syzbot


INFO: rcu detected stall in proc_reg_read (2)

Status: closed as invalid on 2019/12/04 14:14
Subsystems: kernel
[Documentation on labels]
First crash: 1617d, last: 1615d
Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in proc_reg_read mm 6 1964d 2043d 0/26 closed as dup on 2019/01/02 16:24
upstream INFO: rcu detected stall in proc_reg_read (5) fs 1 1355d 1355d 0/26 auto-closed as invalid on 2020/11/18 23:09
upstream INFO: rcu detected stall in proc_reg_read (6) fs 1 1098d 1098d 0/26 auto-closed as invalid on 2021/08/03 06:54
linux-4.19 INFO: rcu detected stall in proc_reg_read syz error 11 479d 1205d 0/1 upstream: reported syz repro on 2021/01/17 20:31
upstream INFO: rcu detected stall in proc_reg_read (4) kernel 9 1580d 1581d 0/26 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in proc_reg_read (3) kernel 3 1581d 1581d 0/26 closed as invalid on 2020/01/08 05:23

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
	(detected by 1, t=10502 jiffies, g=6033, q=39)
rcu: All QSes seen, last rcu_preempt kthread activity 10503 (4294953475-4294942972), jiffies_till_next_fqs=1, root ->qsmask 0x0
rsyslogd        R  running task    28512  7940      1 0x0000400a
Call Trace:
 <IRQ>
 sched_show_task+0x40f/0x560 kernel/sched/core.c:5954
 print_other_cpu_stall kernel/rcu/tree_stall.h:410 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:538 [inline]
 rcu_pending kernel/rcu/tree.c:2827 [inline]
 rcu_sched_clock_irq+0x1861/0x1ad0 kernel/rcu/tree.c:2271
 update_process_times+0x12d/0x180 kernel/time/timer.c:1726
 tick_sched_handle kernel/time/tick-sched.c:167 [inline]
 tick_sched_timer+0x263/0x420 kernel/time/tick-sched.c:1310
 __run_hrtimer kernel/time/hrtimer.c:1517 [inline]
 __hrtimer_run_queues+0x403/0x840 kernel/time/hrtimer.c:1579
 hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1641
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
 smp_apic_timer_interrupt+0x109/0x280 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:mod_memcg_page_state+0x168/0x190 include/linux/memcontrol.h:655
Code: c7 28 95 0a 89 e8 a8 9a 69 00 48 83 3d c8 20 c2 07 00 74 2d e8 19 25 2e 00 4c 89 ff 57 9d 0f 1f 44 00 00 5b 41 5c 41 5e 41 5f <5d> c3 e8 01 25 2e 00 0f 0b e8 fa 24 2e 00 0f 0b e8 f3 24 2e 00 0f
RSP: 0018:ffffc90001a47a50 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13
RAX: ffffffff81487433 RBX: ffff88806c7faf08 RCX: ffff888094ef4580
RDX: 0000000000000000 RSI: 00000000fffffffc RDI: ffffea0001b1ff00
RBP: ffffc90001a47a50 R08: dffffc0000000000 R09: fffffbfff1287a8d
R10: fffffbfff1287a8d R11: 0000000000000000 R12: ffff88806c7fafa0
R13: dffffc0000000000 R14: 1ffff1100d8ff5f4 R15: ffff8880a8237528
 free_thread_stack+0x168/0x590 kernel/fork.c:280
 release_task_stack kernel/fork.c:440 [inline]
 put_task_stack+0xa3/0x130 kernel/fork.c:451
 finish_task_switch+0x3f1/0x550 kernel/sched/core.c:3256
 context_switch kernel/sched/core.c:3388 [inline]
 __schedule+0x9a8/0xcc0 kernel/sched/core.c:4081
 schedule+0x181/0x210 kernel/sched/core.c:4155
 do_syslog+0xdc7/0x1740 kernel/printk/printk.c:1525
 kmsg_read+0x94/0xd0 fs/proc/kmsg.c:40
 proc_reg_read+0x1e2/0x2d0 fs/proc/inode.c:223
 __vfs_read+0xb8/0x730 fs/read_write.c:425
 vfs_read+0x1dd/0x420 fs/read_write.c:461
 ksys_read+0x117/0x220 fs/read_write.c:587
 __do_sys_read fs/read_write.c:597 [inline]
 __se_sys_read fs/read_write.c:595 [inline]
 __x64_sys_read+0x7b/0x90 fs/read_write.c:595
 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fd8bc3031fd
Code: d1 20 00 00 75 10 b8 00 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 5e fa ff ff 48 89 04 24 b8 00 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 a7 fa ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00007fd8b98a2e30 EFLAGS: 00000293 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00000000009a3170 RCX: 00007fd8bc3031fd
RDX: 0000000000000fff RSI: 00007fd8bb0d75a0 RDI: 0000000000000004
RBP: 0000000000000000 R08: 000000000098e260 R09: 0000000004000001
R10: 0000000000000001 R11: 0000000000000293 R12: 000000000065e420
R13: 00007fd8b98a39c0 R14: 00007fd8bc948040 R15: 0000000000000003
rcu: rcu_preempt kthread starved for 10535 jiffies! g6033 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    29032    10      2 0x80004000
Call Trace:
 context_switch kernel/sched/core.c:3385 [inline]
 __schedule+0x9a0/0xcc0 kernel/sched/core.c:4081
 schedule+0x181/0x210 kernel/sched/core.c:4155
 schedule_timeout+0x14f/0x240 kernel/time/timer.c:1895
 rcu_gp_fqs_loop kernel/rcu/tree.c:1661 [inline]
 rcu_gp_kthread+0xed8/0x1770 kernel/rcu/tree.c:1821
 kthread+0x332/0x350 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

Crashes (36):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/12/04 12:23 upstream 63de37476ebd 0ecb9746 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 10:03 upstream 63de37476ebd 0ecb9746 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 09:02 upstream 63de37476ebd 0ecb9746 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 06:54 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 03:51 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 01:52 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/04 01:29 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 23:52 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 23:32 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 23:12 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 23:11 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 21:55 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 21:51 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 17:52 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 17:50 upstream 76bb8b05960c ae13a849 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 15:20 upstream 76bb8b05960c ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 14:10 upstream 76bb8b05960c ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 13:24 upstream 76bb8b05960c ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 12:37 upstream 76bb8b05960c ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 11:08 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 10:36 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 09:39 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 09:24 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 09:10 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 09:03 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 05:15 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 04:49 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 02:55 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 01:32 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/03 01:25 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/02 22:51 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/02 22:32 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/02 21:27 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/02 20:53 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/02 20:43 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
2019/12/02 20:42 upstream 596cf45cbf6e ab342da3 .config console log report ci-upstream-kasan-gce-smack-root
* Struck through repros no longer work on HEAD.