syzbot


INFO: rcu detected stall in chrdev_open (2)

Status: closed as invalid on 2022/02/08 10:45
Reported-by: syzbot+29784f46793e49c37812@syzkaller.appspotmail.com
First crash: 972d, last: 204d

Cause bisection: introduced by (bisect log) [merge commit]:
commit 801fc022147974f4754939202efe607294479bc9
Author: Thierry Reding <treding@nvidia.com>
Date: Fri Nov 18 13:34:46 2016 +0000

  Merge branch 'for-4.10/firmware' into for-4.10/reset

Crash: unregister_netdevice: waiting for DEV to become free (log)
Repro: C syz .config

Fix bisection: the fix commit could be any of (bisect log):
  ae4b064e2a61 Merge tag 'afs-fixes-20191211' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
  9e9fb7655ed5 Merge tag 'net-next-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
similar bugs (5):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: rcu detected stall in chrdev_open (2) 1 817d 817d 0/1 auto-closed as invalid on 2020/09/12 23:19
linux-4.14 INFO: rcu detected stall in chrdev_open C error 4 127d 232d 0/1 upstream: reported C repro on 2021/12/21 07:54
linux-4.19 INFO: rcu detected stall in chrdev_open (3) C error 16 125d 506d 0/1 upstream: reported C repro on 2021/03/22 19:09
linux-4.19 INFO: rcu detected stall in chrdev_open 1 950d 950d 0/1 auto-closed as invalid on 2020/05/02 02:53
upstream INFO: rcu detected stall in chrdev_open 4 980d 981d 0/23 closed as invalid on 2019/12/04 14:04

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
	(detected by 0, t=10502 jiffies, g=5689, q=83)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294997768-4294987266), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10502 jiffies! g5689 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:28688 pid:   14 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4972 [inline]
 __schedule+0xa9a/0x4940 kernel/sched/core.c:6253
 schedule+0xd2/0x260 kernel/sched/core.c:6326
 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881
 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1955
 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2128
 kthread+0x405/0x4f0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 3867 Comm: syz-executor808 Not tainted 5.16.0-rc4-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: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_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_check_gp_kthread_starvation.cold+0x1fb/0x200 kernel/rcu/tree_stall.h:481
 print_other_cpu_stall kernel/rcu/tree_stall.h:586 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:729 [inline]
 rcu_pending kernel/rcu/tree.c:3878 [inline]
 rcu_sched_clock_irq+0x2125/0x2200 kernel/rcu/tree.c:2597
 update_process_times+0x16d/0x200 kernel/time/timer.c:1785
