syzbot


INFO: rcu detected stall in inet_rtm_newaddr (2)

Status: upstream: reported C repro on 2025/05/06 14:06
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+51cd74c5dfeafd65e488@syzkaller.appspotmail.com
First crash: 184d, last: 1d08h
Cause bisection: failed (error log, bisect log)
  
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [net?] INFO: rcu detected stall in inet_rtm_newaddr (2) 9 (11) 2025/10/24 00:11
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in inet_rtm_newaddr bpf net 1 4 396d 521d 0/29 auto-obsoleted due to no activity on 2025/01/03 16:01
Last patch testing requests (5)
Created Duration User Patch Repo Result
2025/10/25 12:04 20m retest repro upstream report log
2025/10/25 10:42 22m retest repro net-next report log
2025/10/25 10:42 33m retest repro net-next report log
2025/08/16 09:30 43m retest repro upstream report log
2025/05/20 10:11 41m retest repro upstream report log
Fix bisection attempts (1)
Created Duration User Patch Repo Result
2025/06/07 06:06 2h45m bisect fix upstream OK (0) job log log

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=83dc/1/0x4000000000000000 softirq=15551/15553 fqs=1
rcu: 	(detected by 0, t=10502 jiffies, g=11393, q=295 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5951 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:kasan_check_range+0xb/0x2c0 mm/kasan/generic.c:199
Code: b8 ea ff ff ff eb e1 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 55 41 57 41 56 41 55 <41> 54 53 b0 01 48 85 f6 0f 84 ba 01 00 00 4c 8d 04 37 49 39 f8 0f
RSP: 0018:ffffc90000a08c00 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff8880757e92e8 RCX: ffffffff819dfacd
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880757e92e8
RBP: ffff888031ca7950 R08: ffff888031ca7887 R09: 1ffff11006394f10
R10: dffffc0000000000 R11: ffffed1006394f11 R12: dffffc0000000000
R13: ffff8880757e9000 R14: ffff8880757e92ec R15: ffff888031ca7400
FS:  00005555652af500(0000) GS:ffff88812623c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000500 CR3: 0000000030c1e000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 instrument_atomic_read include/linux/instrumented.h:68 [inline]
 atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline]
 queued_spin_is_locked include/asm-generic/qspinlock.h:57 [inline]
 debug_spin_unlock kernel/locking/spinlock_debug.c:101 [inline]
 do_raw_spin_unlock+0x4d/0x240 kernel/locking/spinlock_debug.c:141
 __raw_spin_unlock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_unlock+0x1e/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 advance_sched+0x99f/0xc90 net/sched/sch_taprio.c:986
 __run_hrtimer kernel/time/hrtimer.c:1777 [inline]
 __hrtimer_run_queues+0x52c/0xc60 kernel/time/hrtimer.c:1841
 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1903
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline]
 __sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1058
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1052
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:queue_delayed_work_on+0x201/0x280 kernel/workqueue.c:2566
Code: 4d 85 e4 75 16 e8 2f 0c 36 00 eb 15 e8 28 0c 36 00 e8 c3 49 bc 09 4d 85 e4 74 ea e8 19 0c 36 00 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 04 2f 00 00 00 00 66 43 c7 44 2f 09 00 00 43 c6 44 2f 0b 00
RSP: 0018:ffffc90004f1f420 EFLAGS: 00000293
RAX: ffffffff8189f857 RBX: ffff88807cd1ae01 RCX: ffff888029613c80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90004f1f510 R08: ffffffff8f7cdc77 R09: 1ffffffff1ef9b8e
R10: dffffc0000000000 R11: fffffbfff1ef9b8f R12: 0000000000000200
R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff920009e3e8c
 queue_delayed_work include/linux/workqueue.h:684 [inline]
 __inet_insert_ifa+0x9e6/0xbf0 net/ipv4/devinet.c:560
 inet_rtm_newaddr+0xf3a/0x18b0 net/ipv4/devinet.c:1001
 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6951
 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:742
 __sys_sendto+0x3bd/0x520 net/socket.c:2244
 __do_sys_sendto net/socket.c:2251 [inline]
 __se_sys_sendto net/socket.c:2247 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2247
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6a0039155c
Code: 2a 5f 02 00 44 8b 4c 24 2c 4c 8b 44 24 20 89 c5 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 34 89 ef 48 89 44 24 08 e8 70 5f 02 00 48 8b
RSP: 002b:00007ffe06e21570 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f6a01114620 RCX: 00007f6a0039155c
RDX: 0000000000000028 RSI: 00007f6a01114670 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffe06e215c4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f6a01114670 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10499 jiffies! g11393 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=5906
rcu: rcu_preempt kthread starved for 10500 jiffies! g11393 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
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:27912 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7026
 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+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/05 04:02 net e120f46768d9 a6c9c731 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: rcu detected stall in inet_rtm_newaddr
2025/10/11 07:41 net-next 18a7e218cfcd ff1712fe .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: rcu detected stall in inet_rtm_newaddr
2025/05/06 09:17 upstream 01f95500a162 ae98e6b9 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in inet_rtm_newaddr
2025/10/10 07:36 net-next 07fdad3a9375 ff1712fe .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce INFO: rcu detected stall in inet_rtm_newaddr
2025/07/10 06:48 upstream 8c2e52ebbe88 956bd956 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in inet_rtm_newaddr
* Struck through repros no longer work on HEAD.