rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (1 GPs behind) idle=680c/1/0x4000000000000000 softirq=18072/18073 fqs=0
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5992/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=12801, q=3694 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6111 Comm: kworker/1:7 Not tainted 6.16.0-syzkaller-12256-g561c80369df0 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: events_power_efficient gc_worker
RIP: 0010:rb_erase_cached include/linux/rbtree.h:123 [inline]
RIP: 0010:timerqueue_del+0x66/0x100 lib/timerqueue.c:57
Code: 3e 4c 89 ff 4c 89 f6 e8 e8 65 4a f6 4d 39 f7 0f 84 9d 00 00 00 e8 7a 63 4a f6 4c 8d 63 08 4d 89 e7 49 c1 ef 03 43 80 3c 2f 00 <74> 08 4c 89 e7 e8 90 d0 ad f6 4d 39 34 24 74 07 e8 55 63 4a f6 eb
RSP: 0018:ffffc90000a08d08 EFLAGS: 00000046
RAX: ffffffff8b754836 RBX: ffff8880b8727bd0 RCX: ffff88802674bc00
RDX: 0000000000010000 RSI: ffff888079e5d340 RDI: 0000000000000001
RBP: 1ffff1100f3cba68 R08: ffffffff8fa37e37 R09: 1ffffffff1f46fc6
R10: dffffc0000000000 R11: fffffbfff1f46fc7 R12: ffff8880b8727bd8
R13: dffffc0000000000 R14: ffff888079e5d340 R15: 1ffff110170e4f7b
FS: 0000000000000000(0000) GS:ffff888125d1c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc6b83977e8 CR3: 000000007791c000 CR4: 00000000003526f0
Call Trace:
__remove_hrtimer kernel/time/hrtimer.c:1121 [inline]
__run_hrtimer kernel/time/hrtimer.c:1741 [inline]
__hrtimer_run_queues+0x364/0xc60 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: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+0x5a/0xb0 kernel/rcu/tree.c:751
Code: f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 1c bb 7c 00 48 c7 c3 98 6f a1 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 49 e2 f9 10 74 11 83 e0 04 c1 e8 02 5b
RSP: 0018:ffffc90002e67898 EFLAGS: 00000a06
RAX: 0000000000000000 RBX: ffff8880b8732f98 RCX: 87c75711a99c0500
RDX: 0000000000000000 RSI: ffffffff8be333e0 RDI: ffffffff8be333a0
RBP: ffffc90002e67a70 R08: ffffffff8fa37e37 R09: 1ffffffff1f46fc6
R10: dffffc0000000000 R11: fffffbfff1f46fc7 R12: ffff8880b8739700
R13: ffffffff89ac4ab4 R14: ffffffff8dbded18 R15: dffffc0000000000
trace_lock_release include/trace/events/lock.h:69 [inline]
lock_release+0x4b/0x3e0 kernel/locking/lockdep.c:5879
rcu_lock_release include/linux/rcupdate.h:341 [inline]
rcu_read_unlock include/linux/rcupdate.h:871 [inline]
gc_worker+0xba6/0x1380 net/netfilter/nf_conntrack_core.c:1617
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3319
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
task:syz-executor state:R running task stack:21832 pid:5992 tgid:5992 ppid:5977 task_flags:0x400140 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7145
preempt_schedule+0xae/0xc0 kernel/sched/core.c:7169
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__local_bh_enable_ip+0x13e/0x1c0 kernel/softirq.c:414
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:910 [inline]
__dev_queue_xmit+0x1d79/0x3b50 net/core/dev.c:4740
dev_queue_xmit include/linux/netdevice.h:3358 [inline]
__netlink_deliver_tap_skb net/netlink/af_netlink.c:307 [inline]
__netlink_deliver_tap+0x5ad/0x850 net/netlink/af_netlink.c:325
netlink_deliver_tap+0x19c/0x1b0 net/netlink/af_netlink.c:338
__netlink_sendskb net/netlink/af_netlink.c:1262 [inline]
netlink_sendskb+0x68/0x140 net/netlink/af_netlink.c:1271
netlink_unicast+0x397/0x9e0 net/netlink/af_netlink.c:1361
netlink_rcv_skb+0x28c/0x470 net/netlink/af_netlink.c:2558
netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1346
netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
sock_sendmsg_nosec net/socket.c:714 [inline]
__sock_sendmsg+0x21c/0x270 net/socket.c:729
__sys_sendto+0x3bd/0x520 net/socket.c:2228
__do_sys_sendto net/socket.c:2235 [inline]
__se_sys_sendto net/socket.c:2231 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2231
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbfd4f90a7c
RSP: 002b:00007fbfd52df670 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fbfd5ce4620 RCX: 00007fbfd4f90a7c
RDX: 0000000000000040 RSI: 00007fbfd5ce4670 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007fbfd52df6c4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fbfd5ce4670 R15: 0000000000000000
rcu: rcu_preempt kthread starved for 10502 jiffies! g12801 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
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:26792 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 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+0x301/0x1540 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285
kthread+0x70e/0x8a0 kernel/kthread.c:463
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: 0 UID: 0 PID: 5974 Comm: syz-executor Not tainted 6.16.0-syzkaller-12256-g561c80369df0 #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 b6 62 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 61 5e 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 45 5e
RSP: 0000:ffffc900041cf340 EFLAGS: 00000293
RAX: ffffffff81b44d6b RBX: 1ffff110170e7f61 RCX: ffff88802e728000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900041cf4c0 R08: ffffffff8fa37e37 R09: 1ffffffff1f46fc6
R10: dffffc0000000000 R11: fffffbfff1f46fc7 R12: ffff8880b873fb08
R13: dffffc0000000000 R14: ffff8880b863b1c0 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125c1c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32263fff CR3: 000000000df36000 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+0x6b1/0x12d0 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+0x17c/0xb50 mm/mmap.c:1266
__mmput+0x118/0x430 kernel/fork.c:1129
exit_mm+0x1da/0x2c0 kernel/exit.c:582
do_exit+0x648/0x2300 kernel/exit.c:949
do_group_exit+0x21c/0x2d0 kernel/exit.c:1102
get_signal+0x1286/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd139f84e57
Code: Unable to access opcode bytes at 0x7fd139f84e2d.
RSP: 002b:00007ffc38914c10 EFLAGS: 00000293 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 0000000000001769 RCX: 00007fd139f84e57
RDX: 0000000040000000 RSI: 00007ffc38914c4c RDI: 00000000ffffffff
RBP: 00007ffc38914c4c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 00007ffc38914cd0
R13: 00007ffc38914cd8 R14: 0000000000000009 R15: 0000000000000000