rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=a51c/1/0x4000000000000000 softirq=164063/164064 fqs=0
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P29425/3:b..l P28294/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=177861, q=867 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 27903 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:rcu_lock_release include/linux/rcupdate.h:310 [inline]
RIP: 0010:rcu_read_unlock include/linux/rcupdate.h:871 [inline]
RIP: 0010:advance_sched+0xb0b/0xc80 net/sched/sch_taprio.c:994
Code: 3b af 0a f8 c6 05 60 03 60 06 01 48 c7 c7 c0 a2 e3 8c be 66 03 00 00 48 c7 c2 60 a3 e3 8c e8 2c a9 e6 f7 48 c7 c7 a0 9b 95 8e <48> 89 de e8 ad 8f e6 f7 e8 d8 3d f0 f7 b8 01 00 00 00 48 81 c4 90
RSP: 0018:ffffc90000007d10 EFLAGS: 00000006
RAX: ffffffff89bb71d3 RBX: ffffffff89bb7108 RCX: ffff88804dd31f00
RDX: 0000000000010000 RSI: 0000000000000000 RDI: ffffffff8e959ba0
RBP: 0000000000000000 R08: ffff88807d2d919f R09: 1ffff1100fa5b233
R10: dffffc0000000000 R11: ffffed100fa5b234 R12: ffff88805ac83400
R13: ffff88807d2d9000 R14: dffffc0000000000 R15: ffff88807d2d9340
FS: 000055558821c500(0000) GS:ffff88812525d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f46985e8158 CR3: 000000005e9f1000 CR4: 0000000000350ef0
Call Trace:
__run_hrtimer kernel/time/hrtimer.c:2032 [inline]
__hrtimer_run_queues+0x3bc/0xa10 kernel/time/hrtimer.c:2096
hrtimer_interrupt+0x448/0x910 kernel/time/hrtimer.c:2215
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
__sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:lock_release+0x0/0x3c0 kernel/locking/lockdep.c:5876
Code: bf 00 00 50 00 e9 4f fe ff ff 41 bf 2f 00 00 00 e9 06 ff ff ff 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 55 41 57 41 56 41 55 41 54 53 48 83 ec 30 49 89 f5 49
RSP: 0018:ffffc9000524f4d8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffc9000524f598 RCX: ffffc9000524f940
RDX: ffffc9000524f501 RSI: ffffffff8176a21f RDI: ffffffff8e959ba0
RBP: 1ffffffff21a9001 R08: ffffc9000524f928 R09: ffffc9000524f5d8
R10: dffffc0000000000 R11: fffff52000a49ebd R12: ffffc90005248000
R13: ffffffff8176a21f R14: ffffc9000524f588 R15: ffffc9000524f938
rcu_lock_release include/linux/rcupdate.h:310 [inline]
rcu_read_unlock include/linux/rcupdate.h:871 [inline]
class_rcu_destructor include/linux/rcupdate.h:1183 [inline]
unwind_next_frame+0x1baa/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
kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2700 [inline]
slab_free mm/slub.c:6310 [inline]
kfree+0x1c5/0x640 mm/slub.c:6625
xt_free_table_info+0xfe/0x180 net/netfilter/x_tables.c:1302
__do_replace+0x8d9/0xac0 net/ipv4/netfilter/arp_tables.c:943
do_replace net/ipv4/netfilter/arp_tables.c:999 [inline]
do_arpt_set_ctl+0xb99/0x10b0 net/ipv4/netfilter/arp_tables.c:1440
nf_setsockopt+0x26f/0x290 net/netfilter/nf_sockopt.c:101
do_sock_setsockopt+0x17c/0x1b0 net/socket.c:2368
__sys_setsockopt net/socket.c:2393 [inline]
__do_sys_setsockopt net/socket.c:2399 [inline]
__se_sys_setsockopt net/socket.c:2396 [inline]
__x64_sys_setsockopt+0x13d/0x1b0 net/socket.c:2396
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f469839e69a
Code: 48 83 ec 10 48 63 c9 48 63 ff 45 89 c9 6a 2c e8 6c 99 fb ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 49 89 ca b8 36 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 06 c3 0f 1f 44 00 00 48 c7 c2 e8 ff ff ff f7
RSP: 002b:00007fff42de79d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f469839e69a
RDX: 0000000000000060 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007fff42de7a40 R08: 0000000000000408 R09: 0000000000000000
R10: 00007f46985e87b0 R11: 0000000000000246 R12: 00007fff42de79ec
R13: 00007f46984338bd R14: 00000000001642ec R15: 00007fff42de8130
task:syz-executor state:R running task stack:22392 pid:28294 tgid:28294 ppid:28276 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5504 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7228
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7409
preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:169 [inline]
_raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:190
spin_unlock include/linux/spinlock.h:390 [inline]
copy_pte_range mm/memory.c:1347 [inline]
copy_pmd_range+0x4e08/0x5880 mm/memory.c:1408
copy_pud_range mm/memory.c:1445 [inline]
