rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (10499 ticks this GP) idle=88d/1/0x4000000000000000 softirq=147924/147924 fqs=16 (t=10500 jiffies g=219733 q=625) rcu: rcu_preempt kthread starved for 10465 jiffies! g219733 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:28256 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: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 14520 Comm: kworker/u4:1 Not tainted 5.16.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:rep_nop arch/x86/include/asm/vdso/processor.h:13 [inline] RIP: 0010:cpu_relax arch/x86/include/asm/vdso/processor.h:18 [inline] RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline] RIP: 0010:smp_call_function_many_cond+0x450/0xc20 kernel/smp.c:969 Code: 76 7e 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 30 7c 0b 00 90 41 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 33 06 00 00 8b 43 RSP: 0018:ffffc90014c9f9f8 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b9d3dd40 RCX: 0000000000000000 RDX: ffff88809428e000 RSI: ffffffff816b6b70 RDI: 0000000000000003 RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff816b6b96 R11: 0000000000000000 R12: ffffed10173a7ba9 R13: 0000000000000001 R14: ffff8880b9d3dd48 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2ed21000 CR3: 000000000b88e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000009800 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: 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 NMI backtrace for cpu 1 CPU: 1 PID: 19815 Comm: syz-executor.0 Not tainted 5.16.0-rc5-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_dump_cpu_stacks+0x25e/0x3f0 kernel/rcu/tree_stall.h:343 print_cpu_stall kernel/rcu/tree_stall.h:627 [inline] check_cpu_stall kernel/rcu/tree_stall.h:711 [inline] rcu_pending kernel/rcu/tree.c:3878 [inline] rcu_sched_clock_irq.cold+0x9d/0x746 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:1428 __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+0x40/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 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 0a 9d 14 f8 48 89 ef e8 52 13 15 f8 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 93 db 07 f8 65 8b 05 8c 19 bb 76 85 c0 74 0a 5b 5d c3 e8 00 d6 RSP: 0018:ffffc90000fd8cc0 EFLAGS: 00000206 RAX: 0000000000000002 RBX: 0000000000000200 RCX: 1ffffffff1ffa026 RDX: 0000000000000000 RSI: 0000000000000101 RDI: 0000000000000001 RBP: ffff88809929bd08 R08: 0000000000000001 R09: ffffffff8ff77aef R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000 R13: ffff88809929bd08 R14: ffffffff874825a0 R15: 0000000000000000 spin_unlock_irqrestore include/linux/spinlock.h:404 [inline] skb_dequeue+0x125/0x180 net/core/skbuff.c:3216 mrp_queue_xmit net/802/mrp.c:363 [inline] mrp_join_timer+0x97/0xc0 net/802/mrp.c:608 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x675/0xa20 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:129 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline] RIP: 0010:kasan_check_range+0x55/0x180 mm/kasan/generic.c:189 Code: 86 05 01 00 00 49 83 e9 01 48 89 fd 48 b8 00 00 00 00 00 fc ff df 4d 89 ca 48 c1 ed 03 49 c1 ea 03 48 01 c5 49 01 c2 48 89 e8 <49> 8d 5a 01 48 89 da 48 29 ea 48 83 fa 10 7e 63 41 89 eb 41 83 e3 RSP: 0018:ffffc90003077868 EFLAGS: 00000282 RAX: fffffbfff17aaa2c RBX: 1ffff9200060ef12 RCX: ffffffff8946b616 RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffffff8bd55160 RBP: fffffbfff17aaa2c R08: 0000000000000001 R09: ffffffff8bd55167 R10: fffffbfff17aaa2c R11: 0000000000000001 R12: dffffc0000000000 R13: ffff88805166ca38 R14: ffff8880a4a05ae0 R15: 0000000000000000 instrument_atomic_read_write include/linux/instrumented.h:101 [inline] atomic_long_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1667 [inline] rwsem_write_trylock kernel/locking/rwsem.c:254 [inline] __down_write_common kernel/locking/rwsem.c:1267 [inline] __down_write kernel/locking/rwsem.c:1277 [inline] down_write+0xa6/0x150 kernel/locking/rwsem.c:1524 kernfs_activate+0x2a/0x1d0 fs/kernfs/dir.c:1293 kernfs_add_one+0x368/0x4c0 fs/kernfs/dir.c:766 __kernfs_create_file+0x29c/0x350 fs/kernfs/file.c:1014 sysfs_add_file_mode_ns+0x20f/0x3f0 fs/sysfs/file.c:294 create_files fs/sysfs/group.c:64 [inline] internal_create_group+0x322/0xb10 fs/sysfs/group.c:148 internal_create_groups.part.0+0x90/0x140 fs/sysfs/group.c:188 internal_create_groups fs/sysfs/group.c:184 [inline] sysfs_create_groups+0x25/0x50 fs/sysfs/group.c:214 device_add_groups drivers/base/core.c:2473 [inline] device_add_attrs drivers/base/core.c:2621 [inline] device_add+0x81f/0x1ee0 drivers/base/core.c:3345 netdev_register_kobject+0x181/0x430 net/core/net-sysfs.c:2010 register_netdevice+0xd31/0x1500 net/core/dev.c:10336 ppp_unit_register drivers/net/ppp/ppp_generic.c:1196 [inline] ppp_dev_configure+0xb3e/0xec0 drivers/net/ppp/ppp_generic.c:1252 ppp_create_interface drivers/net/ppp/ppp_generic.c:3325 [inline] ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1037 [inline] ppp_ioctl+0x1889/0x2d50 drivers/net/ppp/ppp_generic.c:710 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 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: 0033:0x7f429c30fe99 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:00007f429ac85168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f429c422f60 RCX: 00007f429c30fe99 RDX: 0000000020000680 RSI: 00000000c004743e RDI: 0000000000000003 RBP: 00007f429c369ff1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fffbf5c000f R14: 00007f429ac85300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: 76 7e jbe 0x80 2: 0b 00 or (%rax),%eax 4: 85 ed test %ebp,%ebp 6: 74 4d je 0x55 8: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax f: fc ff df 12: 4d 89 f4 mov %r14,%r12 15: 4c 89 f5 mov %r14,%rbp 18: 49 c1 ec 03 shr $0x3,%r12 1c: 83 e5 07 and $0x7,%ebp 1f: 49 01 c4 add %rax,%r12 22: 83 c5 03 add $0x3,%ebp 25: e8 30 7c 0b 00 callq 0xb7c5a * 2a: f3 90 pause <-- trapping instruction 2c: 41 0f b6 04 24 movzbl (%r12),%eax 31: 40 38 c5 cmp %al,%bpl 34: 7c 08 jl 0x3e 36: 84 c0 test %al,%al 38: 0f 85 33 06 00 00 jne 0x671 3e: 8b .byte 0x8b 3f: 43 rex.XB