rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (1 GPs behind) idle=ff6/1/0x4000000000000002 softirq=10298/10299 fqs=2852 (t=10500 jiffies g=6081 q=124) rcu: rcu_preempt kthread starved for 4784 jiffies! g6081 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 rcu: RCU grace-period kthread stack dump: rcu_preempt R running task 29032 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: 8140 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:__memcg_kmem_uncharge+0x28/0x2e0 mm/memcontrol.c:2910 Code: 00 00 55 48 89 e5 41 57 41 56 41 55 41 54 53 50 89 f3 49 89 fc 48 b8 00 00 00 00 00 fc ff df 4c 8d 77 38 4d 89 f5 49 c1 ed 03 <41> 80 7c 05 00 00 74 08 4c 89 f7 e8 d8 f4 fa ff 4d 8b 3e b8 01 00 RSP: 0018:ffffc90001ec75b8 EFLAGS: 00000a02 ORIG_RAX: ffffffffffffff13 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff88808d65e100 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffea00029c7bc0 RBP: ffffc90001ec75e8 R08: 000000000003a768 R09: ffffed101522d687 R10: ffffed101522d687 R11: 0000000000000000 R12: ffffea00029c7bc0 R13: 1ffffd4000538f7f R14: ffffea00029c7bf8 R15: ffff8880a916b428 memcg_kmem_uncharge include/linux/memcontrol.h:1402 [inline] free_thread_stack+0x12e/0x590 kernel/fork.c:284 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:arch_local_irq_restore arch/x86/include/asm/paravirt.h:752 [inline] RIP: 0010:qlink_free+0x91/0xb0 mm/kasan/quarantine.c:151 Code: 58 07 00 74 35 4c 89 f7 57 9d 0f 1f 44 00 00 e8 15 1b ca ff eb 19 e8 ae 18 ca ff 48 83 3d 0e 7a 58 07 00 74 17 4c 89 f7 57 9d <0f> 1f 44 00 00 5b 41 5e 41 5f 5d c3 0f 0b 0f 0b 0f 0b 0f 0b 90 66 RSP: 0018:ffffc90001ec7848 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: ffff88808d65e994 RBX: ffff888095780000 RCX: ffffffff815c0597 RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000286 RBP: ffffc90001ec7860 R08: ffff88808d65e958 R09: fffffbfff13c851f R10: fffffbfff13c851f R11: 0000000000000000 R12: ffff888095780000 R13: 00000000000000c8 R14: 0000000000000286 R15: ffff8880aa8021c0 qlist_free_all mm/kasan/quarantine.c:167 [inline] quarantine_reduce+0x15e/0x1d0 mm/kasan/quarantine.c:260 __kasan_kmalloc+0x46/0x1b0 mm/kasan/common.c:493 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:520 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc mm/slab.c:3320 [inline] kmem_cache_alloc+0x1f5/0x2e0 mm/slab.c:3484 vm_area_dup kernel/fork.c:359 [inline] dup_mmap+0x587/0xe00 kernel/fork.c:544 dup_mm+0x9e/0x340 kernel/fork.c:1360 copy_mm kernel/fork.c:1416 [inline] copy_process+0x1e49/0x5510 kernel/fork.c:2072 _do_fork+0x13e/0x660 kernel/fork.c:2421 __do_sys_clone kernel/fork.c:2576 [inline] __se_sys_clone kernel/fork.c:2557 [inline] __x64_sys_clone+0x20b/0x250 kernel/fork.c:2557 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458c4a Code: f7 d8 64 89 04 25 d4 02 00 00 64 4c 8b 0c 25 10 00 00 00 31 d2 4d 8d 91 d0 02 00 00 31 f6 bf 11 00 20 01 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 f5 00 00 00 85 c0 41 89 c5 0f 85 fc 00 00 RSP: 002b:00007fff36604810 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007fff36604810 RCX: 0000000000458c4a RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 00007fff36604850 R08: 0000000000000001 R09: 00000000015dd940 R10: 00000000015ddc10 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000000 R15: 00007fff366048a0