syzbot


INFO: task hung in nsim_fib_destroy (2)

Status: closed as invalid on 2022/02/08 09:50
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 323d, last: 323d
similar bugs (2):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in nsim_fib_destroy (3) 1 104d 104d 0/24 auto-obsoleted due to no activity on 2022/11/15 10:21
upstream INFO: task hung in nsim_fib_destroy 1 413d 413d 0/24 auto-closed as invalid on 2022/01/09 18:53

Sample crash report:
INFO: task syz-executor.5:19810 blocked for more than 143 seconds.
      Not tainted 5.16.0-rc8-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.5  state:D stack:25312 pid:19810 ppid:  3636 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4972 [inline]
 __schedule+0xa9a/0x4900 kernel/sched/core.c:6253
 schedule+0xd2/0x260 kernel/sched/core.c:6326
 schedule_timeout+0x1db/0x2a0 kernel/time/timer.c:1857
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x174/0x270 kernel/sched/completion.c:138
 __flush_work+0x56c/0xb10 kernel/workqueue.c:3084
 nsim_fib_destroy+0x8c/0x1a0 drivers/net/netdevsim/fib.c:1618
 nsim_dev_reload_destroy+0x191/0x300 drivers/net/netdevsim/dev.c:1653
 nsim_dev_reload_down+0xdf/0x180 drivers/net/netdevsim/dev.c:964
 devlink_reload+0x53b/0x6b0 net/core/devlink.c:4072
 devlink_nl_cmd_reload+0x57f/0x1280 net/core/devlink.c:4193
 genl_family_rcv_msg_doit+0x228/0x320 net/netlink/genetlink.c:731
 genl_family_rcv_msg net/netlink/genetlink.c:775 [inline]
 genl_rcv_msg+0x328/0x580 net/netlink/genetlink.c:792
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494
 genl_rcv+0x24/0x40 net/netlink/genetlink.c:803
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x904/0xdf0 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:725
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2413
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2467
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2496
 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+0x44/0xae
RIP: 0033:0x7ff94f954e99
RSP: 002b:00007ff94e2a9168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007ff94fa68030 RCX: 00007ff94f954e99
RDX: 0000000000000000 RSI: 00000000200003c0 RDI: 0000000000000005
RBP: 00007ff94f9aeff1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff9de74f3f R14: 00007ff94e2a9300 R15: 0000000000022000
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8bb83da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458
2 locks held by kworker/u4:4/513:
 #0: ffff8880b9d39a98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2b/0x120 kernel/sched/core.c:478
 #1: ffff8880b9d279c8 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x173/0x490 kernel/sched/psi.c:871
2 locks held by getty/3286:
 #0: ffff88814aa19098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002b962e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2113
3 locks held by kworker/1:3/10261:
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:635 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:662 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x896/0x1660 kernel/workqueue.c:2269
 #1: ffffc900047a7db0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1660 kernel/workqueue.c:2273
 #2: ffff888031ca0240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x1b9/0x2490 drivers/net/netdevsim/fib.c:1474
4 locks held by syz-executor.5/19810:
 #0: ffffffff8d3a95f0 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802
 #1: ffffffff8d3a96a8 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
 #1: ffffffff8d3a96a8 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x3e0/0x580 net/netlink/genetlink.c:790
 #2: ffffffff8d343388 (devlink_mutex){+.+.}-{3:3}, at: devlink_nl_pre_doit+0x2b/0xa00 net/core/devlink.c:607
 #3: ffff88804f0a65c0 (&nsim_bus_dev->nsim_bus_reload_lock){+.+.}-{3:3}, at: nsim_dev_reload_down+0x4d/0x180 drivers/net/netdevsim/dev.c:951

