rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (10499 ticks this GP) idle=23a/1/0x4000000000000002 softirq=10159/10159 fqs=41 (t=10500 jiffies g=6209 q=293) rcu: rcu_preempt kthread starved for 10415 jiffies! g6209 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 28824 10 2 0x80004000 Call Trace: context_switch kernel/sched/core.c:3385 [inline] __schedule+0x9a0/0xcc0 kernel/sched/core.c:4081 schedule+0x181/0x210 kernel/sched/core.c:4155 schedule_timeout+0x14f/0x240 kernel/time/timer.c:1895 rcu_gp_fqs_loop kernel/rcu/tree.c:1661 [inline] rcu_gp_kthread+0xed8/0x1770 kernel/rcu/tree.c:1821 kthread+0x332/0x350 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 NMI backtrace for cpu 0 CPU: 0 PID: 8134 Comm: syz-executor.0 Not tainted 5.4.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fb/0x318 lib/dump_stack.c:118 nmi_cpu_backtrace+0xaf/0x1a0 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x174/0x290 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x10/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x15a/0x220 kernel/rcu/tree_stall.h:254 print_cpu_stall kernel/rcu/tree_stall.h:455 [inline] check_cpu_stall kernel/rcu/tree_stall.h:529 [inline] rcu_pending kernel/rcu/tree.c:2827 [inline] rcu_sched_clock_irq+0xe25/0x1ad0 kernel/rcu/tree.c:2271 update_process_times+0x12d/0x180 kernel/time/timer.c:1726 tick_sched_handle kernel/time/tick-sched.c:167 [inline] tick_sched_timer+0x263/0x420 kernel/time/tick-sched.c:1310 __run_hrtimer kernel/time/hrtimer.c:1514 [inline] __hrtimer_run_queues+0x403/0x840 kernel/time/hrtimer.c:1576 hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1638 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline] smp_apic_timer_interrupt+0x109/0x280 arch/x86/kernel/apic/apic.c:1135 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:free_thread_stack+0x18b/0x590 kernel/fork.c:284 Code: ff ff e8 28 04 00 00 43 80 3c 2e 00 74 08 4c 89 e7 e8 09 a4 69 00 49 8b 1c 24 48 83 c3 08 48 89 d8 48 c1 e8 03 42 80 3c 28 00 <74> 08 48 89 df e8 eb a3 69 00 48 8b 1b e9 82 ff ff ff e8 de 2c 2e RSP: 0018:ffffc90002477a18 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 1ffff11012863541 RBX: ffff88809431aa08 RCX: 0000000000040000 RDX: ffffc90001f29000 RSI: 000000000003ffff RDI: 0000000000040000 RBP: ffffc90002477a50 R08: 000000000003a768 R09: fffffbfff120248a R10: fffffbfff120248a R11: 0000000000000000 R12: ffff88809431aaa0 R13: dffffc0000000000 R14: 1ffff11012863554 R15: ffff888098ec3a28 release_task_stack kernel/fork.c:440 [inline] put_task_stack+0xa3/0x130 kernel/fork.c:451 finish_task_switch+0x3f1/0x550 kernel/sched/core.c:3256 context_switch kernel/sched/core.c:3388 [inline] __schedule+0x9a8/0xcc0 kernel/sched/core.c:4081 preempt_schedule_irq+0xc1/0x140 kernel/sched/core.c:4338 retint_kernel+0x1b/0x2b RIP: 0010:memset_erms+0x9/0x10 arch/x86/lib/memset_64.S:66 Code: c1 e9 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 aa 4c 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01 RSP: 0018:ffffc90002477c68 EFLAGS: 00010246 ORIG_RAX: ffffffffffffff13 RAX: ffff8880a2d1c800 RBX: ffff8880aa802700 RCX: 0000000000004540 RDX: 0000000000010000 RSI: 0000000000000000 RDI: ffff88806c1cbac0 RBP: ffffc90002477cc0 R08: ffff8880a2d1c898 R09: ffff88806c1c0000 R10: ffffed10155003c1 R11: 0000000000000000 R12: 0000000000412dc0 R13: 0000000000412dc0 R14: ffff8880aa802700 R15: 00000000ffffffff __do_kmalloc_node mm/slab.c:3615 [inline] __kmalloc_node+0x3c/0x60 mm/slab.c:3623 kmalloc_node include/linux/slab.h:579 [inline] kvmalloc_node+0xcc/0x130 mm/util.c:574 kvmalloc include/linux/mm.h:655 [inline] kvzalloc include/linux/mm.h:663 [inline] kvm_alloc_memslots arch/x86/kvm/../../../virt/kvm/kvm_main.c:567 [inline] kvm_create_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:706 [inline] kvm_dev_ioctl_create_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:3519 [inline] kvm_dev_ioctl+0x3c2/0x2110 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3571 do_vfs_ioctl+0x744/0x1730 fs/ioctl.c:47 ksys_ioctl fs/ioctl.c:743 [inline] __do_sys_ioctl fs/ioctl.c:750 [inline] __se_sys_ioctl fs/ioctl.c:748 [inline] __x64_sys_ioctl+0xe3/0x120 fs/ioctl.c:748 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a679 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fc03fb0bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a679 RDX: 0000000000000000 RSI: 000000000000ae01 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc03fb0c6d4 R13: 00000000004c3a43 R14: 00000000004d8f78 R15: 00000000ffffffff