rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 ticks this GP) idle=26b/1/0x4000000000000000 softirq=5252/5252 fqs=1 (detected by 1, t=10504 jiffies, g=4849, q=69 ncpus=2) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3624 Comm: syz-executor101 Not tainted 5.19.0-rc5-syzkaller-00049-gc1084b6c5620 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022 RIP: 0010:check_preemption_disabled+0x28/0x170 lib/smp_processor_id.c:16 Code: cc cc 41 56 41 55 49 89 f5 41 54 55 48 89 fd 53 0f 1f 44 00 00 65 44 8b 25 35 0b 8b 76 65 8b 1d 9e 60 8b 76 81 e3 ff ff ff 7f <31> ff 89 de 0f 1f 44 00 00 85 db 74 11 0f 1f 44 00 00 44 89 e0 5b RSP: 0018:ffffc90000007c60 EFLAGS: 00000006 RAX: 0000000000000000 RBX: 0000000000010203 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff89cc6700 RDI: ffffffff8a283480 RBP: ffffffff8a283480 R08: 0000000000000000 R09: ffffffff8dbae9d7 R10: fffffbfff1b75d3a R11: 0000000000000001 R12: 0000000000000000 R13: ffffffff89cc6700 R14: 00000000ffffffff R15: 0000000000000000 FS: 0000555556020300(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000600 CR3: 0000000021949000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_inc kernel/locking/lockdep.c:461 [inline] lock_is_held_type+0x63/0x140 kernel/locking/lockdep.c:5707 lock_is_held include/linux/lockdep.h:279 [inline] rcu_read_lock_sched_held+0x3a/0x70 kernel/rcu/update.c:125 trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0x480/0x570 kernel/locking/lockdep.c:5636 rcu_lock_acquire include/linux/rcupdate.h:269 [inline] rcu_read_lock include/linux/rcupdate.h:695 [inline] advance_sched+0x4a5/0x9a0 net/sched/sch_taprio.c:768 __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:1095 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1112 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x38/0x70 kernel/locking/spinlock.c:194 Code: 74 24 10 e8 9a 6c e3 f7 48 89 ef e8 a2 ed e3 f7 81 e3 00 02 00 00 75 25 9c 58 f6 c4 02 75 2d 48 85 db 74 01 fb bf 01 00 00 00 43 f6 d6 f7 65 8b 05 dc 5e 88 76 85 c0 74 0a 5b 5d c3 e8 90 d5 RSP: 0018:ffffc900030771e0 EFLAGS: 00000206 RAX: 0000000000000002 RBX: 0000000000000200 RCX: 1ffffffff20d8b9e RDX: 0000000000000000 RSI: 0000000000000202 RDI: 0000000000000001 RBP: ffff8880221faae8 R08: 0000000000000001 R09: ffffffff9067b9c7 R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000 R13: ffff8880221faae8 R14: 0000000000000246 R15: ffff8880221fa800 spin_unlock_irqrestore include/linux/spinlock.h:404 [inline] taprio_change+0x2eab/0x4050 net/sched/sch_taprio.c:1607 taprio_init+0x52e/0x670 net/sched/sch_taprio.c:1739 qdisc_create.constprop.0+0x44a/0x10f0 net/sched/sch_api.c:1253 tc_modify_qdisc+0x4c5/0x1a00 net/sched/sch_api.c:1660 rtnetlink_rcv_msg+0x43a/0xc90 net/core/rtnetlink.c:6089 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2501 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x543/0x7f0 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x917/0xe10 net/netlink/af_netlink.c:1921 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:734 ____sys_sendmsg+0x6eb/0x810 net/socket.c:2488 ___sys_sendmsg+0xf3/0x170 net/socket.c:2542 __sys_sendmsg net/socket.c:2571 [inline] __do_sys_sendmsg net/socket.c:2580 [inline] __se_sys_sendmsg net/socket.c:2578 [inline] __x64_sys_sendmsg+0x132/0x220 net/socket.c:2578 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+0x46/0xb0 RIP: 0033:0x7fd81f272eb9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 41 15 00 00 90 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 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffd6474f468 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fd81f272eb9 RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000004 