rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (0 ticks this GP) idle=800c/1/0x4000000000000000 softirq=25947/25947 fqs=0
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P1168/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=25109, q=347 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6531 Comm: modprobe Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:trace_lock_acquire include/trace/events/lock.h:24 [inline]
RIP: 0010:lock_acquire+0x58/0x350 kernel/locking/lockdep.c:5831
Code: 8b 05 bc b1 1e 11 48 89 44 24 58 0f 1f 44 00 00 65 8b 05 bf b1 1e 11 83 f8 08 0f 83 83 01 00 00 89 c0 48 0f a3 05 68 47 20 0e <73> 0d e8 81 fb 08 00 84 c0 0f 84 c6 01 00 00 83 3d 32 78 20 0e 00
RSP: 0018:ffffc90000007c60 EFLAGS: 00000093
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888034ecc2c0
RBP: ffffffff899042a4 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff899041f0 R12: 0000000000000000
R13: ffff888034ecc2c0 R14: 0000000000000000 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125a33000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc1c4955440 CR3: 0000000078892000 CR4: 00000000003526f0
Call Trace:
__raw_spin_lock include/linux/spinlock_api_smp.h:158 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:158
spin_lock include/linux/spinlock.h:342 [inline]
advance_sched+0xb4/0xc20 net/sched/sch_taprio.c:930
__run_hrtimer kernel/time/hrtimer.c:1930 [inline]
__hrtimer_run_queues+0x3c0/0xa10 kernel/time/hrtimer.c:1994
hrtimer_interrupt+0x44b/0x950 kernel/time/hrtimer.c:2113
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
__sysvec_apic_timer_interrupt+0x102/0x420 arch/x86/kernel/apic/apic.c:1067
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:check_preemption_disabled+0x3/0xe0 lib/smp_processor_id.c:13
Code: e2 8b 48 c7 c6 00 7b e2 8b eb 1c 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 <41> 56 53 65 8b 05 f7 04 50 07 65 8b 0d ec 04 50 07 f7 c1 ff ff ff
RSP: 0018:ffffc900032ef020 EFLAGS: 00000282
RAX: 0000000000000001 RBX: ffffffff9061ee01 RCX: ffff88807f181ec0
RDX: ffffc900032ef101 RSI: ffffffff8be27b00 RDI: ffffffff8be27ac0
RBP: dffffc0000000000 R08: ffffc900032ef4c8 R09: 0000000000000000
R10: ffffc900032ef178 R11: fffff5200065de31 R12: ffffc900032ef4d8
R13: ffffc900032e8000 R14: ffffc900032ef128 R15: ffffffff8175c106
rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:752
rcu_read_unlock include/linux/rcupdate.h:867 [inline]
class_rcu_destructor include/linux/rcupdate.h:1181 [inline]
unwind_next_frame+0x1b76/0x2550 arch/x86/kernel/unwind_orc.c:709
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5296 [inline]
__kmalloc_noprof+0x35c/0x760 mm/slub.c:5308
kmalloc_noprof include/linux/slab.h:954 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]
tomoyo_encode2 security/tomoyo/realpath.c:45 [inline]
tomoyo_encode+0x28b/0x550 security/tomoyo/realpath.c:80
tomoyo_realpath_from_path+0x58d/0x5d0 security/tomoyo/realpath.c:283
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_check_open_permission+0x229/0x470 security/tomoyo/file.c:776
security_file_open+0xa9/0x240 security/security.c:2739
do_dentry_open+0x384/0x14e0 fs/open.c:924
vfs_open+0x3b/0x340 fs/open.c:1079
do_open fs/namei.c:4699 [inline]
path_openat+0x2e06/0x3850 fs/namei.c:4858
do_file_open+0x23e/0x4a0 fs/namei.c:4887
do_sys_openat2+0x113/0x200 fs/open.c:1364
do_sys_open fs/open.c:1370 [inline]
__do_sys_openat fs/open.c:1386 [inline]
__se_sys_openat fs/open.c:1381 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1381
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x10a/0x4d0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fc1c4c370ba
Code: 41 89 f2 48 89 54 24 e0 41 83 e2 40 75 2a 89 f0 f7 d0 a9 00 00 41 00 74 1f 89 f2 b8 01 01 00 00 48 89 fe bf 9c ff ff ff 0f 05 <48> 3d 00 f0 ff ff 77 2e c3 0f 1f 44 00 00 48 8d 44 24 08 c7 44 24
RSP: 002b:00007ffd4f7af2b8 EFLAGS: 00000206 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007ffd4f7af330 RCX: 00007fc1c4c370ba
RDX: 0000000000080000 RSI: 00007ffd4f7af330 RDI: 00000000ffffff9c
RBP: 00007ffd4f7af320 R08: 00007ffd4f7af527 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000016
R13: 00007fc1c4c0b000 R14: 00007ffd4f7af540 R15: 0000000000000000
task:kworker/u8:9 state:R running task stack:22816 pid:1168 tgid:1168 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: events_unbound linkwatch_event
