rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 0-....: (10479 ticks this GP) idle=01fc/1/0x4000000000000000 softirq=94864/94867 fqs=30
rcu: hardirqs softirqs csw/system
rcu: number: 120080 0 0
rcu: cputime: 2538 492 1 ==> 3070(ms)
rcu: (t=10503 jiffies g=121421 q=3061 ncpus=2)
rcu: rcu_preempt kthread starved for 303 jiffies! g121421 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:26824 pid:17 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x15ae/0x4660 kernel/sched/core.c:6701
schedule+0xbd/0x170 kernel/sched/core.c:6775
schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168
rcu_gp_fqs_loop+0x30d/0x1590 kernel/rcu/tree.c:1667
rcu_gp_kthread+0x9d/0x3b0 kernel/rcu/tree.c:1866
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 7447 Comm: kworker/u4:21 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: writeback wb_workfn (flush-8:0)
RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline]
RIP: 0010:smp_call_function_many_cond+0xd96/0x1190 kernel/smp.c:855
Code: 41 83 e6 01 49 be 00 00 00 00 00 fc ff df 75 07 e8 4f fd 0a 00 eb 38 f3 90 42 0f b6 04 33 84 c0 75 11 41 f7 04 24 01 00 00 00 <74> 1e e8 33 fd 0a 00 eb e4 44 89 e1 80 e1 07 80 c1 03 38 c1 7c e2
RSP: 0000:ffffc90004b1e300 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 1ffff110171c87ad RCX: ffff888018fdda00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90004b1e480 R08: ffffffff8e8c772f R09: 1ffffffff1d18ee5
R10: dffffc0000000000 R11: fffffbfff1d18ee6 R12: ffff8880b8e43d68
R13: ffff8880b8f3d3c0 R14: dffffc0000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f067beb7080 CR3: 000000002db64000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1022
__flush_tlb_multi arch/x86/include/asm/paravirt.h:87 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:990 [inline]
flush_tlb_mm_range+0x417/0x680 arch/x86/mm/tlb.c:1078
flush_tlb_page arch/x86/include/asm/tlbflush.h:255 [inline]
ptep_clear_flush+0x120/0x170 mm/pgtable-generic.c:101
page_vma_mkclean_one+0x43c/0x730 mm/rmap.c:962
page_mkclean_one+0x202/0x3e0 mm/rmap.c:1003
rmap_walk_file+0x38d/0x770 mm/rmap.c:2500
rmap_walk mm/rmap.c:2518 [inline]
folio_mkclean+0x1e5/0x360 mm/rmap.c:1035
folio_clear_dirty_for_io+0x20c/0xca0 mm/page-writeback.c:2918
mpage_submit_folio+0x77/0x3c0 fs/ext4/inode.c:1892
mpage_process_page_bufs+0x6bf/0x8c0 fs/ext4/inode.c:2024
mpage_prepare_extent_to_map+0xdd3/0x1d50 fs/ext4/inode.c:2532
ext4_do_writepages+0xb46/0x3990 fs/ext4/inode.c:2674
ext4_writepages+0x1dd/0x350 fs/ext4/inode.c:2810
do_writepages+0x351/0x590 mm/page-writeback.c:2575
__writeback_single_inode+0x14e/0xee0 fs/fs-writeback.c:1686
writeback_sb_inodes+0x813/0x1020 fs/fs-writeback.c:1977
__writeback_inodes_wb+0x114/0x240 fs/fs-writeback.c:2048
wb_writeback+0x472/0xbe0 fs/fs-writeback.c:2158
wb_check_old_data_flush fs/fs-writeback.c:2262 [inline]
wb_do_writeback fs/fs-writeback.c:2315 [inline]
wb_workfn+0xad7/0xe60 fs/fs-writeback.c:2343
process_one_work kernel/workqueue.c:2657 [inline]
process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2734
worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2815
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
CPU: 0 PID: 21383 Comm: syz.3.5345 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:unwind_next_frame+0x645/0x2990 arch/x86/kernel/unwind_orc.c:505
Code: 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 e0 1c 00 00 4c 89 e0 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 ec 1c 00 00 45 0f b6 76 01 <41> 83 e6 07 4c 89 f7 48 c7 c6 a0 05 fa 8c e8 b8 cc 4b 00 4d 85 f6
RSP: 0018:ffffc90000006f78 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffffff8f0e6962 RCX: ffff888024a55a00
RDX: 0000000000000100 RSI: ffffffff8130f5ef RDI: ffffffff8130f5fb
RBP: ffffc90000007098 R08: ffffc90000007110 R09: 0000000000000014
R10: 0000000000000004 R11: 0000000000000100 R12: ffffffff8f0e6967
R13: ffffc90000007048 R14: 0000000000000002 R15: dffffc0000000000
