rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 0-...!: (1 GPs behind) idle=4a3/1/0x4000000000000000 softirq=99144/99145 fqs=5 (detected by 1, t=10502 jiffies, g=165841, q=101) Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 11202 Comm: syz-executor.3 Not tainted 5.16.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:40 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:75 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:107 [inline] RIP: 0010:lock_is_held_type+0x54/0x140 kernel/locking/lockdep.c:5676 Code: c0 0f 85 ca 00 00 00 65 4c 8b 24 25 40 70 02 00 41 8b 94 24 5c 0a 00 00 85 d2 0f 85 b1 00 00 00 48 89 fd 41 89 f6 9c 8f 04 24 48 c7 c7 20 10 ac 89 31 db e8 1d 0e 00 00 41 8b 84 24 58 0a 00 RSP: 0018:ffffc90000007bf8 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffffffff8bb83be0 RBP: ffffffff8bb83be0 R08: 0000000000000000 R09: ffffffff8d912157 R10: fffffbfff1b2242a R11: 0000000000000000 R12: ffff88807a119d00 R13: 00000000ffffffff R14: 00000000ffffffff R15: ffffffff89ae0500 FS: 00007febd09a1700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fcdfe0f6018 CR3: 0000000096485000 CR4: 0000000000350ef0 Call Trace: lock_is_held include/linux/lockdep.h:283 [inline] rcu_read_lock_sched_held+0x3a/0x70 kernel/rcu/update.c:125 trace_lock_release include/trace/events/lock.h:58 [inline] lock_release+0x522/0x720 kernel/locking/lockdep.c:5648 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline] _raw_spin_unlock_irqrestore+0x16/0x70 kernel/locking/spinlock.c:194 debug_object_activate+0x287/0x3e0 lib/debugobjects.c:689 debug_hrtimer_activate kernel/time/hrtimer.c:420 [inline] debug_activate kernel/time/hrtimer.c:475 [inline] enqueue_hrtimer+0x27/0x3e0 kernel/time/hrtimer.c:1084 __run_hrtimer kernel/time/hrtimer.c:1702 [inline] __hrtimer_run_queues+0xb02/0xe50 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:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:read_mems_allowed_begin include/linux/cpuset.h:151 [inline] RIP: 0010:get_any_partial mm/slub.c:2213 [inline] RIP: 0010:get_partial mm/slub.c:2256 [inline] RIP: 0010:___slab_alloc+0x2c9/0xfe0 mm/slub.c:3017 Code: ff ff ff 00 0f 85 7d 01 00 00 9c 58 f6 c4 02 0f 85 2d 08 00 00 48 83 bd 68 ff ff ff 00 44 8b ad 70 ff ff ff 0f 85 57 01 00 00 <65> 48 8b 04 25 40 70 02 00 44 89 ad 70 ff ff ff 48 89 85 38 ff ff RSP: 0018:ffffc9001625fa00 EFLAGS: 00000206 RAX: 0000000000000006 RBX: ffffe8ffffc036e0 RCX: 1ffffffff1ffa896 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc9001625fae0 R08: 0000000000000001 R09: ffffffff8ff71b07 R10: 0000000000000001 R11: ffffffff81bddf4c R12: ffff888144a94500 R13: 00000000ffffffff R14: 0000000000000000 R15: ffffea00013f3ec0 kmem_cache_alloc_bulk+0x21a/0x720 mm/slub.c:3706 __io_alloc_req_refill fs/io_uring.c:1976 [inline] io_alloc_req_refill fs/io_uring.c:2002 [inline] io_submit_sqes.cold+0x20b/0x43d fs/io_uring.c:7312 __do_sys_io_uring_enter+0xf6e/0x1f50 fs/io_uring.c:10039 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: 0033:0x7febd342bae9 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:00007febd09a1188 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: ffffffffffffffda RBX: 00007febd353ef60 RCX: 00007febd342bae9 RDX: 0000000000000000 RSI: 0000000000002039 RDI: 0000000000000004 RBP: 00007febd3485f6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd67ba338f R14: 00007febd09a1300 R15: 0000000000022000 rcu: rcu_preempt kthread starved for 10492 jiffies! g165841 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:28440 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 1 CPU: 1 PID: 11209 Comm: syz-executor.5 Not tainted 5.16.