INFO: rcu detected stall in sys_exit_group (2)

Status: auto-obsoleted due to no activity on 2023/12/07 20:57
Reported-by: syzbot+d379c331ad4ccc35fac3@syzkaller.appspotmail.com
First crash: 1065d, last: 1065d
▶ ▼ Similar bugs (17)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_exit_group (7) net 1 syz, C unreliable inconclusive 90 752d 1748d 0/29 upstream: reported C repro on 2021/10/15 18:41
upstream INFO: rcu detected stall in sys_exit_group (6) mm 1 syz, C 4 2128d 2134d 19/29 fixed on 2021/03/10 01:48
linux-5.15 INFO: rcu detected stall in sys_exit_group (2) 1 3 833d 867d 0/3 auto-obsoleted due to no activity on 2024/07/27 04:53
linux-6.1 INFO: rcu detected stall in sys_exit_group (3) origin:upstream 1 syz, C error 34 12d 918d 0/3 upstream: reported C repro on 2024/01/23 11:05
linux-6.1 INFO: rcu detected stall in sys_exit_group 1 1 1176d 1176d 0/3 auto-obsoleted due to no activity on 2023/08/23 09:06
linux-5.15 INFO: rcu detected stall in sys_exit_group 1 1 1127d 1127d 0/3 auto-obsoleted due to no activity on 2023/10/06 21:30
upstream INFO: rcu detected stall in sys_exit_group (2) mm cgroups 1 56 2429d 2431d 0/29 closed as invalid on 2019/12/04 14:14
linux-6.6 INFO: rcu detected stall in sys_exit_group origin:upstream 1 syz, C error 16 26d 373d 0/2 upstream: reported C repro on 2025/07/21 16:02
upstream INFO: rcu detected stall in sys_exit_group (3) mm 1 8 2395d 2395d 0/29 closed as invalid on 2020/01/08 05:23
upstream INFO: rcu detected stall in sys_exit_group (4) mm 1 13 2394d 2395d 0/29 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in sys_exit_group (5) mm 1 1 2316d 2316d 0/29 auto-closed as invalid on 2020/06/25 07:58
linux-5.15 INFO: rcu detected stall in sys_exit_group (3) 1 2 622d 655d 0/3 auto-obsoleted due to no activity on 2025/02/22 19:05
linux-5.15 INFO: rcu detected stall in sys_exit_group (4) origin:upstream 1 syz, C error 8 62d 314d 0/3 upstream: reported C repro on 2025/09/19 02:54
upstream INFO: rcu detected stall in sys_exit_group kernel 1 syz, C done 1 2510d 2506d 13/29 fixed on 2019/10/09 10:54
android-5-10 BUG: soft lockup in sys_exit_group 1 1 738d 738d 0/2 auto-obsoleted due to no activity on 2024/10/19 10:22
android-5-10 BUG: soft lockup in sys_exit_group (2) 1 1 181d 181d 0/2 auto-obsoleted due to no activity on 2026/04/29 20:43
android-5-15 BUG: soft lockup in sys_exit_group 1 syz, C error 7 700d 843d 0/2 auto-obsoleted due to no activity on 2024/12/07 01:30

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P2967/1:b..l
	(detected by 1, t=10502 jiffies, g=39657, q=125 ncpus=2)
task:udevd           state:R  running task     stack:22120 pid:2967  ppid:1      flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x132c/0x4330 kernel/sched/core.c:6554
 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6723
 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6747
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0x128/0x130 kernel/locking/spinlock.c:194
 spin_unlock_irqrestore include/linux/spinlock.h:405 [inline]
 __wake_up_common_lock kernel/sched/wait.c:140 [inline]
 __wake_up_sync_key+0x121/0x1c0 kernel/sched/wait.c:208
 sock_def_readable+0x135/0x240 net/core/sock.c:3290
 __netlink_sendskb net/netlink/af_netlink.c:1275 [inline]
 netlink_sendskb+0x8e/0x120 net/netlink/af_netlink.c:1281
 netlink_unicast+0x3a1/0x990 net/netlink/af_netlink.c:1369
 netlink_sendmsg+0xa26/0xd60 net/netlink/af_netlink.c:1903
 sock_sendmsg_nosec net/socket.c:716 [inline]
 sock_sendmsg net/socket.c:736 [inline]
 ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2482
 ___sys_sendmsg net/socket.c:2536 [inline]
 __sys_sendmsg+0x2a9/0x390 net/socket.c:2565
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f8302d86a4b
RSP: 002b:00007ffcf5d52298 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00005611aeee2df0 RCX: 00007f8302d86a4b
RDX: 0000000000000000 RSI: 00007ffcf5d522a8 RDI: 0000000000000004
RBP: 00005611aef01940 R08: 0000000000000001 R09: 0000000000000000
