rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (10499 ticks this GP) idle=95d/1/0x4000000000000000 softirq=166056/166059 fqs=8 (t=10500 jiffies g=282053 q=177) rcu: rcu_preempt kthread starved for 10483 jiffies! g282053 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:26576 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4969 [inline] __schedule+0xb72/0x1460 kernel/sched/core.c:6250 schedule+0x12b/0x1f0 kernel/sched/core.c:6323 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x1fd/0x770 kernel/rcu/tree.c:1955 rcu_gp_kthread+0xa5/0x350 kernel/rcu/tree.c:2128 kthread+0x468/0x490 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 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: 2840 Comm: syz-executor.2 Not tainted 5.15.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline] RIP: 0010:smp_call_function_single+0x2a2/0x570 kernel/smp.c:758 Code: e6 01 31 ff e8 af cc 0b 00 41 83 e5 01 75 19 e8 94 c8 0b 00 e9 16 01 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 f3 90 <42> 0f b6 04 23 84 c0 75 15 f7 44 24 68 01 00 00 00 0f 84 e9 00 00 RSP: 0018:ffffc90011cffa20 EFLAGS: 00000293 RAX: ffffffff81787c4e RBX: 1ffff9200239ff51 RCX: ffff88809d975700 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90011cffb30 R08: ffffffff81787c11 R09: ffffed10173674c9 R10: ffffed10173674c9 R11: 0000000000000000 R12: dffffc0000000000 R13: 0000000000000001 R14: 0000000000000000 R15: ffffc90011cffa88 FS: 00005555572cc400(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b30723000 CR3: 000000009eb56000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: task_function_call kernel/events/core.c:119 [inline] event_function_call+0x46b/0x6e0 kernel/events/core.c:288 perf_event_release_kernel+0x1ca/0x900 kernel/events/core.c:5105 perf_release+0x37/0x40 kernel/events/core.c:5201 __fput+0x3fc/0x870 fs/file_table.c:280 task_work_run+0x146/0x1c0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x209/0x220 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x2e/0x70 kernel/entry/common.c:300 do_syscall_64+0x53/0xd0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f6a071eb72b Code: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44 RSP: 002b:00007ffccbfedc60 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f6a071eb72b RDX: 0000001b30723094 RSI: ffffffff818ae01f RDI: 0000000000000003 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000001b30720d0c R10: 000000000000093d R11: 0000000000000293 R12: 00007f6a0734cb60 R13: 00007f6a0734cb60 R14: 00007f6a0734bf60 R15: 00000000001ad7dc NMI backtrace for cpu 1 CPU: 1 PID: 2849 Comm: syz-executor.2 Not tainted 5.15.0-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+0x1dc/0x2d8 lib/dump_stack.c:106 nmi_cpu_backtrace+0x45f/0x490 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x16a/0x280 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x22d/0x390 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+0x1e33/0x2bc0 kernel/rcu/tree.c:2597 update_process_times+0x197/0x200 kernel/time/timer.c:1785 tick_sched_handle kernel/time/tick-sched.c:226 [inline] tick_sched_timer+0x27d/0x420 kernel/time/tick-sched.c:1421 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x4cb/0xa60 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3b3/0x1040 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0xf9/0x270 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x3e/0xb0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0010:_compound_head include/linux/page-flags.h:200 [inline] RIP: 0010:virt_to_head_page include/linux/mm.h:897 [inline] RIP: 0010:kmem_cache_free+0x52/0x190 mm/slub.c:3508 Code: 84 29 01 00 00 49 89 c7 4c 89 f7 e8 18 9e 6c ff 49 89 c4 49 c1 ec 06 49 83 e4 c0 48 b9 00 00 00 00 00 ea ff ff 49 8b 44 0c 08 <89> c2 83 e2 01 48 85 d2 0f 85 15 01 00 00 49 01 cc 4c 8b 6c 24 58 RSP: 0018:ffffc90000dc0880 EFLAGS: 00000202 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffea0000000000 RDX: 0000000000000300 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000dc0b48 R08: ffffffff813b8de7 R09: ffffffff88075225 R10: 0000000000000002 R11: ffff888077db5700 R12: 0000000002980340 R13: 0000000000000000 R14: ffff8880a600d8c0 R15: ffff888012156640 kfree_skb_list+0x41/0x70 net/core/skbuff.c:783 __dev_xmit_skb net/core/dev.c:3881 [inline] __dev_queue_xmit+0x2296/0x35c0 net/core/dev.c:4194 mrp_queue_xmit net/802/mrp.c:364 [inline] mrp_join_timer+0x418/0x820 net/802/mrp.c:608 call_timer_fn+0xf6/0x210 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers+0x71a/0x910 kernel/time/timer.c:1734 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1747 __do_softirq+0x392/0x7a3 kernel/softirq.c:558 __irq_exit_rcu+0xec/0x170 kernel/softirq.c:636 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0010:tomoyo_check_acl+0xbd/0x430 security/tomoyo/domain.c:173 Code: 49 39 dc 0f 84 14 02 00 00 0f 1f 40 00 49 8d 6c 24 18 48 89 e8 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 1d 01 00 00 0f b6 6d 00 <31> ff 89 ee e8 1a 42 a9 fd 85 ed 74 16 e8 41 3f a9 fd e9 c6 00 00 RSP: 0018:ffffc90011d5fa00 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff88801a2f6f90 RCX: 0000000000040000 RDX: ffffc9000db8a000 RSI: 0000000000007313 RDI: 0000000000007314 RBP: 0000000000000000 R08: ffffffff83db05c6 R09: ffffffff83dca192 R10: 0000000000000002 R11: ffff888077db5700 R12: ffff888073705c80 R13: dffffc0000000000 R14: ffff88801a2f6f80 R15: 0000000000000000 tomoyo_path_number_perm+0x42f/0x7c0 security/tomoyo/file.c:733 tomoyo_path_mkdir+0xe3/0x120 security/tomoyo/tomoyo.c:166 security_path_mkdir+0xd5/0x160 security/security.c:1141 do_mkdirat+0x1b4/0x530 fs/namei.c:3905 __do_sys_mkdir fs/namei.c:3929 [inline] __se_sys_mkdir fs/namei.c:3927 [inline] __x64_sys_mkdir+0x6a/0x80 fs/namei.c:3927 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f6a07237bf7 Code: 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 53 00 00 00 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:00007f6a047adfa8 EFLAGS: 00000213 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 0000000020000600 RCX: 00007f6a07237bf7 RDX: 0000000000000004 RSI: 00000000000001ff RDI: 00000000200003c0 RBP: 00007f6a047ae040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000213 R12: 0000000020000340 R13: 00000000200003c0 R14: 00007f6a047ae000 R15: 0000000020000640 ---------------- Code disassembly (best guess): 0: e6 01 out %al,$0x1 2: 31 ff xor %edi,%edi 4: e8 af cc 0b 00 callq 0xbccb8 9: 41 83 e5 01 and $0x1,%r13d d: 75 19 jne 0x28 f: e8 94 c8 0b 00 callq 0xbc8a8 14: e9 16 01 00 00 jmpq 0x12f 19: 66 2e 0f 1f 84 00 00 nopw %cs:0x0(%rax,%rax,1) 20: 00 00 00 23: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 28: f3 90 pause * 2a: 42 0f b6 04 23 movzbl (%rbx,%r12,1),%eax <-- trapping instruction 2f: 84 c0 test %al,%al 31: 75 15 jne 0x48 33: f7 44 24 68 01 00 00 testl $0x1,0x68(%rsp) 3a: 00 3b: 0f .byte 0xf 3c: 84 e9 test %ch,%cl