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INFO: rcu detected stall in netlink_recvmsg (4)

Status: closed as invalid on 2025/10/29 00:33
Subsystems: net
[Documentation on labels]
First crash: 247d, last: 160d
Cause bisection: failed (error log, bisect log)
  
Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in netlink_recvmsg hardening mm 1 1 999d 999d 0/29 closed as invalid on 2023/06/13 18:27
upstream INFO: rcu detected stall in netlink_recvmsg (3) net 1 7 425d 668d 0/29 auto-obsoleted due to no activity on 2025/03/31 11:26
upstream INFO: rcu detected stall in netlink_recvmsg (5) net 1 C error error 2 54d 50d 0/29 upstream: reported C repro on 2026/01/09 23:32
upstream INFO: rcu detected stall in netlink_recvmsg (2) mm hardening 1 1 831d 831d 0/29 closed as invalid on 2024/02/01 10:31
Last patch testing requests (1)
Created Duration User Patch Repo Result
2025/10/09 17:14 20m retest repro upstream report log

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (2 ticks this GP) idle=4b24/1/0x4000000000000000 softirq=18978/18978 fqs=0
rcu: 	(detected by 1, t=10502 jiffies, g=13693, q=1545 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6012 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:118 [inline]
RIP: 0010:lock_acquire+0x94/0x360 kernel/locking/lockdep.c:5844
Code: 0f 84 d7 01 00 00 83 3d b9 69 06 0e 00 0f 84 f0 00 00 00 48 8b b4 24 90 00 00 00 4c 89 ef e8 b3 99 85 00 83 3d 9c 69 06 0e 00 <0f> 84 fa 00 00 00 65 8b 05 5f 82 03 11 85 c0 0f 85 eb 00 00 00 65
RSP: 0018:ffffc90000007c00 EFLAGS: 00000002
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 476dcd341c676400
RDX: 0000000000000000 RSI: ffffffff8b7cccf2 RDI: 1ffff110170c4f53
RBP: ffffffff81adc622 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1f474c7 R12: 0000000000000000
R13: ffff8880b8627a98 R14: 0000000000000000 R15: 0000000000000001
FS:  000055558a5c9500(0000) GS:ffff888125c15000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558b59c808 CR3: 000000007d010000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
 _raw_spin_lock_irq+0xa2/0xf0 kernel/locking/spinlock.c:170
 __run_hrtimer kernel/time/hrtimer.c:1765 [inline]
 __hrtimer_run_queues+0x602/0xc60 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
 __sysvec_apic_timer_interrupt+0x108/0x410 arch/x86/kernel/apic/apic.c:1056
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:check_kcov_mode kernel/kcov.c:194 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:246 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x37/0x90 kernel/kcov.c:314
Code: 08 b0 a0 92 65 8b 0d d8 ec e0 10 81 e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75 5b 83 ba 3c 16 00 00 00 74 52 8b 8a 18 16 00 00 <83> f9 03 75 47 48 8b 8a 20 16 00 00 44 8b 8a 1c 16 00 00 49 c1 e1
RSP: 0018:ffffc90004297b38 EFLAGS: 00000246
RAX: ffffffff89a1d358 RBX: ffff888032f18000 RCX: 0000000000000000
RDX: ffff888024c1bc00 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90004297c68 R08: ffff888032f18000 R09: 1ffff11006625800
R10: dffffc0000000000 R11: ffffffff89a1d2a0 R12: dffffc0000000000
R13: 0000000000000000 R14: 1ffff92000852f74 R15: ffff88807e289800
 netlink_recvmsg+0xb8/0xa30 net/netlink/af_netlink.c:1913
 sock_recvmsg_nosec net/socket.c:1065 [inline]
 sock_recvmsg+0x22c/0x270 net/socket.c:1087
 __sys_recvfrom+0x1f6/0x340 net/socket.c:2278
 __do_sys_recvfrom net/socket.c:2293 [inline]
 __se_sys_recvfrom net/socket.c:2289 [inline]
 __x64_sys_recvfrom+0xde/0x100 net/socket.c:2289
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb074390974
Code: 89 4c 24 1c e8 ed 5f 02 00 44 8b 54 24 1c 8b 3c 24 45 31 c9 89 c5 48 8b 54 24 10 48 8b 74 24 08 45 31 c0 b8 2d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 34 89 ef 48 89 04 24 e8 39 60 02 00 48 8b 04
RSP: 002b:00007fb0746ff680 EFLAGS: 00000246 ORIG_RAX: 000000000000002d
RAX: ffffffffffffffda RBX: 00007fb075104620 RCX: 00007fb074390974
RDX: 0000000000001000 RSI: 00007fb075104670 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fb075104670 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g13693 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=7244
rcu: rcu_preempt kthread starved for 10502 jiffies! g13693 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:26792 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7058
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
 kthread+0x70e/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x436/0x7d0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/12 19:45 upstream 320475fbd590 e2beed91 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: rcu detected stall in netlink_recvmsg
2025/09/22 09:19 upstream 07e27ad16399 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in netlink_recvmsg
2025/06/27 14:18 upstream 67a993863163 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in netlink_recvmsg
* Struck through repros no longer work on HEAD.