rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (3 ticks this GP) idle=1d44/1/0x4000000000000000 softirq=18865/18865 fqs=0
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6050/1:b..l
rcu: (detected by 1, t=10725 jiffies, g=13001, q=1230 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5503 Comm: dhcpcd Not tainted 6.16.0-syzkaller-06600-g1dbf1d590d10 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x55/0xb0 kernel/rcu/tree.c:745
Code: ec b9 8d 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 4c 73 7c 00 48 c7 c3 58 2f 9b 92 49 03 1e 48 89 d8 48 c1 e8 03 <42> 0f b6 04 38 84 c0 75 34 8b 03 65 ff 0d b9 9f f3 10 74 11 83 e0
RSP: 0000:ffffc90000007bb0 EFLAGS: 00000806
RAX: 1ffff110170c65eb RBX: ffff8880b8632f58 RCX: 833817ec53c11c00
RDX: 0000000000000000 RSI: ffffffff8be309e0 RDI: ffffffff8be309a0
RBP: ffffffff89910ec8 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed100efbe85e R12: 0000000000000002
R13: ffffffff8e13c4e0 R14: ffffffff8db9ecd0 R15: dffffc0000000000
FS: 00007f386b473740(0000) GS:ffff888125c80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc04dc8fdc CR3: 000000007c840000 CR4: 00000000003526f0
Call Trace:
trace_lock_acquire include/trace/events/lock.h:24 [inline]
lock_acquire+0x5f/0x360 kernel/locking/lockdep.c:5831
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
advance_sched+0xa14/0xc90 net/sched/sch_taprio.c:990
__run_hrtimer kernel/time/hrtimer.c:1761 [inline]
__hrtimer_run_queues+0x52c/0xc60 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+0x108/0x410 arch/x86/kernel/apic/apic.c:1056
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xd33/0x12d0 kernel/smp.c:877
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 06 70 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 b1 6b 0b 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 95 6b
RSP: 0000:ffffc90003acf700 EFLAGS: 00000293
RAX: ffffffff81b4451b RBX: 1ffff110170e7f59 RCX: ffff88802f2f9e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003acf880 R08: ffffffff8fa07bf7 R09: 1ffffffff1f40f7e
R10: dffffc0000000000 R11: fffffbfff1f40f7f R12: ffff8880b873fac8
R13: dffffc0000000000 R14: ffff8880b863b180 R15: 0000000000000001
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+0x6b1/0x12c0 arch/x86/mm/tlb.c:1451
flush_tlb_page arch/x86/include/asm/tlbflush.h:324 [inline]
ptep_clear_flush+0x120/0x170 mm/pgtable-generic.c:101
wp_page_copy mm/memory.c:3653 [inline]
do_wp_page+0x1bc2/0x5800 mm/memory.c:4048
handle_pte_fault mm/memory.c:6103 [inline]
__handle_mm_fault+0x1144/0x5620 mm/memory.c:6230
handle_mm_fault+0x40a/0x8e0 mm/memory.c:6399
do_user_addr_fault+0xa81/0x1390 arch/x86/mm/fault.c:1336
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x5644b829f87b
Code: 89 e1 48 89 ea 48 8d 3d c3 b7 04 00 e8 1e fd ff ff 8b 15 b8 d7 04 00 80 e6 08 0f 84 6f ff ff ff 4c 89 e1 48 89 ea 31 f6 89 df <89> 44 24 0c e8 cc 7b ff ff 8b 44 24 0c e9 53 ff ff ff 0f 1f 00 89
RSP: 002b:00007ffc04dc8fd0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000007 RCX: 00007ffc04dc9410
RDX: 00005644b82d62b7 RSI: 0000000000000000 RDI: 0000000000000007
RBP: 00005644b82d62b7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffc04dc9410
R13: 00005644c279ddf0 R14: 0000000000000001 R15: 00007ffc04dc99b0
task:kworker/0:4 state:R running task stack:25992 pid:6050 tgid:6050 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: events_power_efficient gc_worker
Call Trace:
