rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (1 GPs behind) idle=6f3/1/0x4000000000000000 softirq=275988/275990 fqs=0 (t=10500 jiffies g=526565 q=967) rcu: rcu_preempt kthread timer wakeup didn't happen for 10499 jiffies! g526565 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=259591 rcu: rcu_preempt kthread starved for 10500 jiffies! g526565 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:28472 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0xb44/0x5960 kernel/sched/core.c:6287 schedule+0xd3/0x270 kernel/sched/core.c:6366 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x800 kernel/rcu/tree.c:1957 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2130 kthread+0x3e5/0x4d0 kernel/kthread.c:319 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 1171 Comm: syz-executor.0 Not tainted 5.15.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:queued_write_lock_slowpath+0x12c/0x2c0 kernel/locking/qrwlock.c:78 Code: 49 c1 ef 03 41 83 e6 07 48 b8 00 00 00 00 00 fc ff df 49 01 c7 41 83 c6 03 41 0f b6 07 41 38 c6 7c 08 84 c0 0f 85 3e 01 00 00 <8b> 03 3d 00 01 00 00 74 19 f3 90 41 0f b6 07 41 38 c6 7c ec 84 c0 RSP: 0018:ffffc9002033fa38 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffffffff8b60a080 RCX: ffffffff815bf3bf RDX: fffffbfff16c1411 RSI: 0000000000000004 RDI: ffffffff8b60a080 RBP: 1ffff92004067f48 R08: 0000000000000001 R09: ffffffff8b60a083 R10: fffffbfff16c1410 R11: 0000000000000000 R12: ffffffff8b60a084 R13: 00000000000000ff R14: 0000000000000003 R15: fffffbfff16c1410 FS: 0000555556407400(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f16eb4f5718 CR3: 000000014b6ee000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: queued_write_lock include/asm-generic/qrwlock.h:97 [inline] do_raw_write_lock+0x1ce/0x280 kernel/locking/spinlock_debug.c:210 copy_process+0x36c0/0x7590 kernel/fork.c:2313 kernel_clone+0xe7/0xac0 kernel/fork.c:2584 __do_sys_clone+0xc8/0x110 kernel/fork.c:2701 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: 0033:0x7f16ee004f11 Code: 48 85 ff 74 3d 48 85 f6 74 38 48 83 ee 10 48 89 4e 08 48 89 3e 48 89 d7 4c 89 c2 4d 89 c8 4c 8b 54 24 08 b8 38 00 00 00 0f 05 <48> 85 c0 7c 13 74 01 c3 31 ed 58 5f ff d0 48 89 c7 b8 3c 00 00 00 RSP: 002b:00007ffc52f22888 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007f16eb4f5700 RCX: 00007f16ee004f11 RDX: 00007f16eb4f59d0 RSI: 00007f16eb4f52f0 RDI: 00000000003d0f00 RBP: 00007ffc52f22ac0 R08: 00007f16eb4f5700 R09: 00007f16eb4f5700 R10: 00007f16eb4f59d0 R11: 0000000000000206 R12: 00007ffc52f2293e R13: 00007ffc52f2293f R14: 00007f16eb4f5300 R15: 0000000000022000 NMI backtrace for cpu 0 CPU: 0 PID: 1063 Comm: syz-executor.1 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+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_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:3880 [inline] rcu_sched_clock_irq.cold+0x9d/0x746 kernel/rcu/tree.c:2599 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+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:161 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x38/0x70 kernel/locking/spinlock.c:194 Code: 74 24 10 e8 1a ac 21 f8 48 89 ef e8 62 22 22 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 23 0e 15 f8 65 8b 05 ac 2b c8 76 85 c0 74 0a 5b 5d c3 e8 50 89 RSP: 0018:ffffc90000007c08 EFLAGS: 00000206 RAX: 0000000000000002 RBX: 0000000000000200 RCX: 1ffffffff1fab822 RDX: 0000000000000000 RSI: 0000000000000102 RDI: 0000000000000001 RBP: ffff8880b9c20240 R08: 0000000000000001 R09: ffffffff8fd06ac7 R10: 0000000000000001 R11: 0000000000000000 R12: 000000010004d81f R13: ffff8880b9c20240 R14: 0000000000000000 R15: 00000000ffffffff __mod_timer+0x837/0xe30 kernel/time/timer.c:1065 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:636 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648 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:mm_update_next_owner+0x432/0x7a0 kernel/exit.c:388 Code: 8d ad 80 fb ff ff 48 81 fd c0 ca 6b 8b 0f 84 65 01 00 00 e8 e0 f7 30 00 48 8d bd ac fb ff ff 48 89 f8 48 c1 e8 03 0f b6 14 18 <48> 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 b5 02 00 00 44 RSP: 0018:ffffc9001fc6fb40 EFLAGS: 00000a07 RAX: 1ffff11012e1d84d RBX: dffffc0000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff81452bc0 RDI: ffff8880970ec26c RBP: ffff8880970ec6c0 R08: 0000000000000000 R09: ffffffff8b60a083 R10: ffffffff81452bff R11: 0000000000000000 R12: ffff8880262b5880 R13: ffff8880970ec240 R14: 0000000000200000 R15: ffff8880188d2e10 exit_mm kernel/exit.c:500 [inline] do_exit+0xab4/0x2a30 kernel/exit.c:812 do_group_exit+0x125/0x310 kernel/exit.c:922 get_signal+0x47f/0x21d0 kernel/signal.c:2855 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:865 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f1b87882ae9 Code: Unable to access opcode bytes at RIP 0x7f1b87882abf. RSP: 002b:00007f1b84df8218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000000 RBX: 00007f1b87995f68 RCX: 00007f1b87882ae9 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f1b87995f6c RBP: 00007f1b87995f60 R08: 000000000000000e R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f1b87995f6c R13: 00007ffc280a895f R14: 00007f1b84df8300 R15: 0000000000022000 Sending NMI from CPU 0 to CPUs 1: ---------------- Code disassembly (best guess): 0: 49 c1 ef 03 shr $0x3,%r15 4: 41 83 e6 07 and $0x7,%r14d 8: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax f: fc ff df 12: 49 01 c7 add %rax,%r15 15: 41 83 c6 03 add $0x3,%r14d 19: 41 0f b6 07 movzbl (%r15),%eax 1d: 41 38 c6 cmp %al,%r14b 20: 7c 08 jl 0x2a 22: 84 c0 test %al,%al 24: 0f 85 3e 01 00 00 jne 0x168 * 2a: 8b 03 mov (%rbx),%eax <-- trapping instruction 2c: 3d 00 01 00 00 cmp $0x100,%eax 31: 74 19 je 0x4c 33: f3 90 pause 35: 41 0f b6 07 movzbl (%r15),%eax 39: 41 38 c6 cmp %al,%r14b 3c: 7c ec jl 0x2a 3e: 84 c0 test %al,%al