rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (10499 ticks this GP) idle=949/1/0x4000000000000000 softirq=40132/40132 fqs=14 (t=10501 jiffies g=68853 q=34) rcu: rcu_preempt kthread starved for 10473 jiffies! g68853 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:28696 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4965 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6246 schedule+0xd2/0x260 kernel/sched/core.c:6319 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1966 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2139 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: 20604 Comm: syz-executor.1 Not tainted 5.15.0-rc5-next-20211015-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:check_preemption_disabled+0x2/0x170 lib/smp_processor_id.c:13 Code: 1f 44 00 00 e8 6f 16 4e f8 65 48 8b 3c 25 40 70 02 00 e8 41 43 05 f8 eb 99 0f 1f 44 00 00 0f 0b e9 23 ff ff ff cc cc cc 41 56 <41> 55 49 89 f5 41 54 55 48 89 fd 53 0f 1f 44 00 00 65 44 8b 25 cd RSP: 0018:ffffc90000007fe0 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff814d7e51 RDX: 1ffff1101738748c RSI: ffffffff89aa9d20 RDI: ffffffff8a046f60 RBP: ffffc900028c6e68 R08: 0000000000000000 R09: ffff88813fe36007 R10: ffffed1027fc6c00 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f3974b19700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000006eae7000 CR4: 00000000003526f0 Call Trace: irq_exit_rcu+0x11/0x20 kernel/softirq.c:651 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:lock_acquire+0x1ef/0x510 kernel/locking/lockdep.c:5605 Code: ec a5 7e 83 f8 01 0f 85 b4 02 00 00 9c 58 f6 c4 02 0f 85 9f 02 00 00 48 83 7c 24 08 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0018:ffffc900028c6f10 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff92000518de4 RCX: 694c4d7b092c3dbb RDX: 1ffff1100f8174ec RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8ff44a07 R10: fffffbfff1fe8940 R11: 0000000000000000 R12: 0000000000000002 R13: 0000000000000000 R14: ffffffff8bb82ea0 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:268 [inline] rcu_read_lock include/linux/rcupdate.h:694 [inline] filemap_map_pages+0x1b5/0x1630 mm/filemap.c:3296 do_fault_around mm/memory.c:4134 [inline] do_read_fault mm/memory.c:4149 [inline] do_fault mm/memory.c:4284 [inline] handle_pte_fault mm/memory.c:4542 [inline] __handle_mm_fault+0x28c6/0x5120 mm/memory.c:4677 handle_mm_fault+0x1c8/0x790 mm/memory.c:4775 faultin_page mm/gup.c:939 [inline] __get_user_pages+0x522/0xfb0 mm/gup.c:1160 __get_user_pages_locked mm/gup.c:1345 [inline] get_user_pages_unlocked+0x1b3/0x760 mm/gup.c:2204 hva_to_pfn_slow arch/x86/kvm/../../../virt/kvm/kvm_main.c:2277 [inline] hva_to_pfn+0x1bf/0xdd0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2409 __gfn_to_pfn_memslot+0x229/0x420 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2468 kvm_faultin_pfn+0x50c/0xea0 arch/x86/kvm/mmu/mmu.c:3879 direct_page_fault+0x42c/0x25f0 arch/x86/kvm/mmu/mmu.c:3912 kvm_mmu_do_page_fault arch/x86/kvm/mmu.h:201 [inline] kvm_mmu_page_fault+0x27f/0x1940 arch/x86/kvm/mmu/mmu.c:5196 handle_ept_violation+0x29c/0x6e0 arch/x86/kvm/vmx/vmx.c:5352 __vmx_handle_exit arch/x86/kvm/vmx/vmx.c:6061 [inline] vmx_handle_exit+0x4be/0x1950 arch/x86/kvm/vmx/vmx.c:6078 vcpu_enter_guest+0x2abc/0x4440 arch/x86/kvm/x86.c:9720 vcpu_run arch/x86/kvm/x86.c:9787 [inline] kvm_arch_vcpu_ioctl_run+0x47c/0x1b10 arch/x86/kvm/x86.c:10019 kvm_vcpu_ioctl+0x570/0xf30 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3787 