copy_p4d_range mm/memory.c:1469 [inline]
copy_page_range+0xc26/0x1250 mm/memory.c:1555
dup_mmap+0xf21/0x1d90 mm/mmap.c:1840
dup_mm kernel/fork.c:1537 [inline]
copy_mm+0x11a/0x480 kernel/fork.c:1589
copy_process+0x1e4a/0x42e0 kernel/fork.c:2287
kernel_clone+0x2d7/0x940 kernel/fork.c:2745
__do_sys_clone kernel/fork.c:2886 [inline]
__se_sys_clone kernel/fork.c:2870 [inline]
__x64_sys_clone+0x1b6/0x230 kernel/fork.c:2870
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbf2b3c58d2
RSP: 002b:00007ffd718b4c60 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffd718b4c60 RCX: 00007fbf2b3c58d2
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007ffd718b4dec R08: 0000000000000000 R09: 0000000000000001
R10: 00005555620b47d0 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000000927c0 R14: 0000000000164417 R15: 00007ffd718b4e40
task:dhcpcd-run-hook state:R running task stack:28288 pid:29425 tgid:29425 ppid:29421 task_flags:0x400040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5504 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7228
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7409
preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:169 [inline]
_raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:190
spin_unlock include/linux/spinlock.h:390 [inline]
filemap_map_pages+0x1911/0x2050 mm/filemap.c:3953
do_fault_around mm/memory.c:5867 [inline]
do_read_fault mm/memory.c:5900 [inline]
do_fault mm/memory.c:6043 [inline]
do_pte_missing+0x2115/0x3540 mm/memory.c:4566
handle_pte_fault mm/memory.c:6427 [inline]
__handle_mm_fault mm/memory.c:6565 [inline]
handle_mm_fault+0x1b36/0x3080 mm/memory.c:6734
do_user_addr_fault+0xa4d/0x1340 arch/x86/mm/fault.c:1343
handle_page_fault arch/x86/mm/fault.c:1483 [inline]
exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
RIP: 0033:0x7f5e7df80ee0
RSP: 002b:00007fff3990f818 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 0000564992e13760 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000564992e18bd0
RBP: 0000564992e194c0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000564992e11910
R13: 0000564992e11c30 R14: 0000000000000000 R15: 00007f5e7e188460
rcu: rcu_preempt kthread starved for 10502 jiffies! g177861 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:28056 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5504 [inline]
__schedule+0x17d9/0x56c0 kernel/sched/core.c:7228
__schedule_loop kernel/sched/core.c:7307 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7322
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2123
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2325
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 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: 29426 Comm: syz.1.7669 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0x10b5/0x14b0 kernel/smp.c:892
Code: 1e 89 de 83 e6 01 31 ff e8 28 1d 0c 00 83 e3 01 48 bb 00 00 00 00 00 fc ff df 75 07 e8 d4 18 0c 00 eb 37 f3 90 41 0f b6 04 1c <84> c0 75 10 41 f7 06 01 00 00 00 74 1e e8 b9 18 0c 00 eb e5 44 89
RSP: 0018:ffffc90003e8f980 EFLAGS: 00000246
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000080000
RDX: ffffc90003f51000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc90003e8fab0 R08: ffffffff903188f7 R09: 1ffffffff206311e
R10: dffffc0000000000 R11: ffffffff81741150 R12: 1ffff110170c85c5
R13: ffff8880b873c2c8 R14: ffff8880b8642e28 R15: 0000000000000000
FS: 00007ff720b196c0(0000) GS:ffff88812535d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff71fc4f270 CR3: 00000000912a5000 CR4: 0000000000350ef0
Call Trace:
clock_was_set+0x715/0x7e0 kernel/time/hrtimer.c:999
do_adjtimex+0x25d/0x370 kernel/time/timekeeping.c:3005
do_clock_adjtime kernel/time/posix-timers.c:1169 [inline]
__do_sys_clock_adjtime kernel/time/posix-timers.c:1181 [inline]
__se_sys_clock_adjtime kernel/time/posix-timers.c:1172 [inline]
__x64_sys_clock_adjtime+0x252/0x340 kernel/time/posix-timers.c:1172
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff71fb9ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff720b19028 EFLAGS: 00000246 ORIG_RAX: 0000000000000131
RAX: ffffffffffffffda RBX: 00007ff71fe15fa0 RCX: 00007ff71fb9ce59
RDX: 0000000000000000 RSI: 0000200000001100 RDI: 0000000000000000
RBP: 00007ff71fc32e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff71fe16038 R14: 00007ff71fe15fa0 R15: 00007fffc7c39488