syzbot


INFO: task hung in io_uring_register (2)

Status: auto-obsoleted due to no activity on 2023/01/17 13:12
Subsystems: io-uring
[Documentation on labels]
First crash: 537d, last: 537d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in io_uring_register fs 1 847d 847d 0/26 auto-closed as invalid on 2022/04/01 07:34
upstream INFO: task hung in io_uring_register (3) io-uring syz error error 2 397d 393d 0/26 auto-obsoleted due to no activity on 2023/06/25 17:40

Sample crash report:
INFO: task syz-executor.0:24965 blocked for more than 143 seconds.
      Not tainted 6.0.0-syzkaller-06475-g4c86114194e6 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0  state:D stack:26224 pid:24965 ppid: 24951 flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5183 [inline]
 __schedule+0xadf/0x52b0 kernel/sched/core.c:6495
 schedule+0xda/0x1b0 kernel/sched/core.c:6571
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6630
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0xa44/0x1350 kernel/locking/mutex.c:747
 __do_sys_io_uring_register+0x1d4/0x1230 io_uring/io_uring.c:3879
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f0d9548a5a9
RSP: 002b:00007f0d96523168 EFLAGS: 00000246 ORIG_RAX: 00000000000001ab
RAX: ffffffffffffffda RBX: 00007f0d955abf80 RCX: 00007f0d9548a5a9
RDX: 00000000200002c0 RSI: 0000000000000006 RDI: 0000000000000003
RBP: 00007f0d954e5580 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe4a376c3f R14: 00007f0d96523300 R15: 0000000000022000
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8bf82df0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x26/0xc70 kernel/rcu/tasks.h:507
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8bf82af0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x26/0xc70 kernel/rcu/tasks.h:507
1 lock held by khungtaskd/28:
 #0: ffffffff8bf83940 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6492
2 locks held by getty/3290:
 #0: ffff88814b519098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244
 #1: ffffc900020182f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xef0/0x13e0 drivers/tty/n_tty.c:2177
3 locks held by kworker/u4:12/5293:
3 locks held by kworker/0:1/11038:
 #0: ffff888011867d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888011867d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888011867d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline]
 #0: ffff888011867d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline]
 #0: ffff888011867d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline]
 #0: ffff888011867d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260
 #1: ffffc900155dfda8 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264
 #2: ffff8880725c4240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x1d1/0x24a0 drivers/net/netdevsim/fib.c:1489
2 locks held by syz-executor.0/24889:
1 lock held by syz-executor.0/24965:
 #0: ffff88808f10b0a8 (&ctx->uring_lock){+.+.}-{3:3}, at: __do_sys_io_uring_register+0x1d4/0x1230 io_uring/io_uring.c:3879
2 locks held by syz-executor.0/24966:
2 locks held by syz-executor.0/25386:

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.0.0-syzkaller-06475-g4c86114194e6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x46/0x14f lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x206/0x250 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xc18/0xf50 kernel/hung_task.c:369
 kthread+0x2e4/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 25459 Comm: syz-executor.0 Not tainted 6.0.0-syzkaller-06475-g4c86114194e6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
RIP: 0010:hlock_class kernel/locking/lockdep.c:239 [inline]
RIP: 0010:mark_lock.part.0+0xfc/0x1910 kernel/locking/lockdep.c:4610
Code: 0f b7 f2 be 08 00 00 00 4c 89 f0 48 c1 e8 06 48 8d 3c c5 40 79 90 90 e8 52 71 69 00 4c 0f a3 35 4a 58 33 0f 0f 83 cd 00 00 00 <4b> 8d 04 76 48 c1 e0 06 48 05 60 7d 90 90 48 8d 78 50 48 ba 00 00
RSP: 0018:ffffc90003756e88 EFLAGS: 00000047
RAX: 0000000000000001 RBX: 1ffff920006eadd8 RCX: ffffffff815d20ee
RDX: fffffbfff2120f29 RSI: 0000000000000008 RDI: ffffffff90907940
RBP: 0000000000000200 R08: 0000000000000000 R09: ffffffff90907947
R10: fffffbfff2120f28 R11: 0000000000000000 R12: ffff88809e27caa0
R13: 0000000000000009 R14: 000000000000002c R15: ffff88809e27cac0
FS:  00007f0daf8d6700(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0dae7a049c CR3: 000000009f4b3000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 mark_lock kernel/locking/lockdep.c:4596 [inline]
 mark_usage kernel/locking/lockdep.c:4553 [inline]
 __lock_acquire+0x8ab/0x56d0 kernel/locking/lockdep.c:5007
 lock_acquire kernel/locking/lockdep.c:5666 [inline]
 lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5631
 rcu_lock_acquire include/linux/rcupdate.h:304 [inline]
 rcu_read_lock include/linux/rcupdate.h:738 [inline]
 folio_evictable+0x38/0x230 mm/internal.h:135
 move_pages_to_lru+0x227/0x1150 mm/vmscan.c:2334
 shrink_inactive_list mm/vmscan.c:2450 [inline]
 shrink_list mm/vmscan.c:2674 [inline]
 shrink_lruvec+0xcfd/0x2650 mm/vmscan.c:2991
 shrink_node_memcgs mm/vmscan.c:3180 [inline]
 shrink_node+0x85e/0x1e80 mm/vmscan.c:3304
 shrink_zones mm/vmscan.c:3542 [inline]
 do_try_to_free_pages+0x3b4/0x17a0 mm/vmscan.c:3601
 try_to_free_mem_cgroup_pages+0x364/0x960 mm/vmscan.c:3916
 reclaim_high.constprop.0+0x182/0x230 mm/memcontrol.c:2335
 mem_cgroup_handle_over_high+0x18c/0x510 mm/memcontrol.c:2520
 try_charge_memcg+0xe7b/0x13f0 mm/memcontrol.c:2758
 obj_cgroup_charge_pages mm/memcontrol.c:3040 [inline]
 __memcg_kmem_charge_page+0x16a/0x3b0 mm/memcontrol.c:3066
 __alloc_pages+0x1ef/0x510 mm/page_alloc.c:5566
 alloc_pages+0x1a6/0x270 mm/mempolicy.c:2270
 __get_free_pages+0x8/0x40 mm/page_alloc.c:5598
 io_allocate_scq_urings io_uring/io_uring.c:3147 [inline]
 io_uring_create io_uring/io_uring.c:3316 [inline]
 io_uring_setup.cold+0x115c/0x1a54 io_uring/io_uring.c:3414
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f0dae68a5a9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0daf8d60e8 EFLAGS: 00000206 ORIG_RAX: 00000000000001a9
RAX: ffffffffffffffda RBX: 00007f0dae7abf80 RCX: 00007f0dae68a5a9
RDX: 0000000020ffe000 RSI: 0000000020000240 RDI: 0000000000003ede
RBP: 0000000020000240 R08: 0000000020000140 R09: 0000000020000140
R10: 0000000020000100 R11: 0000000000000206 R12: 0000000020000140
R13: 0000000020ffe000 R14: 0000000020000100 R15: 0000000020002000
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/10/08 08:01 upstream 4c86114194e6 0de35f24 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: task hung in io_uring_register
* Struck through repros no longer work on HEAD.