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 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+0x1b3/0x230 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: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:csd_lock_wait kernel/smp.c:440 [inline] RIP: 0010:smp_call_function_many_cond+0x452/0xc20 kernel/smp.c:969 Code: 0b 00 85 ed 74 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 f4 4c 89 f5 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 80 75 0b 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 33 06 00 00 8b 43 08 31 RSP: 0018:ffffc90016437708 EFLAGS: 00000246 RAX: 0000000000040000 RBX: ffff8880b9c41d40 RCX: ffffc90013d60000 RDX: 0000000000040000 RSI: ffffffff816c23e0 RDI: 0000000000000003 RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff816c2406 R11: 0000000000000000 R12: ffffed10173883a9 R13: 0000000000000000 R14: ffff8880b9c41d48 R15: 0000000000000001 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_bp+0xad/0x110 arch/x86/kernel/alternative.c:1497 arch_static_call_transform+0x4d/0x90 arch/x86/kernel/static_call.c:107 __static_call_update+0xcf/0x620 kernel/static_call.c:136 tracepoint_update_call kernel/tracepoint.c:317 [inline] tracepoint_add_func+0xa18/0xe50 kernel/tracepoint.c:358 tracepoint_probe_register_prio kernel/tracepoint.c:511 [inline] tracepoint_probe_register+0xa1/0xf0 kernel/tracepoint.c:531 trace_event_reg+0x28f/0x350 kernel/trace/trace_events.c:513 perf_trace_event_reg kernel/trace/trace_event_perf.c:129 [inline] perf_trace_event_init+0x54a/0xa20 kernel/trace/trace_event_perf.c:204 perf_trace_init+0x1a0/0x2f0 kernel/trace/trace_event_perf.c:228 perf_tp_event_init+0xa2/0x120 kernel/events/core.c:9791 perf_try_init_event+0x12a/0x560 kernel/events/core.c:11249 perf_init_event kernel/events/core.c:11313 [inline] perf_event_alloc.part.0+0xf21/0x3b10 kernel/events/core.c:11604 perf_event_alloc kernel/events/core.c:12027 [inline] __do_sys_perf_event_open+0x4ae/0x3130 kernel/events/core.c:12125 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: 0033:0x7fb8708b0ae9 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:00007fb86de26188 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007fb8709c3f60 RCX: 00007fb8708b0ae9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200001c0 RBP: 00007fb87090af6d R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd4e26010f R14: 00007fb86de26300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: c0 0f 85 rorb $0x85,(%rdi) 3: ca 00 00 lret $0x0 6: 00 65 4c add %ah,0x4c(%rbp) 9: 8b 24 25 40 70 02 00 mov 0x27040,%esp 10: 41 8b 94 24 5c 0a 00 mov 0xa5c(%r12),%edx 17: 00 18: 85 d2 test %edx,%edx 1a: 0f 85 b1 00 00 00 jne 0xd1 20: 48 89 fd mov %rdi,%rbp 23: 41 89 f6 mov %esi,%r14d 26: 9c pushfq 27: 8f 04 24 popq (%rsp) * 2a: fa cli <-- trapping instruction 2b: 48 c7 c7 20 10 ac 89 mov $0xffffffff89ac1020,%rdi 32: 31 db xor %ebx,%ebx 34: e8 1d 0e 00 00 callq 0xe56 39: 41 rex.B 3a: 8b .byte 0x8b 3b: 84 24 58 test %ah,(%rax,%rbx,2) 3e: 0a 00 or (%rax),%al