context_switch kernel/sched/core.c:5351 [inline]
__schedule+0x1737/0x4d30 kernel/sched/core.c:6954
preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7281
irqentry_exit+0x6f/0x90 kernel/entry/common.c:196
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:seqcount_lockdep_reader_access+0x17e/0x1c0 include/linux/seqlock.h:75
Code: f8 4d 85 e4 75 16 e8 a1 62 1d f8 eb 15 e8 9a 62 1d f8 e8 05 7b cd 01 4d 85 e4 74 ea e8 8b 62 1d f8 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3e 00 00 00 00 66 43 c7 44 3e 09 00 00 43 c6 44 3e 0b 00
RSP: 0018:ffffc90003bdf860 EFLAGS: 00000293
RAX: ffffffff89a24e25 RBX: 0000000000000000 RCX: ffff88807b605a00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90003bdf910 R08: ffffffff8fa07bf7 R09: 1ffffffff1f40f7e
R10: dffffc0000000000 R11: fffffbfff1f40f7f R12: 0000000000000200
R13: ffff888074249818 R14: 1ffff9200077bf0c R15: dffffc0000000000
nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:342 [inline]
gc_worker+0x308/0x1380 net/netfilter/nf_conntrack_core.c:1548
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: rcu_preempt kthread starved for 10725 jiffies! g13001 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:26760 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5351 [inline]
__schedule+0x1737/0x4d30 kernel/sched/core.c:6954
__schedule_loop kernel/sched/core.c:7036 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7051
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 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: 5976 Comm: syz-executor Not tainted 6.16.0-syzkaller-06600-g1dbf1d590d10 #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:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xd33/0x12d0 kernel/smp.c:877
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 06 70 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 b1 6b 0b 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 95 6b
RSP: 0000:ffffc90004407700 EFLAGS: 00000293
RAX: ffffffff81b4451b RBX: 1ffff110170c8385 RCX: ffff888026de9e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90004407880 R08: ffffffff8fa07bf7 R09: 1ffffffff1f40f7e
R10: dffffc0000000000 R11: fffffbfff1f40f7f R12: ffff8880b8641c28
R13: dffffc0000000000 R14: ffff8880b873b180 R15: 0000000000000000
FS: 0000555581667500(0000) GS:ffff888125d80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffcb10b7058 CR3: 00000000733da000 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+0x6b1/0x12c0 arch/x86/mm/tlb.c:1451
flush_tlb_page arch/x86/include/asm/tlbflush.h:324 [inline]
ptep_clear_flush+0x120/0x170 mm/pgtable-generic.c:101
wp_page_copy mm/memory.c:3653 [inline]
do_wp_page+0x1bc2/0x5800 mm/memory.c:4048
handle_pte_fault mm/memory.c:6103 [inline]
__handle_mm_fault+0x1144/0x5620 mm/memory.c:6230
handle_mm_fault+0x40a/0x8e0 mm/memory.c:6399
do_user_addr_fault+0xa81/0x1390 arch/x86/mm/fault.c:1336
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7fac61d85256
Code: fd ff ff 90 e8 7b 01 00 00 41 89 c4 85 c0 0f 84 82 fd ff ff 49 c7 c5 a8 ff ff ff 48 83 3d 79 ba 1f 00 00 64 45 8b 75 00 74 05 c5 84 fc ff e8 d0 f5 fb ff e9 d9 fc ff ff 0f 1f 00 48 8d 7e 58
RSP: 002b:00007ffcb10b7060 EFLAGS: 00010202
RAX: 0000000000000006 RBX: 0000000000000000 RCX: 00007fac61d853d3
RDX: 0000000000000006 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 00005555816677d0 R11: 0000000000000246 R12: 0000000000000006
R13: ffffffffffffffa8 R14: 0000000000000006 R15: 00007ffcb10b71f0