rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-....: (1 GPs behind) idle=b43/1/0x4000000000000000 softirq=99199/99200 fqs=2 (t=10502 jiffies g=195661 q=18921) rcu: rcu_preempt kthread timer wakeup didn't happen for 213 jiffies! g195661 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=63673 rcu: rcu_preempt kthread starved for 216 jiffies! g195661 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:28688 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4984 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6265 schedule+0xd2/0x260 kernel/sched/core.c:6338 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 17266 Comm: syz-executor.3 Not tainted 5.15.0-next-20211104-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:native_apic_mem_write+0x8/0x10 arch/x86/include/asm/apic.h:110 Code: c7 00 08 15 8f e8 48 58 8b 00 eb b0 66 0f 1f 44 00 00 be 01 00 00 00 e9 36 10 2e 00 cc cc cc cc cc cc 89 ff 89 b7 00 c0 5f ff 0f 1f 80 00 00 00 00 48 b8 00 00 00 00 00 fc ff df 53 89 fb 48 RSP: 0018:ffffc90000dc0fd0 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffffffff8b559a80 RCX: 1ffff110173a4f0c RDX: 1ffffffff16ab350 RSI: 0000000000000000 RDI: 00000000000000b0 RBP: 0000000000000000 R08: ffffffff8f15b058 R09: ffffffff8f15b04f R10: ffffffff8f15b057 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055bf27a6fdc8 CR3: 000000006f32f000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: apic_eoi arch/x86/include/asm/apic.h:399 [inline] ack_APIC_irq arch/x86/include/asm/apic.h:445 [inline] __sysvec_apic_timer_interrupt+0x79/0x530 arch/x86/kernel/apic/apic.c:1101 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:lockdep_enabled kernel/locking/lockdep.c:85 [inline] RIP: 0010:lock_is_held_type+0x14/0x140 kernel/locking/lockdep.c:5673 Code: d6 bb ff 0f 0b 8b 44 24 04 eb bd 66 66 2e 0f 1f 84 00 00 00 00 00 41 57 41 56 41 55 41 bd ff ff ff ff 41 54 55 53 48 83 ec 08 <8b> 0d f2 f6 41 04 85 c9 0f 84 d9 00 00 00 65 8b 05 57 e0 b3 76 85 RSP: 0018:ffffc900227cf690 EFLAGS: 00000286 RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff815cdc31 RDX: 1ffffffff1771906 RSI: 00000000ffffffff RDI: ffffffff8bb839a0 RBP: 1ffff920044f9ede R08: 0000000000000000 R09: ffffffff8d905cd7 R10: fffffbfff1b20b9a R11: 0000000000000000 R12: 0000000000000001 R13: 00000000ffffffff R14: dffffc0000000000 R15: 00007f938e84e000 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 zap_pte_range mm/memory.c:1361 [inline] zap_pmd_range mm/memory.c:1471 [inline] zap_pud_range mm/memory.c:1500 [inline] zap_p4d_range mm/memory.c:1521 [inline] unmap_page_range+0xf0e/0x29f0 mm/memory.c:1542 unmap_single_vma+0x198/0x310 mm/memory.c:1587 unmap_vmas+0x16b/0x2f0 mm/memory.c:1619 exit_mmap+0x1d0/0x630 mm/mmap.c:3171 __mmput+0x122/0x4b0 kernel/fork.c:1164 mmput+0x56/0x60 kernel/fork.c:1185 exit_mm kernel/exit.c:507 [inline] do_exit+0xb27/0x2b40 kernel/exit.c:819 do_group_exit+0x125/0x310 kernel/exit.c:929 get_signal+0x47d/0x2220 kernel/signal.c:2830 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:868 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: 0033:0x7f93902a5ae9 Code: Unable to access opcode bytes at RIP 