FS: 00007f9c7e2516c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f217ff8 CR3: 0000000026f77000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122
kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46
__kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492
__call_rcu_common kernel/rcu/tree.c:2721 [inline]
call_rcu+0x153/0x900 kernel/rcu/tree.c:2837
refdst_drop include/net/dst.h:270 [inline]
skb_dst_drop include/net/dst.h:282 [inline]
__dev_queue_xmit+0x801/0x3630 net/core/dev.c:4405
neigh_output include/net/neighbour.h:547 [inline]
ip6_finish_output2+0xe2e/0x1620 net/ipv6/ip6_output.c:141
dst_output include/net/dst.h:467 [inline]
NF_HOOK include/linux/netfilter.h:304 [inline]
ndisc_send_skb+0xbb9/0x1480 net/ipv6/ndisc.c:513
addrconf_rs_timer+0x36b/0x640 net/ipv6/addrconf.c:4036
call_timer_fn+0x189/0x540 kernel/time/timer.c:1701
expire_timers kernel/time/timer.c:1752 [inline]
__run_timers+0x570/0x810 kernel/time/timer.c:2023
run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2036
handle_softirqs+0x27d/0x820 kernel/softirq.c:578
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661
irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:__schedule+0x0/0x4660 kernel/sched/core.c:6580
Code: cc cc cc cc cc cc cc cc cc cc f3 0f 1e fa be 01 00 00 00 48 c7 c7 e0 9e 74 8e e8 1b d5 48 f7 c3 cc cc cc cc cc cc cc cc cc cc 0f 1e fa 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48
RSP: 0018:ffffc9000ed977b8 EFLAGS: 00000282
RAX: 863633d210267400 RBX: 0000000000000000 RCX: 863633d210267400
RDX: dffffc0000000000 RSI: ffffffff8acacbe0 RDI: 0000000000000001
RBP: ffffc9000ed97860 R08: ffffffff911ed507 R09: 1ffffffff223daa0
R10: dffffc0000000000 R11: fffffbfff223daa1 R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92001db2ef8
preempt_schedule_irq+0xbf/0x150 kernel/sched/core.c:7011
irqentry_exit+0x67/0x70 kernel/entry/common.c:438
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:text_poke_bp_batch+0x2f9/0x980 arch/x86/kernel/alternative.c:-1
Code: f5 fe ff ff 48 c7 c1 ec ab 8c 8e 80 e1 07 80 c1 03 38 c1 0f 8c f7 fe ff ff 48 c7 c7 ec ab 8c 8e e8 6c f4 ae 00 e9 e6 fe ff ff <48> c7 44 24 30 00 00 00 00 31 ff 48 c7 c6 80 f5 30 81 31 d2 b9 01
RSP: 0018:ffffc9000ed97920 EFLAGS: 00000246
RAX: ffffffff8169086a RBX: 0000000000000000 RCX: 863633d210267400
RDX: 0000000000000006 RSI: ffffffff8acadd60 RDI: ffffffff8b1d32e0
RBP: ffffc9000ed97a48 R08: ffffffff8e8c772f R09: 1ffffffff1d18ee5
R10: dffffc0000000000 R11: fffffbfff1d18ee6 R12: dffffc0000000000
R13: 000000000000000f R14: ffffffff900cabc0 R15: ffffffff8169086a
text_poke_flush arch/x86/kernel/alternative.c:2623 [inline]
text_poke_finish+0x30/0x50 arch/x86/kernel/alternative.c:2630
arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
static_key_enable_cpuslocked+0x123/0x240 kernel/jump_label.c:207
static_key_enable+0x1a/0x20 kernel/jump_label.c:220
tracepoint_add_func+0x985/0xa10 kernel/tracepoint.c:363
tracepoint_probe_register_prio kernel/tracepoint.c:513 [inline]
tracepoint_probe_register+0x5e/0x90 kernel/tracepoint.c:533
perf_trace_event_reg kernel/trace/trace_event_perf.c:129 [inline]
perf_trace_event_init+0x4d4/0x9b0 kernel/trace/trace_event_perf.c:202
perf_trace_init+0x238/0x2d0 kernel/trace/trace_event_perf.c:226
perf_tp_event_init+0x8d/0x110 kernel/events/core.c:10228
perf_try_init_event+0x12b/0x3c0 kernel/events/core.c:11852
perf_init_event kernel/events/core.c:11922 [inline]
perf_event_alloc+0xed4/0x2150 kernel/events/core.c:12203
__do_sys_perf_event_open kernel/events/core.c:12710 [inline]
__se_sys_perf_event_open+0x740/0x1c60 kernel/events/core.c:12601
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f9c7d39e0d9
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:00007f9c7e251028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007f9c7d625fa0 RCX: 00007f9c7d39e0d9
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000040
RBP: 00007f9c7d435024 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9c7d626038 R14: 00007f9c7d625fa0 R15: 00007fff2c7e8868