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: 0033:0x7f39775a3a39 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:00007f3974b19188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f39776a6f60 RCX: 00007f39775a3a39 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005 RBP: 00007f39775fdc5f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd8c76e31f R14: 00007f3974b19300 R15: 0000000000022000 NMI backtrace for cpu 1 CPU: 1 PID: 20603 Comm: syz-executor.5 Not tainted 5.15.0-rc5-next-20211015-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:604 [inline] check_cpu_stall kernel/rcu/tree_stall.h:688 [inline] rcu_pending kernel/rcu/tree.c:3889 [inline] rcu_sched_clock_irq.cold+0x9d/0x746 kernel/rcu/tree.c:2608 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+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:lock_acquire+0x1ef/0x510 kernel/locking/lockdep.c:5605 Code: ec a5 7e 83 f8 01 0f 85 b4 02 00 00 9c 58 f6 c4 02 0f 85 9f 02 00 00 48 83 7c 24 08 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0018:ffffc900028572a8 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff9200050ae57 RCX: ffffffff815c3adf RDX: 1ffff110114fec2c RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff8ff44a37 R10: fffffbfff1fe8946 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000000 R14: ffff88808b2f7828 R15: 0000000000000000 down_read+0x98/0x440 kernel/locking/rwsem.c:1464 mmap_read_lock include/linux/mmap_lock.h:117 [inline] get_user_pages_unlocked+0xea/0x760 mm/gup.c:2203 hva_to_pfn_slow arch/x86/kvm/../../../virt/kvm/kvm_main.c:2277 [inline] hva_to_pfn+0x1bf/0xdd0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2409 __gfn_to_pfn_memslot+0x229/0x420 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2468 kvm_faultin_pfn+0x50c/0xea0 arch/x86/kvm/mmu/mmu.c:3879 direct_page_fault+0x42c/0x25f0 arch/x86/kvm/mmu/mmu.c:3912 kvm_mmu_do_page_fault arch/x86/kvm/mmu.h:201 [inline] kvm_mmu_page_fault+0x27f/0x1940 arch/x86/kvm/mmu/mmu.c:5196 handle_ept_violation+0x29c/0x6e0 arch/x86/kvm/vmx/vmx.c:5352 __vmx_handle_exit arch/x86/kvm/vmx/vmx.c:6061 [inline] vmx_handle_exit+0x4be/0x1950 arch/x86/kvm/vmx/vmx.c:6078 vcpu_enter_guest+0x2abc/0x4440 arch/x86/kvm/x86.c:9720 vcpu_run arch/x86/kvm/x86.c:9787 [inline] kvm_arch_vcpu_ioctl_run+0x47c/0x1b10 arch/x86/kvm/x86.c:10019 kvm_vcpu_ioctl+0x570/0xf30 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3787 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: 0033:0x7f5cb9ffca39 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:00007f5cb7572188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f5cba0fff60 RCX: 00007f5cb9ffca39 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005 RBP: 00007f5cba056c5f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe81078eaf R14: 00007f5cb7572300 R15: 0000000000022000 sched: RT throttling activated ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 44 00 00 add %r8b,(%rax) 3: e8 6f 16 4e f8 callq 0xf84e1677 8: 65 48 8b 3c 25 40 70 mov %gs:0x27040,%rdi f: 02 00 11: e8 41 43 05 f8 callq 0xf8054357 16: eb 99 jmp 0xffffffb1 18: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 1d: 0f 0b ud2 1f: e9 23 ff ff ff jmpq 0xffffff47 24: cc int3 25: cc int3 26: cc int3 27: 41 56 push %r14 * 29: 41 55 push %r13 <-- trapping instruction 2b: 49 89 f5 mov %rsi,%r13 2e: 41 54 push %r12 30: 55 push %rbp 31: 48 89 fd mov %rdi,%rbp 34: 53 push %rbx 35: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 3a: 65 gs 3b: 44 rex.R 3c: 8b .byte 0x8b 3d: 25 .byte 0x25 3e: cd .byte 0xcd