0x7f93902a5abf. RSP: 002b:00007f938d81b218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f93903b8f68 RCX: 00007f93902a5ae9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f93903b8f68 RBP: 00007f93903b8f60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f93903b8f6c R13: 00007ffcd38a3e5f R14: 00007f938d81b300 R15: 0000000000022000 NMI backtrace for cpu 0 CPU: 0 PID: 2405 Comm: syz-executor.5 Not tainted 5.15.0-next-20211104-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: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: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:check_kcov_mode+0x7/0x40 kernel/kcov.c:166 Code: 00 e9 59 fe ff ff 48 8b 7c 24 08 e8 83 c5 46 00 e9 61 fd ff ff cc cc cc cc cc cc cc cc cc cc cc cc cc cc 65 8b 05 59 a9 8a 7e <89> c2 81 e2 00 01 00 00 a9 00 01 ff 00 74 10 31 c0 85 d2 74 15 8b RSP: 0018:ffffc900053ef798 EFLAGS: 00000246 RAX: 0000000080000001 RBX: 00fff00000000002 RCX: 00fff00000000002 RDX: ffff88815ef6ba80 RSI: ffff88815ef6ba80 RDI: 0000000000000003 RBP: ffffea0000b0e400 R08: ffffffffffffffff R09: 0000000000000000 R10: ffffffff81aca827 R11: 0000000000000000 R12: ffffea0000b0e408 R13: ffff888175f4d228 R14: dffffc0000000000 R15: 00007f2c80846000 write_comp_data kernel/kcov.c:221 [inline] __sanitizer_cov_trace_const_cmp8+0x1d/0x70 kernel/kcov.c:294 PageSwapBacked include/linux/page-flags.h:446 [inline] mm_counter_file include/linux/mm.h:2068 [inline] mm_counter include/linux/mm.h:2077 [inline] zap_pte_range mm/memory.c:1360 [inline] zap_pmd_range mm/memory.c:1471 [inline] zap_pud_range mm/memory.c:1500 [inline] zap_p4d_range mm/memory.c:1521 [inline] unmap_page_range+0xe47/0x29f0 mm/memory.c:1542 unmap_single_vma+0x198/0x310 mm/memory.c:1587 unmap_vmas+0x16b/0x2f0 mm/memory.c:1619 exit_mmap+0x1d0/0x630 mm/mmap.c:3171 __mmput+0x122/0x4b0 kernel/fork.c:1164 mmput+0x56/0x60 kernel/fork.c:1185 exit_mm kernel/exit.c:507 [inline] do_exit+0xb27/0x2b40 kernel/exit.c:819 do_group_exit+0x125/0x310 kernel/exit.c:929 get_signal+0x47d/0x2220 kernel/signal.c:2830 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:868 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: 0033:0x7f2c8191aae9 Code: Unable to access opcode bytes at RIP 0x7f2c8191aabf. RSP: 002b:00007f2c7ee90218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f2c81a2df68 RCX: 00007f2c8191aae9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f2c81a2df68 RBP: 00007f2c81a2df60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f2c81a2df6c R13: 00007fff98cab1cf R14: 00007f2c7ee90300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: c7 00 08 15 8f e8 movl $0xe88f1508,(%rax) 6: 48 58 rex.W pop %rax 8: 8b 00 mov (%rax),%eax a: eb b0 jmp 0xffffffbc c: 66 0f 1f 44 00 00 nopw 0x0(%rax,%rax,1) 12: be 01 00 00 00 mov $0x1,%esi 17: e9 36 10 2e 00 jmpq 0x2e1052 1c: cc int3 1d: cc int3 1e: cc int3 1f: cc int3 20: cc int3 21: cc int3 22: 89 ff mov %edi,%edi 24: 89 b7 00 c0 5f ff mov %esi,-0xa04000(%rdi) * 2a: c3 retq <-- trapping instruction 2b: 0f 1f 80 00 00 00 00 nopl 0x0(%rax) 32: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 39: fc ff df 3c: 53 push %rbx 3d: 89 fb mov %edi,%ebx 3f: 48 rex.W