rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (10 ticks this GP) idle=9cd4/1/0x4000000000000000 softirq=10535/10536 fqs=12
rcu: (detected by 0, t=10502 jiffies, g=8237, q=43 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5910 Comm: syz.1.12 Not tainted 6.6.102-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:hlock_class kernel/locking/lockdep.c:223 [inline]
RIP: 0010:mark_lock+0x5d/0x320 kernel/locking/lockdep.c:4656
Code: c0 0f 85 74 02 00 00 41 0f b6 47 02 24 03 3c 01 bd 09 00 00 00 83 dd 00 41 bc 01 00 00 00 89 e9 41 d3 e4 4d 8d 7e 20 4c 89 f8 <48> c1 e8 03 42 0f b6 04 28 84 c0 0f 85 22 02 00 00 41 8b 07 41 89
RSP: 0018:ffffc900001efcc0 EFLAGS: 00000006
RAX: ffff888023ffc7c8 RBX: ffff888023ffbc00 RCX: 0000000000000009
RDX: 0000000000000008 RSI: ffff888023ffc7a8 RDI: ffff888023ffbc00
RBP: 0000000000000009 R08: dffffc0000000000 R09: 1ffffffff21b46a0
R10: dffffc0000000000 R11: fffffbfff21b46a1 R12: 0000000000000200
R13: dffffc0000000000 R14: ffff888023ffc7a8 R15: ffff888023ffc7c8
FS: 00007fa574c1d6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000033000 CR3: 0000000021065000 CR4: 00000000003506e0
Call Trace:
mark_usage kernel/locking/lockdep.c:4599 [inline]
__lock_acquire+0xd49/0x7c80 kernel/locking/lockdep.c:5091
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
rcu_read_lock include/linux/rcupdate.h:786 [inline]
__perf_event_output kernel/events/core.c:7969 [inline]
perf_event_output_forward+0xb5/0x3a0 kernel/events/core.c:7992
__perf_event_overflow+0x447/0x630 kernel/events/core.c:9717
perf_swevent_overflow kernel/events/core.c:9793 [inline]
perf_swevent_event+0x2f5/0x5c0 kernel/events/core.c:-1
perf_tp_event+0x4f9/0x13a0 kernel/events/core.c:10343
perf_trace_run_bpf_submit+0xf4/0x1c0 kernel/events/core.c:10267
perf_trace_preemptirq_template+0x281/0x340 include/trace/events/preemptirq.h:14
trace_irq_enable+0xbf/0xe0 include/trace/events/preemptirq.h:40
trace_hardirqs_on+0x18/0x40 kernel/trace/trace_preemptirq.c:56
asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:723
RIP: 0010:rcu_read_unlock_special+0x88/0x4c0 kernel/rcu/tree_plugin.h:682
Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 39 58 93 7e 41 f7 c6 00 00 f0 00 74 45 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0018:ffffc900001f0780 EFLAGS: 00000206
RAX: 57bb0f3337ae4600 RBX: 1ffff9200003e0f8 RCX: 57bb0f3337ae4600
RDX: dffffc0000000000 RSI: ffffffff8aaab9c0 RDI: ffffffff8afc66c0
RBP: ffffc900001f0878 R08: ffffffff90da35c7 R09: 1ffffffff21b46b8
R10: dffffc0000000000 R11: fffffbfff21b46b9 R12: ffffffff8cd35400
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000002
__rcu_read_unlock+0x7c/0xd0 kernel/rcu/tree_plugin.h:426
rcu_read_unlock include/linux/rcupdate.h:818 [inline]
__ip_queue_xmit+0x112b/0x1a10 net/ipv4/ip_output.c:536
__tcp_transmit_skb+0x1c97/0x32a0 net/ipv4/tcp_output.c:1422
tcp_delack_timer_handler+0x2ad/0x440 net/ipv4/tcp_timer.c:330
tcp_delack_timer+0x18c/0x2e0 net/ipv4/tcp_timer.c:353
call_timer_fn+0x16e/0x530 kernel/time/timer.c:1700
expire_timers kernel/time/timer.c:1751 [inline]
__run_timers+0x52d/0x7d0 kernel/time/timer.c:2022
run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2035
handle_softirqs+0x280/0x820 kernel/softirq.c:578
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xc7/0x190 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:preempt_schedule_irq+0xb0/0x140 kernel/sched/core.c:7009