R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000000a7 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g39657 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=32524
rcu: rcu_preempt kthread starved for 10502 jiffies! g39657 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:26656 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x132c/0x4330 kernel/sched/core.c:6554
 schedule+0xbf/0x180 kernel/sched/core.c:6630
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1935
 rcu_gp_fqs_loop+0x2c2/0x1010 kernel/rcu/tree.c:1661
 rcu_gp_kthread+0xa3/0x3a0 kernel/rcu/tree.c:1860
 kthread+0x26e/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 9547 Comm: syz-executor.3 Not tainted 6.1.49-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
RIP: 0010:rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:122 [inline]
RIP: 0010:rcu_is_watching+0x22/0xb0 kernel/rcu/tree.c:720
Code: ff ff ff e8 80 18 12 09 41 57 41 56 53 65 ff 05 5c 82 8f 7e e8 bf 30 12 09 89 c3 83 f8 08 73 76 49 bf 00 00 00 00 00 fc ff df <4c> 8d 34 dd 50 08 b9 8c 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 74 08
RSP: 0018:ffffc900000079e0 EFLAGS: 00000093
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8169ed5b
RDX: 0000000000000000 RSI: ffffffff8b3cea80 RDI: ffffffff8b3cea40
RBP: ffffc90000007b48 R08: dffffc0000000000 R09: fffffbfff1ce7066
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000000f48
R13: dffffc0000000000 R14: 0000000000000000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000000ce8e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 trace_lock_acquire include/trace/events/lock.h:24 [inline]
 lock_acquire+0xfa/0x5a0 kernel/locking/lockdep.c:5640
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
 debug_object_activate+0x16a/0x890 lib/debugobjects.c:706
 debug_hrtimer_activate kernel/time/hrtimer.c:420 [inline]
 debug_activate kernel/time/hrtimer.c:475 [inline]
 enqueue_hrtimer+0x30/0x390 kernel/time/hrtimer.c:1084
 __run_hrtimer kernel/time/hrtimer.c:1702 [inline]
 __hrtimer_run_queues+0x728/0xe50 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0x156/0x580 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5673
Code: 2b 00 74 08 4c 89 f7 e8 6f a5 76 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc900166ff460 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff92002cdfe98 RCX: 1ffff92002cdfe38
RDX: dffffc0000000000 RSI: ffffffff8aebf420 RDI: ffffffff8b3ceaa0
RBP: ffffc900166ff5c0 R08: dffffc0000000000 R09: fffffbfff2093445
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92002cdfe94
R13: dffffc0000000000 R14: ffffc900166ff4c0 R15: 0000000000000246
 rcu_lock_acquire+0x20/0x30 include/linux/rcupdate.h:306
 rcu_read_lock include/linux/rcupdate.h:747 [inline]
 folio_memcg_lock+0x83/0x360 mm/memcontrol.c:2098
 page_remove_rmap+0x2e/0xed0 mm/rmap.c:1426
 zap_pte_range mm/memory.c:1443 [inline]
 zap_pmd_range mm/memory.c:1564 [inline]
 zap_pud_range mm/memory.c:1593 [inline]
 zap_p4d_range mm/memory.c:1614 [inline]
 unmap_page_range+0x1217/0x2740 mm/memory.c:1635
 unmap_vmas+0x3c4/0x560 mm/memory.c:1720
 exit_mmap+0x252/0x9f0 mm/mmap.c:3214
 __mmput+0x115/0x3c0 kernel/fork.c:1191
 exit_mm+0x226/0x300 kernel/exit.c:563
 do_exit+0x67e/0x2300 kernel/exit.c:856
 do_group_exit+0x202/0x2b0 kernel/exit.c:1019
 __do_sys_exit_group kernel/exit.c:1030 [inline]
 __se_sys_exit_group kernel/exit.c:1028 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1028
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f934547cae9
Code: Unable to access opcode bytes at 0x7f934547cabf.
RSP: 002b:00007ffe634dd388 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 000000000000001e RCX: 00007f934547cae9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000001 R08: 0000000000000504 R09: 0000000000000000
R10: 0000001b31620000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000001
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/08/29 20:57 linux-6.1.y 024f76bca9d0 ce731e62 .config console log report info ci2-linux-6-1-kasan INFO: rcu detected stall in sys_exit_group
* Struck through repros no longer work on HEAD.