rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=621c/1/0x4000000000000000 softirq=23861/23863 fqs=1
rcu: (detected by 1, t=10505 jiffies, g=16165, q=1578 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6389 Comm: syz.1.18 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:__lock_acquire+0xab1/0x2df0 kernel/locking/lockdep.c:5234
Code: c9 85 c0 74 20 83 3d c1 92 98 0d 00 75 17 48 c7 c7 a4 f6 41 8d 48 c7 c6 62 55 32 8d e8 28 19 e6 ff 0f 0b 31 c9 48 83 79 40 00 <0f> 84 37 1c 00 00 48 09 dd 41 8b 45 20 89 c1 81 e1 00 80 04 00 81
RSP: 0018:ffffc90000007a38 EFLAGS: 00000086
RAX: 0000000000000000 RBX: 00000000857742d4 RCX: ffffffff92bb52d0
RDX: 000000009c99fba1 RSI: 000000006a212b4b RDI: ffff88802b460000
RBP: a26fb77000000000 R08: ffffffff9940db40 R09: ffffffff8482722d
R10: ffff88806e1cd340 R11: ffffed100dc39a6b R12: 0000000000000001
R13: ffff88802b460b48 R14: ffff88802b460000 R15: 0000000000000002
FS: 00007f5187ee46c0(0000) GS:ffff8881266f6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000564368f1c950 CR3: 000000002fc6c000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x120/0x350 kernel/locking/lockdep.c:5868
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
debug_object_deactivate+0x6d/0x360 lib/debugobjects.c:873
debug_hrtimer_deactivate kernel/time/hrtimer.c:450 [inline]
debug_deactivate+0x1d/0x1f0 kernel/time/hrtimer.c:490
__run_hrtimer kernel/time/hrtimer.c:1729 [inline]
__hrtimer_run_queues+0x2b0/0xc50 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+0x10b/0x400 arch/x86/kernel/apic/apic.c:1056
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lockdep_unregister_key+0x33a/0x3c0 kernel/locking/lockdep.c:6616
Code: 9f 00 00 00 89 c6 48 c7 c7 90 d7 1a 95 e8 0e 6a 6b 09 90 e9 2b fe ff ff e8 63 b7 68 09 41 f7 c6 00 02 00 00 74 9b fb 40 84 ed <75> 9a eb ab 0f 0b e9 01 ff ff ff 0f 0b e9 0b ff ff ff e8 af 81 dc
RSP: 0018:ffffc90003daf0a0 EFLAGS: 00000246
RAX: c3efd4abf8685c00 RBX: ffff88805577ca90 RCX: c3efd4abf8685c00
RDX: ffffffff92d652f8 RSI: ffffffff8d2664e0 RDI: ffffffff8b7dab00
RBP: ffff88802b460000 R08: ffffffff8db372a0 R09: ffffffff81a741f8
R10: dffffc0000000000 R11: fffffbfff1e6554f R12: 0000000000000000
R13: ffff88805577ca91 R14: 0000000000000246 R15: ffffffff93185328
__qdisc_destroy+0x166/0x400 net/sched/sch_generic.c:1083
taprio_attach+0x25a/0x380 net/sched/sch_taprio.c:2160
qdisc_graft+0x1228/0x1510 net/sched/sch_api.c:1162
__tc_modify_qdisc net/sched/sch_api.c:1756 [inline]
tc_modify_qdisc+0x1863/0x2080 net/sched/sch_api.c:1812
rtnetlink_rcv_msg+0x77c/0xb70 net/core/rtnetlink.c:6955
netlink_rcv_skb+0x1df/0x420 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+0x800/0xb20 net/netlink/af_netlink.c:1896
sock_sendmsg_nosec net/socket.c:714 [inline]
__sock_sendmsg+0x219/0x270 net/socket.c:729
____sys_sendmsg+0x4fd/0x7e0 net/socket.c:2614
___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668
__sys_sendmsg net/socket.c:2700 [inline]
__do_sys_sendmsg net/socket.c:2705 [inline]
__se_sys_sendmsg net/socket.c:2703 [inline]
__x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x8a/0x300 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f5186f8eba9
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:00007f5187ee4038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f51871d5fa0 RCX: 00007f5186f8eba9
RDX: 0000000000000000 RSI: 00002000000007c0 RDI: 0000000000000004
RBP: 00007f5187011e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f51871d6038 R14: 00007f51871d5fa0 R15: 00007ffe326742a8
rcu: rcu_preempt kthread starved for 10500 jiffies! g16165 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:27256 pid:15 tgid:15 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1742/0x4c30 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+0x301/0x1520 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
kthread+0x711/0x890 kernel/kthread.c:463
ret_from_fork+0x432/0x7c0 arch/x86/kernel/process.c:148
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: 6396 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:csd_lock_wait kernel/smp.c:351 [inline]
RIP: 0010:smp_call_function_many_cond+0xe1a/0x11d0 kernel/smp.c:877
Code: 45 8b 65 00 44 89 e6 83 e6 01 31 ff e8 ef 3c 0b 00 41 83 e4 01 49 bc 00 00 00 00 00 fc ff df 75 07 e8 9a 38 0b 00 eb 38 f3 90 <42> 0f b6 04 23 84 c0 75 11 41 f7 45 00 01 00 00 00 74 1e e8 7e 38
RSP: 0018:ffffc90003dbf5c0 EFLAGS: 00000293
RAX: ffffffff81b10472 RBX: 1ffff11017108339 RCX: ffff88802b461e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003dbf740 R08: ffffffff8f32aa77 R09: 1ffffffff1e6554e
R10: dffffc0000000000 R11: fffffbfff1e6554f R12: dffffc0000000000
R13: ffff8880b88419c8 R14: ffff8880b893b1c8 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881267f6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff29ef8058 CR3: 000000000d936000 CR4: 00000000003526f0
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1044
__flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
flush_tlb_mm_range+0x6a5/0x12a0 arch/x86/mm/tlb.c:1451
tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:490 [inline]
tlb_flush_mmu+0x1a7/0x680 mm/mmu_gather.c:403
tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497
free_ldt_pgtables+0x17b/0x320 arch/x86/kernel/ldt.c:411
arch_exit_mmap arch/x86/include/asm/mmu_context.h:234 [inline]
exit_mmap+0x179/0xb30 mm/mmap.c:1266
__mmput+0x118/0x420 kernel/fork.c:1129
exit_mm+0x1da/0x2c0 kernel/exit.c:582
do_exit+0x648/0x22f0 kernel/exit.c:949
do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
__do_sys_exit_group kernel/exit.c:1113 [inline]
__se_sys_exit_group kernel/exit.c:1111 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1111
x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x8a/0x300 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fa0336016c5
Code: Unable to access opcode bytes at 0x7fa03360169b.
RSP: 002b:00007fff29ef85c8 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007fff29ef8804 RCX: 00007fa0336016c5
RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000000
RBP: 0000000000000003 R08: 00007fff29ef86c0 R09: 0000000000000002
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007fff29ef8900 R14: 00007fa033811000 R15: 0000564360752d98