Code: 44 24 20 f6 44 24 21 02 74 0b 0f 0b 48 f7 03 08 00 00 00 74 63 bf 01 00 00 00 e8 4b da e5 f6 e8 46 5f 16 f7 fb bf 01 00 00 00 db b5 ff ff 48 c7 44 24 40 00 00 00 00 9c 8f 44 24 40 8b 44 24
RSP: 0018:ffffc90004c1ea60 EFLAGS: 00000286
RAX: 57bb0f3337ae4600 RBX: 0000000000000000 RCX: 57bb0f3337ae4600
RDX: dffffc0000000000 RSI: ffffffff8aaab9c0 RDI: 0000000000000001
RBP: ffffc90004c1eb10 R08: ffffffff90da3537 R09: 1ffffffff21b46a6
R10: dffffc0000000000 R11: fffffbfff21b46a7 R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92000983d4c
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:stack_trace_consume_entry+0x97/0x270 kernel/stacktrace.c:93
Code: 00 44 8b 23 45 85 e4 74 21 41 ff cc 41 0f b6 04 17 84 c0 0f 85 73 01 00 00 44 89 23 b0 01 e9 99 00 00 00 31 c0 e9 92 00 00 00 <48> 89 f8 48 c1 e8 03 80 3c 10 00 74 29 49 89 ff 48 89 74 24 08 49
RSP: 0018:ffffc90004c1ebd8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffc90004c1ecec RCX: ffff888023ffbc00
RDX: dffffc0000000000 RSI: ffffffff8a801256 RDI: ffffc90004c1ece0
RBP: 1ffff92000983d9e R08: ffffc90004c1ecf0 R09: 0000000000000009
R10: 0000000000000004 R11: 0000000000000002 R12: 0000000000000000
R13: 1ffff92000983d9d R14: ffffc90004c1ece8 R15: 1ffff92000983d9d
arch_stack_walk+0x138/0x190 arch/x86/kernel/stacktrace.c:27
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf7/0x1f0 mm/page_owner.c:128
__set_page_owner+0x1d/0x60 mm/page_owner.c:192
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554
prep_new_page mm/page_alloc.c:1561 [inline]
get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191
__alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457
__folio_alloc+0x10/0x20 mm/page_alloc.c:4489
vma_alloc_folio+0x47a/0x8f0 mm/mempolicy.c:2242
wp_page_copy mm/memory.c:3089 [inline]
do_wp_page+0x128e/0x3630 mm/memory.c:3468
handle_pte_fault mm/memory.c:5041 [inline]
__handle_mm_fault mm/memory.c:5166 [inline]
handle_mm_fault+0x12d4/0x4920 mm/memory.c:5331
do_user_addr_fault+0x738/0x12e0 arch/x86/mm/fault.c:1373
handle_page_fault arch/x86/mm/fault.c:1465 [inline]
exc_page_fault+0x67/0x110 arch/x86/mm/fault.c:1521
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0010:rep_movs_alternative+0x4a/0x90 arch/x86/lib/copy_user_64.S:71
Code: 75 f1 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 8b 06 48 89 07 48 83 c6 08 48 83 c7 08 83 e9 08 74 df 83 f9 08 73 e8 eb c9 a4 c3 48 8b 06 48 89 07 48 8d 47 08 48 83 e0 f8 48 29 f8 48 01
RSP: 0018:ffffc90004c1f718 EFLAGS: 00050206
RAX: ffffffff841bfa01 RBX: 1ffff92000983fc7 RCX: 000000000000db40
RDX: 0000000000000000 RSI: ffff88805cc82778 RDI: 0000200000033000
RBP: ffffc90004c1f878 R08: ffff88805cc902b7 R09: 1ffff1100b992056
R10: dffffc0000000000 R11: ffffed100b992057 R12: ffff88805cc800e8
R13: 00000000000101d0 R14: 00000000000101d0 R15: ffffc90004c1fe48
copy_user_generic arch/x86/include/asm/uaccess_64.h:112 [inline]
raw_copy_to_user arch/x86/include/asm/uaccess_64.h:133 [inline]
copyout lib/iov_iter.c:168 [inline]
_copy_to_iter+0x249/0x10d0 lib/iov_iter.c:316
__skb_datagram_iter+0xdb/0x780 net/core/datagram.c:419
skb_copy_datagram_iter+0xb1/0x200 net/core/datagram.c:535
skb_copy_datagram_msg include/linux/skbuff.h:4014 [inline]
tipc_recvstream+0x72b/0xe70 net/tipc/socket.c:2072
sock_recvmsg_nosec net/socket.c:1046 [inline]
sock_recvmsg net/socket.c:1068 [inline]
