rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (1 GPs behind) idle=ba6/1/0x4000000000000002 softirq=13933/13934 fqs=3 (t=10501 jiffies g=7537 q=219) rcu: rcu_preempt kthread starved for 10496 jiffies! g7537 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0 rcu: RCU grace-period kthread stack dump: rcu_preempt I28984 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 1 CPU: 1 PID: 8830 Comm: syz-executor.0 Not tainted 5.5.0-rc5-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:1517 [inline] __hrtimer_run_queues+0x403/0x840 kernel/time/hrtimer.c:1579 hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1641 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:mod_memcg_page_state+0x123/0x190 include/linux/memcontrol.h:653 Code: e8 22 8f 6a 00 48 83 3d b2 fd e1 07 00 74 70 e8 c3 26 2e 00 4c 89 ff 57 9d 0f 1f 44 00 00 e8 44 cf 33 00 eb 43 e8 ad 26 2e 00 3c e8 d6 cc 33 00 48 c7 c0 68 95 2a 89 48 c1 e8 03 42 80 3c 20 RSP: 0018:ffffc900025d7858 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13 RAX: ffffffff814897d3 RBX: 0000000000000000 RCX: ffff88809784a380 RDX: 0000000000000000 RSI: 00000000fffffffc RDI: ffffea00029e9f80 RBP: ffffc900025d7878 R08: 000000000003a728 R09: ffffed101521de99 R10: ffffed101521de99 R11: 0000000000000000 R12: dffffc0000000000 R13: dffffc0000000000 R14: 00000000fffffffc R15: ffff8880a90ef4b8 free_thread_stack+0x168/0x590 kernel/fork.c:280 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_common kernel/sched/core.c:4236 [inline] preempt_schedule+0xdb/0x120 kernel/sched/core.c:4261 ___preempt_schedule+0x16/0x18 arch/x86/entry/thunk_64.S:50 __kunmap_atomic include/linux/highmem.h:102 [inline] clear_highpage include/linux/highmem.h:215 [inline] kernel_init_free_pages mm/page_alloc.c:1125 [inline] prep_new_page+0x161/0x2e0 mm/page_alloc.c:2171 get_page_from_freelist+0x850/0xaa0 mm/page_alloc.c:3695 __alloc_pages_nodemask+0x264/0x5d0 mm/page_alloc.c:4756 __alloc_pages include/linux/gfp.h:496 [inline] __alloc_pages_node include/linux/gfp.h:509 [inline] alloc_pages_vma+0x94a/0xd50 mm/mempolicy.c:2151 do_huge_pmd_anonymous_page+0x883/0xe50 mm/huge_memory.c:758 create_huge_pmd mm/memory.c:3888 [inline] __handle_mm_fault mm/memory.c:4098 [inline] handle_mm_fault+0x2017/0x2890 mm/memory.c:4164 do_user_addr_fault+0x589/0xaf0 arch/x86/mm/fault.c:1441 __do_page_fault+0xd3/0x1f0 arch/x86/mm/fault.c:1506 do_page_fault+0x99/0xb0 arch/x86/mm/fault.c:1530 page_fault+0x39/0x40 arch/x86/entry/entry_64.S:1203 RIP: 0033:0x4005c0 Code: 01 e9 cd 01 00 00 48 8b 44 24 10 48 0b 44 24 28 75 20 48 8b 14 24 48 8b 7c 24 20 be 02 00 00 00 e8 a5 55 00 00 48 8b 4c 24 08 <66> 89 01 e9 a1 01 00 00 48 8b 44 24 08 48 8b 14 24 be 02 00 00 00 RSP: 002b:00007ffeeb261f70 EFLAGS: 00010202 RAX: 0000000000000002 RBX: 000000000075c9a0 RCX: 00000000200008c0 RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000002 RBP: 0000000000760150 R08: 0000000000000000 R09: 0000000000000000 R10: 00007ffeeb262080 R11: 0000000000000246 R12: 000000000075bf20 R13: 0000000000012fd5 R14: 0000000000760158 R15: 000000000075bf2c