rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (1 GPs behind) idle=9a6/1/0x4000000000000002 softirq=11307/11309 fqs=34 (t=10500 jiffies g=7189 q=185) rcu: rcu_preempt kthread starved for 10426 jiffies! g7189 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 0x90004000 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: 8372 Comm: syz-executor.4 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+0x12e/0x590 kernel/fork.c:280 Code: bf 00 00 00 00 00 ea ff ff 48 01 c7 be 03 00 00 00 e8 06 a2 60 00 e9 5d 04 00 00 e8 5c 2d 2e 00 48 89 df 31 f6 e8 42 af 6e 00 <43> 80 3c 2e 00 74 08 4c 89 e7 e8 43 a4 69 00 49 8b 1c 24 48 83 c3 RSP: 0018:ffffc90002327078 EFLAGS: 00000292 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000001 RBX: ffffea0002482a80 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffea0002482a80 RBP: ffffc900023270b0 R08: 000000000003a768 R09: ffffed1015092f47 R10: ffffed1015092f47 R11: 0000000000000000 R12: ffff8880a1bbce20 R13: dffffc0000000000 R14: 1ffff110143779c4 R15: ffff8880a8497a28 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_notrace+0xdb/0x120 kernel/sched/core.c:4309 ___preempt_schedule_notrace+0x16/0x27 arch/x86/entry/thunk_64.S:51 rcu_is_watching+0x82/0xa0 kernel/rcu/tree.c:923 kernel_text_address kernel/extable.c:137 [inline] __kernel_text_address+0x74/0x110 kernel/extable.c:104 unwind_get_return_address+0x4c/0x90 arch/x86/kernel/unwind_frame.c:19 arch_stack_walk+0x98/0xe0 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0xb6/0x150 kernel/stacktrace.c:123 save_stack mm/kasan/common.c:71 [inline] set_track mm/kasan/common.c:79 [inline] __kasan_kmalloc+0x11c/0x1b0 mm/kasan/common.c:512 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:520 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc_node mm/slab.c:3263 [inline] kmem_cache_alloc_node+0x235/0x280 mm/slab.c:3575 __alloc_skb+0x9f/0x500 net/core/skbuff.c:197 alloc_skb include/linux/skbuff.h:1049 [inline] nlmsg_new include/net/netlink.h:888 [inline] rtmsg_ifa+0x17d/0x2f0 net/ipv4/devinet.c:1899 __inet_insert_ifa+0x957/0xb60 net/ipv4/devinet.c:551 inet_rtm_newaddr+0x104b/0x1980 net/ipv4/devinet.c:951 rtnetlink_rcv_msg+0x889/0xd40 net/core/rtnetlink.c:5422 netlink_rcv_skb+0x19e/0x3d0 net/netlink/af_netlink.c:2477 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5440 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x767/0x920 net/netlink/af_netlink.c:1328 netlink_sendmsg+0xa21/0xd40 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:639 [inline] sock_sendmsg net/socket.c:659 [inline] __sys_sendto+0x442/0x5e0 net/socket.c:1985 __do_sys_sendto net/socket.c:1997 [inline] __se_sys_sendto net/socket.c:1993 [inline] __x64_sys_sendto+0xe5/0x100 net/socket.c:1993 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x414373 Code: ff 0f 83 b0 19 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 83 3d fd 40 66 00 00 75 17 49 89 ca b8 2c 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 81 19 00 00 c3 48 83 ec 08 e8 87 fa ff ff RSP: 002b:00007ffeba34d1e8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000a72200 RCX: 0000000000414373 RDX: 0000000000000028 RSI: 0000000000a72250 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffeba34d1f0 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000a72250 R15: 0000000000000003