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226
 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1428
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103
 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:tty_alloc_file drivers/tty/tty_io.c:191 [inline]
RIP: 0010:tty_open+0x164/0x1000 drivers/tty/tty_io.c:2140
Code: 00 e8 00 1e 85 fd 48 85 c0 48 89 c3 0f 84 bb 0c 00 00 e8 3f b5 3e fd 4d 8d af b0 01 00 00 4c 89 e8 48 c1 e8 03 42 80 3c 30 00 <0f> 85 7f 0c 00 00 49 89 9f b0 01 00 00 8b 5c 24 38 bf 00 00 50 00
RSP: 0018:ffffc90002c9f8c8 EFLAGS: 00000246
RAX: 1ffff1100edff266 RBX: ffff88807a891880 RCX: 0000000000000000
RDX: ffff8880731a3a00 RSI: ffffffff8438f601 RDI: 0000000000000000
RBP: 0000000000000000 R08: 000000002654bddb R09: 0000000031af7b9f
R10: 0000000000000001 R11: 0000000000000000 R12: 00000000fffffff5
R13: ffff888076ff9330 R14: dffffc0000000000 R15: ffff888076ff9180
 chrdev_open+0x266/0x770 fs/char_dev.c:414
 do_dentry_open+0x4c8/0x1250 fs/open.c:822
 do_open fs/namei.c:3426 [inline]
 path_openat+0x1cad/0x2750 fs/namei.c:3559
 do_filp_open+0x1aa/0x400 fs/namei.c:3586
 do_sys_openat2+0x16d/0x4d0 fs/open.c:1212
 do_sys_open fs/open.c:1228 [inline]
 __do_sys_openat fs/open.c:1244 [inline]
 __se_sys_openat fs/open.c:1239 [inline]
 __x64_sys_openat+0x13f/0x1f0 fs/open.c:1239
 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: 0033:0x7f6805a00af9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 15 00 00 90 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:00007f68059b2318 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f6805a883e8 RCX: 00007f6805a00af9
RDX: 0000000000000802 RSI: 0000000020000840 RDI: ffffffffffffff9c
RBP: 00007f6805a883e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 7974742f7665642f
R13: 00007ffc58b4f34f R14: 00007f68059b2400 R15: 0000000000022000
 </TASK>
sched: RT throttling activated
----------------
Code disassembly (best guess):
   0:	00 e8                	add    %ch,%al
   2:	00 1e                	add    %bl,(%rsi)
   4:	85 fd                	test   %edi,%ebp
   6:	48 85 c0             	test   %rax,%rax
   9:	48 89 c3             	mov    %rax,%rbx
   c:	0f 84 bb 0c 00 00    	je     0xccd
  12:	e8 3f b5 3e fd       	callq  0xfd3eb556
  17:	4d 8d af b0 01 00 00 	lea    0x1b0(%r15),%r13
  1e:	4c 89 e8             	mov    %r13,%rax
  21:	48 c1 e8 03          	shr    $0x3,%rax
  25:	42 80 3c 30 00       	cmpb   $0x0,(%rax,%r14,1)
* 2a:	0f 85 7f 0c 00 00    	jne    0xcaf <-- trapping instruction
  30:	49 89 9f b0 01 00 00 	mov    %rbx,0x1b0(%r15)
  37:	8b 5c 24 38          	mov    0x38(%rsp),%ebx
  3b:	bf 00 00 50 00       	mov    $0x500000,%edi

