rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=43cc/1/0x4000000000000000 softirq=90234/90236 fqs=0
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5832/1:b..l
rcu: (detected by 1, t=10504 jiffies, g=97633, q=985 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 16887 Comm: syz.0.2412 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:lock_release+0x4/0x3c0 kernel/locking/lockdep.c:5876
Code: 00 e9 70 fe ff ff 41 be 2f 00 00 00 e9 0e ff ff ff 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <55> 41 57 41 56 41 55 41 54 53 48 83 ec 30 49 89 f5 49 89 fe 65 48
RSP: 0018:ffffc90000007d00 EFLAGS: 00000006
RAX: ffffffff89be669c RBX: ffffffff89be65d8 RCX: ffff888077b0dc40
RDX: 0000000000010000 RSI: ffffffff89be65d8 RDI: ffffffff8e95cce0
RBP: 0000000000000001 R08: ffff888052c3619f R09: 1ffff1100a586c33
R10: dffffc0000000000 R11: ffffed100a586c34 R12: ffff888052c36340
R13: ffff888052c36000 R14: 1bc16db3aec29ab0 R15: ffff888079892400
FS: 00007fc6ad1896c0(0000) GS:ffff88812521e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdaec7456b8 CR3: 000000005cb85000 CR4: 0000000000350ef0
Call Trace:
rcu_lock_release include/linux/rcupdate.h:310 [inline]
rcu_read_unlock include/linux/rcupdate.h:869 [inline]
advance_sched+0xb23/0xc90 net/sched/sch_taprio.c:993
__run_hrtimer kernel/time/hrtimer.c:1930 [inline]
__hrtimer_run_queues+0x3c0/0xa20 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+0x102/0x430 arch/x86/kernel/apic/apic.c:1067
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1061
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:_raw_spin_unlock_bh+0x4/0x40 kernel/locking/spinlock.c:213
Code: e9 7c 53 56 f5 cc e8 9b cd 79 f5 5b e9 70 53 56 f5 cc 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <41> 56 53 48 89 fb 48 83 c7 18 4c 8b 74 24 10 4c 89 f6 e8 95 fe e7
RSP: 0018:ffffc90004a36ef8 EFLAGS: 00000246
RAX: 1ffff92000946ee4 RBX: 1ffff92000946df8 RCX: 0000000000080000
RDX: ffffc90019d1a000 RSI: 0000000000000946 RDI: ffff888052c36158
RBP: ffffc90004a371d0 R08: ffffffff903353f7 R09: 1ffffffff2066a7e
R10: dffffc0000000000 R11: fffffbfff2066a7f R12: ffffc90004a37720
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff888052c362f8
spin_unlock_bh include/linux/spinlock.h:396 [inline]
taprio_change+0x3267/0x3e50 net/sched/sch_taprio.c:1999
taprio_init+0x96f/0xbe0 net/sched/sch_taprio.c:2124
qdisc_create+0x7c4/0xf20 net/sched/sch_api.c:1319
__tc_modify_qdisc net/sched/sch_api.c:1753 [inline]
tc_modify_qdisc+0x16f0/0x2290 net/sched/sch_api.c:1817
rtnetlink_rcv_msg+0x77e/0xbe0 net/core/rtnetlink.c:7003
netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:787 [inline]
__sock_sendmsg net/socket.c:802 [inline]
____sys_sendmsg+0x972/0x9f0 net/socket.c:2698
___sys_sendmsg+0x2a5/0x360 net/socket.c:2752
__sys_sendmsg net/socket.c:2784 [inline]
__do_sys_sendmsg net/socket.c:2789 [inline]
__se_sys_sendmsg net/socket.c:2787 [inline]
__x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2787
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc6ac39c819
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:00007fc6ad189028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fc6ac615fa0 RCX: 00007fc6ac39c819
RDX: 0000000000000010 RSI: 00002000000012c0 RDI: 0000000000000005
RBP: 00007fc6ac432c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc6ac616038 R14: 00007fc6ac615fa0 R15: 00007ffdfb749218
task:syz-executor state:R running task stack:21600 pid:5832 tgid:5832 ppid:5826 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x17b4/0x5680 kernel/sched/core.c:7188
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7369
preempt_schedule_thunk+0x16/0x30 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:1331 [inline]
copy_pmd_range+0x4f04/0x5970 mm/memory.c:1392
copy_pud_range mm/memory.c:1429 [inline]
copy_p4d_range mm/memory.c:1453 [inline]
copy_page_range+0xbe8/0x11f0 mm/memory.c:1539
dup_mmap+0xf40/0x1d90 mm/mmap.c:1840
dup_mm kernel/fork.c:1534 [inline]
copy_mm+0x13b/0x4a0 kernel/fork.c:1586
copy_process+0x1f1c/0x4450 kernel/fork.c:2262
kernel_clone+0x284/0x8f0 kernel/fork.c:2723
__do_sys_clone kernel/fork.c:2864 [inline]
__se_sys_clone kernel/fork.c:2848 [inline]
__x64_sys_clone+0x1b6/0x230 kernel/fork.c:2848
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdaeb9c5292
RSP: 002b:00007ffcba5db9e0 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffcba5db9e0 RCX: 00007fdaeb9c5292
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007ffcba5dbb6c R08: 0000000000000000 R09: 0000000000000001
R10: 00005555690be7d0 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000000927c0 R14: 00000000000ef5bf R15: 00007ffcba5dbbc0
rcu: rcu_preempt kthread starved for 10504 jiffies! g97633 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:27544 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5387 [inline]
__schedule+0x17b4/0x5680 kernel/sched/core.c:7188
__schedule_loop kernel/sched/core.c:7267 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7282
schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x312/0x11d0 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+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: 16880 Comm: dhcpcd-run-hook Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xfd4/0x13d0 kernel/smp.c:892
Code: 89 ee 83 e6 01 31 ff e8 fa fc 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 a5 f8 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 8a f8 0b 00 eb e5 44 89
RSP: 0018:ffffc90003467560 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffff8880b873c148 RCX: ffff8880354d9ec0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003467688 R08: ffffffff903353f7 R09: 1ffffffff2066a7e
R10: dffffc0000000000 R11: fffffbfff2066a7f R12: 1ffff110170c8589
R13: dffffc0000000000 R14: ffff8880b8642c48 R15: 0000000000000000
FS: 00007f0dcb5d4c80(0000) GS:ffff88812531e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0dcb8707b8 CR3: 000000007da64000 CR4: 0000000000350ef0
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+0x5c3/0x10b0 arch/x86/mm/tlb.c:1451
dup_mmap+0x17a2/0x1d90 mm/mmap.c:1905
dup_mm kernel/fork.c:1534 [inline]
copy_mm+0x13b/0x4a0 kernel/fork.c:1586
copy_process+0x1f1c/0x4450 kernel/fork.c:2262
kernel_clone+0x284/0x8f0 kernel/fork.c:2723
__do_sys_clone kernel/fork.c:2864 [inline]
__se_sys_clone kernel/fork.c:2848 [inline]
__x64_sys_clone+0x1b6/0x230 kernel/fork.c:2848
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0dcb76e636
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:00007ffd3ae1e840 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffd3ae1e848 RCX: 00007f0dcb76e636
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000562c2dde0c30 R08: 0000000000000000 R09: 0000000000000040
R10: 00007f0dcb5d4f50 R11: 0000000000000246 R12: 0000562c2ddeeb88
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000