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INFO: rcu detected stall in rtnl_dumpit (2)

Status: auto-obsoleted due to no activity on 2025/10/29 04:14
Subsystems: net
[Documentation on labels]
First crash: 183d, last: 183d
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in rtnl_dumpit net 1 1 474d 474d 0/29 auto-obsoleted due to no activity on 2025/01/11 15:14

Sample crash report:
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 ticks this GP) idle=ab64/1/0x4000000000000000 softirq=54066/54066 fqs=0
rcu: 	(detected by 1, t=10502 jiffies, g=39773, q=1120 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 13642 Comm: syz.2.2135 Not tainted 6.16.0-syzkaller-06574-gd9104cec3e8f #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:arch_irqs_disabled_flags arch/x86/include/asm/irqflags.h:146 [inline]
RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:153 [inline]
RIP: 0010:lock_is_held_type+0x11c/0x190 kernel/locking/lockdep.c:5942
Code: 48 c7 c7 8b 5e b6 8d e8 92 16 00 00 b8 ff ff ff ff 65 0f c1 05 35 73 2a 07 83 f8 01 75 44 48 c7 04 24 00 00 00 00 9c 8f 04 24 <f7> 04 24 00 02 00 00 75 4c 41 f7 c4 00 02 00 00 74 01 fb 65 48 8b
RSP: 0018:ffffc90000007c28 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000001 RCX: 06f9850805073d00
RDX: ffff888058100000 RSI: ffffffff8db65e8b RDI: ffffffff8be30a00
RBP: 00000000ffffffff R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000f7c R12: 0000000000000046
R13: ffff888058100000 R14: ffff88807489f300 R15: 0000000000000002
FS:  00007f0dfff546c0(0000) GS:ffff888125c80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30420220 CR3: 000000006a7ce000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 lock_is_held include/linux/lockdep.h:249 [inline]
 advance_sched+0x160/0xc90 net/sched/sch_taprio.c:927
 __run_hrtimer kernel/time/hrtimer.c:1761 [inline]
 __hrtimer_run_queues+0x52c/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:instrument_atomic_read include/linux/instrumented.h:68 [inline]
RIP: 0010:atomic_long_read include/linux/atomic/atomic-instrumented.h:3188 [inline]
RIP: 0010:__mutex_owner kernel/locking/mutex.h:47 [inline]
RIP: 0010:mutex_spin_on_owner+0x27b/0x360 kernel/locking/mutex.c:347
Code: be 08 00 00 00 e8 a5 e1 85 00 42 80 7c 35 00 00 74 08 4c 89 e7 e8 25 df 85 00 49 f7 04 24 01 00 00 00 0f 85 8c 00 00 00 f3 90 <4c> 89 e7 be 08 00 00 00 e8 78 e1 85 00 42 80 7c 35 00 00 0f 84 90
RSP: 0018:ffffc9001bb671a8 EFLAGS: 00000246
RAX: 1ffff1100b020000 RBX: ffffffff8f508ff0 RCX: ffffffff819cf498
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000001
RBP: 1ffffffff1ea11f4 R08: ffffffff8f508fa7 R09: 1ffffffff1ea11f4
R10: dffffc0000000000 R11: fffffbfff1ea11f5 R12: ffffffff8f508fa0
R13: ffffffff8f508ff0 R14: dffffc0000000000 R15: ffff888027ea0000
 mutex_optimistic_spin kernel/locking/mutex.c:464 [inline]
 __mutex_lock_common kernel/locking/mutex.c:602 [inline]
 __mutex_lock+0x311/0x1340 kernel/locking/mutex.c:760
 rtnl_lock net/core/rtnetlink.c:80 [inline]
 rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6814
 netlink_dump+0x6e4/0xe90 net/netlink/af_netlink.c:2327
 __netlink_dump_start+0x5cb/0x7e0 net/netlink/af_netlink.c:2442
 netlink_dump_start include/linux/netlink.h:341 [inline]
 rtnetlink_dump_start net/core/rtnetlink.c:6844 [inline]
 rtnetlink_rcv_msg+0x9eb/0xb70 net/core/rtnetlink.c:6911
 netlink_rcv_skb+0x205/0x470 net/netlink/af_netlink.c:2552
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x82c/0x9e0 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x219/0x270 net/socket.c:729
 sock_write_iter+0x258/0x330 net/socket.c:1179
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x54b/0xa90 fs/read_write.c:686
 ksys_write+0x145/0x250 fs/read_write.c:738
 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: 0033:0x7f0dff18e9a9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0dfff54038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f0dff3b5fa0 RCX: 00007f0dff18e9a9
RDX: 0000000000000024 RSI: 0000200000000000 RDI: 0000000000000005
RBP: 00007f0dff210d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f0dff3b5fa0 R15: 00007fff9ef15818
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g39773 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=15653
rcu: rcu_preempt kthread starved for 10502 jiffies! g39773 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:27128 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5351 [inline]
 __schedule+0x1737/0x4d30 kernel/sched/core.c:6954
 __schedule_loop kernel/sched/core.c:7036 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7051
 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/31 04:10 net d9104cec3e8f f8f2b4da .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in rtnl_dumpit
* Struck through repros no longer work on HEAD.