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INFO: rcu detected stall in ip_rcv

Status: auto-closed as invalid on 2019/10/25 14:11
Subsystems: netfilter
[Documentation on labels]
First crash: 2629d, last: 2466d
▶ ▼ Similar bugs (9)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in ip_rcv (7) net modules 1 3 128d 268d 0/29 auto-obsoleted due to no activity on 2026/03/20 17:26
linux-4.19 BUG: soft lockup in ip_rcv 1 C error 16 1151d 1819d 0/1 upstream: reported C repro on 2021/05/04 03:32
upstream INFO: rcu detected stall in ip_rcv (2) net 1 1 1973d 1973d 0/29 auto-closed as invalid on 2021/03/01 14:28
linux-4.14 INFO: rcu detected stall in ip_rcv (2) 1 1 1983d 1983d 0/1 auto-closed as invalid on 2021/03/20 21:11
upstream INFO: rcu detected stall in ip_rcv (6) netfilter 1 4 371d 515d 0/29 auto-obsoleted due to no activity on 2025/07/19 18:54
upstream INFO: rcu detected stall in ip_rcv (3) kernel 1 1 1835d 1835d 0/29 auto-closed as invalid on 2021/07/17 18:11
linux-4.14 INFO: rcu detected stall in ip_rcv 1 3 2164d 2183d 0/1 auto-closed as invalid on 2020/09/21 12:55
upstream INFO: rcu detected stall in ip_rcv (4) net bpf 1 12 1462d 1533d 0/29 auto-closed as invalid on 2022/07/25 09:18
upstream INFO: rcu detected stall in ip_rcv (5) net 1 2 976d 988d 0/29 auto-obsoleted due to no activity on 2023/11/23 01:36