Crashes (55):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce-root 2021/12/11 21:03 upstream 6f513529296f 49ca1f59 .config log report syz C INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-root 2021/10/22 07:57 upstream 2f111a6fd5b5 55f90bc6 .config log report syz C INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-selinux-root 2021/10/21 07:22 upstream 8e37395c3a5d f111d03b .config log report syz C INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-selinux-root 2021/10/17 02:03 upstream 304040fb4909 0c5d9412 .config log report syz C INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-root 2021/10/12 10:28 upstream fa5878760579 838e7e2c .config log report syz C INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-selinux-root 2021/10/04 13:40 upstream 9e1ff307c779 ce697b49 .config log report syz C INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-selinux-root 2019/12/13 01:10 upstream ae4b064e2a61 08003f64 .config log report syz C
ci-upstream-kasan-gce-root 2019/12/12 15:53 upstream 687dec9b9459 d973f528 .config log report syz C
ci-upstream-kasan-gce-selinux-root 2021/12/27 06:32 upstream fc74e0a40e4f e4f103c4 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-selinux-root 2021/12/20 08:34 upstream a7904a538933 021b36cb .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-selinux-root 2021/12/16 13:46 upstream 2b14864acbaa 8dd6a5e3 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-selinux-root 2021/12/13 12:33 upstream 2585cf9dfaad 49ca1f59 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-root 2021/11/18 23:11 upstream 42eb8fdac2fc 31a30fc0 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-smack-root 2021/10/26 00:02 upstream c2b43854aad9 c1132b49 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-smack-root 2021/10/22 05:07 upstream 2f111a6fd5b5 55f90bc6 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-root 2021/10/22 03:17 upstream 2f111a6fd5b5 55f90bc6 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-smack-root 2021/10/21 13:37 upstream 2f111a6fd5b5 c5cb7da8 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-smack-root 2021/10/21 11:52 upstream 2f111a6fd5b5 f111d03b .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-selinux-root 2021/10/20 07:01 upstream d9abdee5fd5a 466b7db1 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-root 2021/10/19 18:24 upstream d9abdee5fd5a 466b7db1 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-smack-root 2021/10/17 10:27 upstream d999ade1cc86 0c5d9412 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-smack-root 2021/10/17 09:56 upstream d999ade1cc86 0c5d9412 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-root 2021/10/16 21:03 upstream 304040fb4909 0c5d9412 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-root 2021/10/15 23:48 upstream ec681c53f8d2 0c5d9412 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-root 2021/10/14 19:24 upstream 26d657410983 7aa5fe41 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-root 2021/10/14 15:52 upstream 26d657410983 5462d470 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-selinux-root 2021/10/14 15:18 upstream 26d657410983 5462d470 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-smack-root 2021/10/13 20:47 upstream 348949d9a444 5462d470 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-root 2021/10/09 16:40 upstream 717478d89fe2 838e7e2c .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-root 2021/10/09 11:14 upstream 5d6ab0bb408f 838e7e2c .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-selinux-root 2021/10/07 02:51 upstream 5af4055fa813 62ee0987 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-selinux-root 2021/10/07 02:39 upstream 5af4055fa813 62ee0987 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-root 2021/10/06 13:43 upstream 60a9483534ed 0a63fd36 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-selinux-root 2021/10/04 17:36 upstream 84b3e42564ac ce697b49 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-root 2021/04/29 19:00 upstream d2b6f8a17919 77e2b668 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-linux-next-kasan-gce-root 2022/01/18 06:22 linux-next 6f59bc242877 731a2d23 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-linux-next-kasan-gce-root 2021/12/14 07:41 linux-next ea922272cbe5 5d14b1ea .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-linux-next-kasan-gce-root 2021/10/18 09:40 linux-next 7c832d2f9b95 0c5d9412 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-linux-next-kasan-gce-root 2021/10/15 12:17 linux-next 7c832d2f9b95 0c5d9412 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-linux-next-kasan-gce-root 2021/10/13 22:49 linux-next 8006b911c90a 5462d470 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-linux-next-kasan-gce-root 2021/10/07 10:53 linux-next f8dc23b3dc0c 62ee0987 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-linux-next-kasan-gce-root 2021/10/06 19:30 linux-next 0dda5ee37364 62ee0987 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-linux-next-kasan-gce-root 2021/10/04 07:54 linux-next a25006a77348 ce697b49 .config log report info INFO: rcu detected stall in chrdev_open
ci-upstream-kasan-gce-root 2020/03/15 19:27 upstream d3dca69085e9 749688d2 .config log report
ci-upstream-kasan-gce-selinux-root 2020/03/12 06:05 upstream e3a36eb6dfae e7caca8e .config log report
ci-upstream-kasan-gce-smack-root 2020/02/11 17:01 upstream 0a679e13ea30 4d1ab643 .config log report
ci-upstream-kasan-gce-root 2020/02/05 09:44 upstream 6992ca0dd017 93e5e335 .config log report
ci-upstream-kasan-gce-selinux-root 2020/01/31 08:35 upstream 9f68e3655aae 5ed23f9a .config log report
ci-upstream-kasan-gce-root 2020/01/09 10:24 upstream b07f636fca1c ddc3e859 .config log report
ci-upstream-kasan-gce-smack-root 2020/01/08 12:35 upstream ae6088216ce4 6738e0b3 .config log report
ci-upstream-kasan-gce-root 2019/12/12 13:57 upstream 687dec9b9459 d973f528 .config log report
ci-upstream-linux-next-kasan-gce-root 2020/05/19 11:25 linux-next ac935d227366 6d882fd2 .config log report
ci-upstream-linux-next-kasan-gce-root 2020/05/13 12:24 linux-next ac935d227366 9a6d42fb .config log report
ci-upstream-linux-next-kasan-gce-root 2020/02/06 05:39 linux-next a0c61bf1c773 662cf49a .config log report