rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=dd1/1/0x4000000000000000 softirq=142789/142794 fqs=3 (detected by 0, t=10502 jiffies, g=250485, q=31) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 29939 Comm: syz-executor.0 Not tainted 5.16.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:lockdep_recursion_finish kernel/locking/lockdep.c:438 [inline] RIP: 0010:lock_acquire kernel/locking/lockdep.c:5639 [inline] RIP: 0010:lock_acquire+0x1c8/0x510 kernel/locking/lockdep.c:5602 Code: 41 0f 94 c1 45 0f b6 c9 e8 d5 96 ff ff 48 c7 c7 e0 0e ac 89 48 83 c4 20 e8 15 36 f5 07 b8 ff ff ff ff 65 0f c1 05 08 76 a5 7e <83> f8 01 0f 85 b4 02 00 00 9c 58 f6 c4 02 0f 85 9f 02 00 00 48 83 RSP: 0018:ffffc90000dc0cd0 EFLAGS: 00000057 RAX: 0000000000000001 RBX: 1ffff920001b819c RCX: ffffffff815cb15f RDX: 1ffff11006b2988b RSI: 0000000000010001 RDI: 0000000000000000 RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff8ff76be7 R10: fffffbfff1feed7c R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffff888033ff0b00 R15: 0000000000000000 FS: 00007f26e28f8700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2da32000 CR3: 000000009578b000 CR4: 0000000000350ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:349 [inline] advance_sched+0x53/0x9a0 net/sched/sch_taprio.c:714 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x609/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:__skb_clone+0x5d0/0x780 net/core/skbuff.c:1085 Code: 48 89 ea 48 c1 ea 03 0f b6 04 02 48 89 ea 83 e2 07 38 d0 7f 04 84 c0 75 61 80 4b 7e 01 48 83 c4 08 4c 89 e0 5b 5d 41 5c 41 5d <41> 5e 41 5f c3 e8 86 98 45 fa 48 8d 7b 7a 48 b8 00 00 00 00 00 fc RSP: 0018:ffffc900053e7030 EFLAGS: 00000292 RAX: ffff88803ae72d68 RBX: 0000000000000000 RCX: ffffffff87324f17 RDX: 0000000000000006 RSI: 0000000000000004 RDI: ffff8880407dd6e0 RBP: ffff88803ae72c80 R08: 0000000000000001 R09: ffff8880407dd6e3 R10: ffffed10080fbadc R11: 0000000000000000 R12: ffff88803ae72d68 R13: 0000000000000a20 R14: ffff88803ae72d44 R15: ffff88803ae72e44 skb_clone+0x1c3/0x3c0 net/core/skbuff.c:1528 tipc_msg_reassemble+0x130/0x4f0 net/tipc/msg.c:780 tipc_mcast_xmit+0x5ea/0x1190 net/tipc/bcast.c:392 tipc_sendmcast+0xa2a/0xdd0 net/tipc/socket.c:886 __tipc_sendmsg+0x1083/0x17e0 net/tipc/socket.c:1466 tipc_sendmsg+0x4c/0x70 net/tipc/socket.c:1402 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 sock_no_sendpage+0xf6/0x140 net/core/sock.c:3080 kernel_sendpage.part.0+0x1a0/0x340 net/socket.c:3504 kernel_sendpage net/socket.c:3501 [inline] sock_sendpage+0xe5/0x140 net/socket.c:1003 pipe_to_sendpage+0x2ad/0x380 fs/splice.c:364 splice_from_pipe_feed fs/splice.c:418 [inline] __splice_from_pipe+0x43e/0x8a0 fs/splice.c:562 splice_from_pipe fs/splice.c:597 [inline] generic_splice_sendpage+0xd4/0x140 fs/splice.c:746 do_splice_from fs/splice.c:767 [inline] direct_splice_actor+0x110/0x180 fs/splice.c:936 splice_direct_to_actor+0x34b/0x8c0 fs/splice.c:891 do_splice_direct+0x1b3/0x280 fs/splice.c:979 do_sendfile+0xaf2/0x1250 fs/read_write.c:1245 __do_sys_sendfile64 fs/read_write.c:1310 [inline] __se_sys_sendfile64 fs/read_write.c:1296 [inline] __x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1296 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f26e5382ae9 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f26e28f8188 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f26e5495f60 