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1821/0x5650 kernel/sched/core.c:7189
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7513
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
irqentry_exit+0x14a/0x750 kernel/entry/common.c:164
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:memcpy_orig+0x6c/0x130 arch/x86/lib/memcpy_64.S:101
Code: 44 48 01 d6 48 01 d7 48 83 ea 20 0f 1f 00 48 83 ea 20 4c 8b 46 f8 4c 8b 4e f0 4c 8b 56 e8 4c 8b 5e e0 48 8d 76 e0 4c 89 47 f8 <4c> 89 4f f0 4c 89 57 e8 4c 89 5f e0 48 8d 7f e0 73 d2 83 c2 20 48
RSP: 0018:ffffc90005517138 EFLAGS: 00000202
RAX: ffff88807c3a440c RBX: 0000000000000000 RCX: ffffffff8a28b615
RDX: 0000000000000070 RSI: ffffc90005517230 RDI: ffff88807c3a44bc
RBP: ffffc90005517370 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000120
R13: 0000000000000000 R14: ffff88807c3a440c R15: ffffc900055171a0
__snmp6_fill_stats64 net/ipv6/addrconf.c:5789 [inline]
snmp6_fill_stats+0x6d5/0x980 net/ipv6/addrconf.c:5798
inet6_fill_ifla6_stats_attrs net/ipv6/addrconf.c:5815 [inline]
inet6_fill_ifla6_attrs+0x1081/0x25e0 net/ipv6/addrconf.c:5851
inet6_fill_link_af+0x9b/0x120 net/ipv6/addrconf.c:5893
rtnl_fill_link_af+0x1c8/0x440 net/core/rtnetlink.c:1919
rtnl_fill_ifinfo+0x1e06/0x20f0 net/core/rtnetlink.c:2190
rtmsg_ifinfo_build_skb+0x17d/0x260 net/core/rtnetlink.c:4454
rtmsg_ifinfo_event net/core/rtnetlink.c:4487 [inline]
rtmsg_ifinfo+0x8c/0x1a0 net/core/rtnetlink.c:4496
netif_state_change+0x297/0x3a0 net/core/dev.c:1605
__linkwatch_run_queue+0x572/0x840 net/core/link_watch.c:240
linkwatch_event+0x4c/0x60 net/core/link_watch.c:314
process_one_work kernel/workqueue.c:3314 [inline]
process_scheduled_works+0xb5d/0x1850 kernel/workqueue.c:3397
worker_thread+0xa59/0xfc0 kernel/workqueue.c:3478
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x510/0xb60 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: rcu_preempt kthread starved for 10502 jiffies! g25109 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:27880 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1821/0x5650 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7283
schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x312/0x11c0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x510/0xb60 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 6509 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xfcb/0x13b0 kernel/smp.c:892
Code: 79 45 8b 2e 44 89 ee 83 e6 01 31 ff e8 1e d8 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 c9 d3 0b 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 06 01 00 00 00 74 1e e8 ae d3 0b
RSP: 0018:ffffc9000379f560 EFLAGS: 00000293
RAX: ffffffff81b78b02 RBX: ffff8880b873c148 RCX: ffff888028e59ec0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000379f688 R08: ffffffff8fc065f7 R09: 1ffffffff1f80cbe
R10: dffffc0000000000 R11: fffffbfff1f80cbf R12: 1ffff110170c8585
R13: dffffc0000000000 R14: ffff8880b8642c28 R15: 0000000000000000
FS: 00007fde28830c80(0000) GS:ffff888125b33000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fde28acc7b8 CR3: 0000000074f58000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1057
__flush_tlb_multi arch/x86/include/asm/paravirt.h:46 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
flush_tlb_mm_range+0x5b7/0x1090 arch/x86/mm/tlb.c:1451
dup_mmap+0x17a6/0x1d90 mm/mmap.c:1905
dup_mm kernel/fork.c:1534 [inline]
copy_mm+0x13b/0x4a0 kernel/fork.c:1586
copy_process+0x1f18/0x4440 kernel/fork.c:2264
kernel_clone+0x2d7/0x940 kernel/fork.c:2722
__do_sys_clone kernel/fork.c:2863 [inline]
__se_sys_clone kernel/fork.c:2847 [inline]
__x64_sys_clone+0x1b6/0x230 kernel/fork.c:2847
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x10a/0x4d0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fde289ca636
Code: 89 df e8 6d e8 f6 ff 45 31 c0 31 d2 31 f6 64 48 8b 04 25 10 00 00 00 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 52 89 c5 85 c0 75 31 64 48 8b 04 25 10 00 00
RSP: 002b:00007ffdb4da0050 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffdb4da0058 RCX: 00007fde289ca636
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 000055daac73fc30 R08: 0000000000000000 R09: 0000000000000030
R10: 00007fde28830f50 R11: 0000000000000246 R12: 000055daac74d290
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000