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.16.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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+0x47/0x144 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
 watchdog+0xc1d/0xf50 kernel/hung_task.c:295
 kthread+0x405/0x4f0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 513 Comm: kworker/u4:4 Not tainted 5.16.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
RIP: 0010:check_region_inline mm/kasan/generic.c:170 [inline]
RIP: 0010:kasan_check_range+0x12c/0x180 mm/kasan/generic.c:189
Code: 00 74 ef 49 8d 04 2c 48 85 d2 75 0b 48 89 da 48 29 c2 e9 55 ff ff ff 49 39 d2 75 17 49 0f be 02 41 83 e1 07 49 39 c1 7d 0a 5b <b8> 01 00 00 00 5d 41 5c c3 44 89 c2 e8 53 ef ff ff 5b 83 f0 01 5d
RSP: 0018:ffffc9000326f660 EFLAGS: 00000046
RAX: fffffbfff1ff3741 RBX: 0000000000000036 RCX: ffffffff815c6155
RDX: fffffbfff1ff3741 RSI: 0000000000000008 RDI: ffffffff8ff9ba00
RBP: fffffbfff1ff3740 R08: 0000000000000000 R09: ffffffff8ff9ba07
R10: fffffbfff1ff3740 R11: 0000000000000001 R12: ffff8880193da7d8
R13: ffff8880193d9d00 R14: ffffffff8d924308 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f70ac94d990 CR3: 0000000013390000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 hlock_class kernel/locking/lockdep.c:199 [inline]
 lookup_chain_cache_add kernel/locking/lockdep.c:3713 [inline]
 validate_chain kernel/locking/lockdep.c:3769 [inline]
 __lock_acquire+0x1655/0x5470 kernel/locking/lockdep.c:5027
 lock_acquire kernel/locking/lockdep.c:5637 [inline]
 lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
 rcu_note_context_switch+0x2ea/0x17c0 kernel/rcu/tree_plugin.h:322
 __schedule+0x238/0x4900 kernel/sched/core.c:6150
 preempt_schedule_irq+0x4e/0x90 kernel/sched/core.c:6668
 irqentry_exit+0x31/0x80 kernel/entry/common.c:425
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:lock_acquire+0x1ef/0x510 kernel/locking/lockdep.c:5605
Code: c6 a5 7e 83 f8 01 0f 85 b4 02 00 00 9c 58 f6 c4 02 0f 85 9f 02 00 00 48 83 7c 24 08 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24
RSP: 0018:ffffc9000326fb30 EFLAGS: 00000206
RAX: dffffc0000000000 RBX: 1ffff9200064df68 RCX: d950c196984fa138
RDX: 1ffff1100327b4eb RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8ff9ba07
R10: fffffbfff1ff3740 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: ffffffff8bb83da0 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:268 [inline]
 rcu_read_lock include/linux/rcupdate.h:688 [inline]
 batadv_nc_process_nc_paths.part.0+0xec/0x3c0 net/batman-adv/network-coding.c:687
 batadv_nc_process_nc_paths net/batman-adv/network-coding.c:679 [inline]
 batadv_nc_worker+0xce4/0xfa0 net/batman-adv/network-coding.c:735
 process_one_work+0x9b2/0x1660 kernel/workqueue.c:2298
 worker_thread+0x65d/0x1130 kernel/workqueue.c:2445
 kthread+0x405/0x4f0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
----------------
Code disassembly (best guess):
   0:	00 74 ef 49          	add    %dh,0x49(%rdi,%rbp,8)
   4:	8d 04 2c             	lea    (%rsp,%rbp,1),%eax
   7:	48 85 d2             	test   %rdx,%rdx
   a:	75 0b                	jne    0x17
   c:	48 89 da             	mov    %rbx,%rdx
   f:	48 29 c2             	sub    %rax,%rdx
  12:	e9 55 ff ff ff       	jmpq   0xffffff6c
  17:	49 39 d2             	cmp    %rdx,%r10
  1a:	75 17                	jne    0x33
  1c:	49 0f be 02          	movsbq (%r10),%rax
  20:	41 83 e1 07          	and    $0x7,%r9d
  24:	49 39 c1             	cmp    %rax,%r9
  27:	7d 0a                	jge    0x33
  29:	5b                   	pop    %rbx
* 2a:	b8 01 00 00 00       	mov    $0x1,%eax <-- trapping instruction
  2f:	5d                   	pop    %rbp
  30:	41 5c                	pop    %r12
  32:	c3                   	retq
  33:	44 89 c2             	mov    %r8d,%edx
  36:	e8 53 ef ff ff       	callq  0xffffef8e
  3b:	5b                   	pop    %rbx
  3c:	83 f0 01             	xor    $0x1,%eax
  3f:	5d                   	pop    %rbp

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-net-kasan-gce 2022/01/09 21:35 net-next d5c8725cc913 2ca0d385 .config log report info INFO: task hung in nsim_fib_destroy
* Struck through repros no longer work on HEAD.