RCX: 00007f26e5382ae9 RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000005 RBP: 00007f26e53dcf6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000200fc0 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd8a0ca6bf R14: 00007f26e28f8300 R15: 0000000000022000 rcu: rcu_preempt kthread starved for 10495 jiffies! g250485 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:28688 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4972 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6253 schedule+0xd2/0x260 kernel/sched/core.c:6326 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1955 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2128 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 0 CPU: 0 PID: 12773 Comm: kworker/u4:3 Not tainted 5.16.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound toggle_allocation_gate Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_check_gp_kthread_starvation.cold+0x1fb/0x200 kernel/rcu/tree_stall.h:481 print_other_cpu_stall kernel/rcu/tree_stall.h:586 [inline] check_cpu_stall kernel/rcu/tree_stall.h:729 [inline] rcu_pending kernel/rcu/tree.c:3878 [inline] rcu_sched_clock_irq+0x2125/0x2200 kernel/rcu/tree.c:2597 update_process_times+0x16d/0x200 kernel/time/timer.c:1785 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1421 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:__sanitizer_cov_trace_const_cmp4+0xc/0x70 kernel/kcov.c:286 Code: 00 00 00 48 89 7c 30 e8 48 89 4c 30 f0 4c 89 54 d8 20 48 89 10 5b c3 0f 1f 80 00 00 00 00 41 89 f8 bf 03 00 00 00 4c 8b 14 24 <89> f1 65 48 8b 34 25 40 70 02 00 e8 14 f9 ff ff 84 c0 74 4b 48 8b RSP: 0018:ffffc90002e2f9f0 EFLAGS: 00000202 RAX: 0000000000000001 RBX: ffff8880b9d3fca0 RCX: 0000000000000000 RDX: ffff888042391d00 RSI: 0000000000000001 RDI: 0000000000000003 RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff816c7286 R11: 0000000000000000 R12: ffffed10173a7f95 R13: 0000000000000001 R14: ffff8880b9d3fca8 R15: 0000000000000001 csd_lock_wait kernel/smp.c:440 [inline] smp_call_function_many_cond+0x476/0xc20 kernel/smp.c:969 on_each_cpu_cond_mask+0x56/0xa0 kernel/smp.c:1135 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1112 [inline] text_poke_bp_batch+0x1b3/0x560 arch/x86/kernel/alternative.c:1297 text_poke_flush arch/x86/kernel/alternative.c:1451 [inline] text_poke_flush arch/x86/kernel/alternative.c:1448 [inline] text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1458 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146 jump_label_update+0x1d5/0x430 kernel/jump_label.c:830 static_key_enable_cpuslocked+0x1b1/0x260 kernel/jump_label.c:177 static_key_enable+0x16/0x20 kernel/jump_label.c:190 toggle_allocation_gate mm/kfence/core.c:732 [inline] toggle_allocation_gate+0x100/0x390 mm/kfence/core.c:724 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess): 0: 41 0f 94 c1 sete %r9b 4: 45 0f b6 c9 movzbl %r9b,%r9d 8: e8 d5 96 ff ff callq 0xffff96e2 d: 48 c7 c7 e0 0e ac 89 mov $0xffffffff89ac0ee0,%rdi 14: 48 83 c4 20 add $0x20,%rsp 18: e8 15 36 f5 07 callq 0x7f53632 1d: b8 ff ff ff ff mov $0xffffffff,%eax 22: 65 0f c1 05 08 76 a5 xadd %eax,%gs:0x7ea57608(%rip) # 0x7ea57632 29: 7e * 2a: 83 f8 01 cmp $0x1,%eax <-- trapping instruction 2d: 0f 85 b4 02 00 00 jne 0x2e7 33: 9c pushfq 34: 58 pop %rax 35: f6 c4 02 test $0x2,%ah 38: 0f 85 9f 02 00 00 jne 0x2dd 3e: 48 rex.W 3f: 83 .byte 0x83