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10500 ticks this GP) idle=3b6/1/0x4000000000000002 softirq=68735/68735 fqs=0 
rcu: 	 (t=10500 jiffies g=87893 q=2018)
rcu: rcu_preempt kthread starved for 10500 jiffies! g87893 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
rcu: RCU grace-period kthread stack dump:
rcu_preempt     I29024    10      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2844 [inline]
 __schedule+0x817/0x1cc0 kernel/sched/core.c:3485
 schedule+0x92/0x180 kernel/sched/core.c:3529
 schedule_timeout+0x4db/0xfd0 kernel/time/timer.c:1803
 rcu_gp_fqs_loop kernel/rcu/tree.c:1948 [inline]
 rcu_gp_kthread+0x956/0x17a0 kernel/rcu/tree.c:2105
 kthread+0x357/0x430 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
NMI backtrace for cpu 1
CPU: 1 PID: 12243 Comm: syz-executor.5 Not tainted 5.0.0-rc6+ #70
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1be/0x236 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x183/0x1cf kernel/rcu/tree.c:1211
 print_cpu_stall kernel/rcu/tree.c:1348 [inline]
 check_cpu_stall kernel/rcu/tree.c:1422 [inline]
 rcu_pending kernel/rcu/tree.c:3018 [inline]
 rcu_check_callbacks.cold+0x500/0xa4a kernel/rcu/tree.c:2521
 update_process_times+0x32/0x80 kernel/time/timer.c:1635
 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:161
 tick_sched_timer+0x47/0x130 kernel/time/tick-sched.c:1271
 __run_hrtimer kernel/time/hrtimer.c:1389 [inline]
 __hrtimer_run_queues+0x33e/0xde0 kernel/time/hrtimer.c:1451
 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1509
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1035 [inline]
 smp_apic_timer_interrupt+0x120/0x570 arch/x86/kernel/apic/apic.c:1060
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807
 </IRQ>
RIP: 0010:cpu_relax arch/x86/include/asm/processor.h:666 [inline]
RIP: 0010:virt_spin_lock arch/x86/include/asm/qspinlock.h:84 [inline]
RIP: 0010:native_queued_spin_lock_slowpath+0x132/0x970 kernel/locking/qspinlock.c:337
Code: 00 00 00 48 8b 45 d0 65 48 33 04 25 28 00 00 00 0f 85 a2 06 00 00 48 81 c4 98 00 00 00 5b 41 5c 41 5d 41 5e 41 5f 5d c3 f3 90 <e9> 73 ff ff ff 8b 45 98 4c 8d 65 d8 3d 00 01 00 00 0f 84 e5 00 00
RSP: 0018:ffff88808de1f078 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: ffffe8ffffd75f78 RCX: ffffffff8157bdc7
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffe8ffffd75f78
RBP: ffff88808de1f138 R08: 1ffffd1ffffaebef R09: fffff91ffffaebf0
R10: fffff91ffffaebef R11: ffffe8ffffd75f7b R12: 0000000000000001
R13: 0000000000000003 R14: fffff91ffffaebef R15: 00000000000001f8
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:653 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:50 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:90 [inline]
 do_raw_spin_lock+0x20e/0x2e0 kernel/locking/spinlock_debug.c:113
 __raw_spin_lock include/linux/spinlock_api_smp.h:143 [inline]
 _raw_spin_lock+0x37/0x40 kernel/locking/spinlock.c:144
 spin_lock include/linux/spinlock.h:329 [inline]
 nf_ct_add_to_unconfirmed_list net/netfilter/nf_conntrack_core.c:462 [inline]
 init_conntrack.isra.0+0xa15/0x1180 net/netfilter/nf_conntrack_core.c:1437
 resolve_normal_ct net/netfilter/nf_conntrack_core.c:1479 [inline]
 nf_conntrack_in+0xa68/0x1070 net/netfilter/nf_conntrack_core.c:1585
 ipv4_conntrack_in+0x1e/0x30 net/netfilter/nf_conntrack_proto.c:422
 nf_hook_entry_hookfn include/linux/netfilter.h:119 [inline]
 nf_hook_slow+0xbf/0x1f0 net/netfilter/core.c:511
 nf_hook include/linux/netfilter.h:244 [inline]
 NF_HOOK include/linux/netfilter.h:287 [inline]
 ip_rcv+0x237/0x3f0 net/ipv4/ip_input.c:524
 __netif_receive_skb_one_core+0x115/0x1a0 net/core/dev.c:4973
 __netif_receive_skb+0x2c/0x1c0 net/core/dev.c:5083
 netif_receive_skb_internal+0x117/0x660 net/core/dev.c:5186
 netif_receive_skb+0x6e/0x5a0 net/core/dev.c:5261
 tun_rx_batched.isra.0+0x4f7/0x840 drivers/net/tun.c:1562
 tun_get_user+0x2588/0x38d0 drivers/net/tun.c:1991
 tun_chr_write_iter+0xbd/0x160 drivers/net/tun.c:2019
 call_write_iter include/linux/fs.h:1863 [inline]
 do_iter_readv_writev+0x5e0/0x8e0 fs/read_write.c:680
 do_iter_write fs/read_write.c:956 [inline]
 do_iter_write+0x184/0x610 fs/read_write.c:937
 vfs_writev+0x1b3/0x2f0 fs/read_write.c:1001
 do_writev+0xf6/0x290 fs/read_write.c:1036
 __do_sys_writev fs/read_write.c:1109 [inline]
 __se_sys_writev fs/read_write.c:1106 [inline]
 __x64_sys_writev+0x75/0xb0 fs/read_write.c:1106
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457ce1
Code: 75 14 b8 14 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 e4 b9 fb ff c3 48 83 ec 08 e8 1a 2d 00 00 48 89 04 24 b8 14 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 63 2d 00 00 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00007f2bbaa4eba0 EFLAGS: 00000293 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 0000000000000032 RCX: 0000000000457ce1
RDX: 0000000000000001 RSI: 00007f2bbaa4ebf0 RDI: 00000000000000f0
RBP: 0000000020000000 R08: 00000000000000f0 R09: 0000000000000000
R10: 00007f2bbaa4f9d0 R11: 0000000000000293 R12: 00007f2bbaa4f6d4
R13: 00000000004c6477 R14: 00000000004db8c0 R15: 00000000ffffffff
rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 1-... } 11007 jiffies s: 5905 root: 0x2/.
rcu: blocking rcu_node structures:
Task dump for CPU 1:
syz-executor.5  R  running task    27360 12243   7780 0x8000000e
Call Trace:
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457ce1
Code: Bad RIP value.
RSP: 002b:00007f2bbaa4eba0 EFLAGS: 00000293 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 0000000000000032 RCX: 0000000000457ce1
RDX: 0000000000000001 RSI: 00007f2bbaa4ebf0 RDI: 00000000000000f0
RBP: 0000000020000000 R08: 00000000000000f0 R09: 0000000000000000
R10: 00007f2bbaa4f9d0 R11: 0000000000000293 R12: 00007f2bbaa4f6d4
R13: 00000000004c6477 R14: 00000000004db8c0 R15: 00000000ffffffff

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/02/14 01:05 upstream 1f947a7a011f 0a49c954 .config console log report ci-upstream-kasan-gce
2019/07/27 01:06 linux-next fde50b96be82 c85e1c5b .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.