RBP: 0000000000000000 R08: 000000000000000d R09: 000000000000000d R10: 000000000000000d R11: 0000000000000246 R12: 00007ffd6474f480 R13: 00000000000f4240 R14: 0000000000000000 R15: 0000000000000000 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.067 msecs rcu: rcu_preempt kthread starved for 10498 jiffies! g4849 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:28112 pid: 16 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5146 [inline] __schedule+0xa00/0x4b50 kernel/sched/core.c:6458 schedule+0xd2/0x1f0 kernel/sched/core.c:6530 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1935 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1999 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2187 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 1 CPU: 1 PID: 56 Comm: kworker/u4:4 Not tainted 5.19.0-rc5-syzkaller-00049-gc1084b6c5620 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022 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:111 nmi_trigger_cpumask_backtrace+0x1e6/0x230 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:518 print_other_cpu_stall kernel/rcu/tree_stall.h:623 [inline] check_cpu_stall kernel/rcu/tree_stall.h:769 [inline] rcu_pending kernel/rcu/tree.c:3977 [inline] rcu_sched_clock_irq+0x2311/0x2370 kernel/rcu/tree.c:2675 update_process_times+0x11a/0x1a0 kernel/time/timer.c:1839 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:243 tick_sched_timer+0xee/0x120 kernel/time/tick-sched.c:1480 __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:1095 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1112 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:csd_lock_wait kernel/smp.c:414 [inline] RIP: 0010:smp_call_function_many_cond+0x499/0x1110 kernel/smp.c:988 Code: 01 89 ee e8 69 98 0a 00 85 ed 74 47 48 8b 04 24 49 89 c4 83 e0 07 49 c1 ec 03 48 89 c5 4d 01 fc 83 c5 03 e8 09 9c 0a 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 21 0a 00 00 8b 43 08 31 RSP: 0018:ffffc90001c2f950 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffffe8ffffc0bd20 RCX: 0000000000000000 RDX: ffff8880182021c0 RSI: ffffffff816efb77 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: fffff91ffff817a5 R13: 0000000000000000 R14: 0000000000000001 R15: dffffc0000000000 on_each_cpu_cond_mask+0x56/0xa0 kernel/smp.c:1154 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1231 [inline] text_poke_bp_batch+0x233/0x6c0 arch/x86/kernel/alternative.c:1419 text_poke_flush arch/x86/kernel/alternative.c:1589 [inline] text_poke_flush arch/x86/kernel/alternative.c:1586 [inline] text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1596 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146 jump_label_update+0x32f/0x410 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:811 [inline] toggle_allocation_gate+0x100/0x390 mm/kfence/core.c:803 process_one_work+0x996/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302 ---------------- Code disassembly (best guess): 0: cc int3 1: cc int3 2: 41 56 push %r14 4: 41 55 push %r13 6: 49 89 f5 mov %rsi,%r13 9: 41 54 push %r12 b: 55 push %rbp c: 48 89 fd mov %rdi,%rbp f: 53 push %rbx 10: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 15: 65 44 8b 25 35 0b 8b mov %gs:0x768b0b35(%rip),%r12d # 0x768b0b52 1c: 76 1d: 65 8b 1d 9e 60 8b 76 mov %gs:0x768b609e(%rip),%ebx # 0x768b60c2 24: 81 e3 ff ff ff 7f and $0x7fffffff,%ebx * 2a: 31 ff xor %edi,%edi <-- trapping instruction 2c: 89 de mov %ebx,%esi 2e: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 33: 85 db test %ebx,%ebx 35: 74 11 je 0x48 37: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 3c: 44 89 e0 mov %r12d,%eax 3f: 5b pop %rbx