____sys_recvmsg+0x29e/0x5b0 net/socket.c:2814
___sys_recvmsg+0x1b6/0x510 net/socket.c:2856
__sys_recvmsg net/socket.c:2886 [inline]
__do_sys_recvmsg net/socket.c:2896 [inline]
__se_sys_recvmsg net/socket.c:2893 [inline]
__x64_sys_recvmsg+0x1f2/0x2c0 net/socket.c:2893
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fa573d8ebe9
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:00007fa574c1d038 EFLAGS: 00000246 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 00007fa573fb5fa0 RCX: 00007fa573d8ebe9
RDX: 0000000000001f00 RSI: 0000200000000500 RDI: 000000000000000c
RBP: 00007fa573e11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa573fb6038 R14: 00007fa573fb5fa0 R15: 00007ffefa30d358
rcu: rcu_preempt kthread timer wakeup didn't happen for 10476 jiffies! g8237 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=0 timer-softirq=4545
rcu: rcu_preempt kthread starved for 10477 jiffies! g8237 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:26920 pid:17 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
schedule+0xbd/0x170 kernel/sched/core.c:6773
schedule_timeout+0x160/0x280 kernel/time/timer.c:2167
rcu_gp_fqs_loop+0x302/0x1560 kernel/rcu/tree.c:1667
rcu_gp_kthread+0x99/0x380 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:
CPU: 0 PID: 5908 Comm: syz.1.12 Not tainted 6.6.102-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:148
Code: cc cc cc cc cc cc cc f3 0f 1e fa 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 66 90 0f 00 2d e3 e6 3a 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 66 0f 1f 00 55 41 57 41 56
RSP: 0018:ffffc90004bcf9d8 EFLAGS: 000002d3
RAX: ffffffff813a13aa RBX: 0000000000000003 RCX: ffff88802d9fda00
RDX: 0000000000000000 RSI: ffffffff8aaab9c0 RDI: ffffffff8afc66c0
RBP: ffffc90004bcfab0 R08: ffffffff90da35c7 R09: 1ffffffff21b46b8
R10: dffffc0000000000 R11: fffffbfff21b46b9 R12: dffffc0000000000
R13: 0000000000000200 R14: 0000000000000003 R15: 1ffff92000979f40
FS: 000055557e05d500(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2e10dff8 CR3: 0000000021065000 CR4: 00000000003506f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:108 [inline]
kvm_wait+0x22f/0x290 arch/x86/kernel/kvm.c:1058
pv_wait arch/x86/include/asm/paravirt.h:598 [inline]
pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline]
__pv_queued_spin_lock_slowpath+0x61a/0x9d0 kernel/locking/qspinlock.c:511
pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:586 [inline]
queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
do_raw_spin_lock+0x24e/0x2c0 kernel/locking/spinlock_debug.c:115
spin_lock_bh include/linux/spinlock.h:356 [inline]
lock_sock_nested+0x6a/0x100 net/core/sock.c:3513
lock_sock include/net/sock.h:1731 [inline]
tcp_close+0x1d/0x110 net/ipv4/tcp.c:2957
inet_release+0x13d/0x180 net/ipv4/af_inet.c:434
__sock_release net/socket.c:659 [inline]
sock_close+0xbd/0x230 net/socket.c:1421
__fput+0x234/0x970 fs/file_table.c:384
task_work_run+0x1ce/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fa573d8ebe9
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:00007ffefa30d4b8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007fa573fb7da0 RCX: 00007fa573d8ebe9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fa573fb7da0 R08: 0000000000015c9c R09: 00000017fa30d7af
R10: 00007fa573fb7cb0 R11: 0000000000000246 R12: 0000000000012af7
R13: 00007fa573fb6180 R14: ffffffffffffffff R15: 00007ffefa30d5d0