c d19ed305 .config console log report ci-upstream-kasan-gce-selinux-root
2020/05/29 12:07 upstream 75caf310d16c d19ed305 .config console log report ci-upstream-kasan-gce-smack-root
2020/05/29 12:02 upstream 75caf310d16c d19ed305 .config console log report ci-upstream-kasan-gce-root
2020/05/29 09:18 upstream 75caf310d16c d19ed305 .config console log report ci-upstream-kasan-gce-selinux-root
2020/05/29 09:15 upstream 75caf310d16c d19ed305 .config console log report ci-upstream-kasan-gce-smack-root
2020/05/29 09:11 upstream 75caf310d16c d19ed305 .config console log report ci-upstream-kasan-gce-root
2020/05/24 17:14 upstream caffb99b6929 bd28eb9d .config console log report ci-upstream-kasan-gce-root
2020/05/18 16:51 upstream b9bbe6ed63b2 684d3606 .config console log report ci-upstream-kasan-gce-selinux-root
2020/04/25 07:38 upstream b4f633221f0a 03d97a1b .config console log report ci-upstream-kasan-gce-root
2020/04/25 07:36 upstream b4f633221f0a 03d97a1b .config console log report ci-upstream-kasan-gce-selinux-root
2020/04/22 21:31 upstream 18bf34080c4c 2e44d63e .config console log report ci-upstream-kasan-gce-root
2020/04/14 18:27 upstream 8f3d9f354286 3f3c5574 .config console log report ci-upstream-kasan-gce-selinux-root
2020/04/14 18:19 linux-next f19bb13a0eaf 3f3c5574 .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.