INFO: rcu_preempt self-detected stall on CPU 1-...: (10499 ticks this GP) idle=ace/140000000000002/0 softirq=93257/93257 fqs=30 (t=10500 jiffies g=27095 c=27094 q=407) rcu_preempt kthread starved for 10422 jiffies! g27095 c27094 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=0 rcu_preempt R running task 29920 8 2 0x80000000 Call Trace: schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_timeout+0x43c/0xe40 kernel/time/timer.c:1746 rcu_gp_kthread+0xb8e/0x1ce0 kernel/rcu/tree.c:2255 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 NMI backtrace for cpu 1 CPU: 1 PID: 11397 Comm: syz-executor.5 Not tainted 4.14.175-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x13e/0x194 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x139/0x17e lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:158 [inline] rcu_dump_cpu_stacks+0x16d/0x1b8 kernel/rcu/tree.c:1396 print_cpu_stall kernel/rcu/tree.c:1542 [inline] check_cpu_stall kernel/rcu/tree.c:1610 [inline] __rcu_pending kernel/rcu/tree.c:3390 [inline] rcu_pending kernel/rcu/tree.c:3452 [inline] rcu_check_callbacks.cold+0x490/0xdaa kernel/rcu/tree.c:2792 update_process_times+0x29/0x60 kernel/time/timer.c:1590 tick_sched_handle+0x7d/0x150 kernel/time/tick-sched.c:165 tick_sched_timer+0x3e/0x120 kernel/time/tick-sched.c:1223 __run_hrtimer kernel/time/hrtimer.c:1223 [inline] __hrtimer_run_queues+0x25c/0xbb0 kernel/time/hrtimer.c:1287 hrtimer_interrupt+0x1e6/0x5e0 kernel/time/hrtimer.c:1321 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1075 [inline] smp_apic_timer_interrupt+0x117/0x5e0 arch/x86/kernel/apic/apic.c:1100 apic_timer_interrupt+0x8f/0xa0 arch/x86/entry/entry_64.S:792 RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:46 [inline] RIP: 0010:stack_access_ok+0x93/0x130 arch/x86/kernel/unwind_orc.c:279 RSP: 0018:ffff8880aeb07378 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff10 RAX: ffff88805f910000 RBX: ffff88805f908000 RCX: 1ffff11015d60e99 RDX: ffff88805f90ff58 RSI: ffff88805f90ff50 RDI: ffff8880aeb074c8 RBP: ffff88805f90ff50 R08: ffffffff88e584e4 R09: ffff88805f90ff00 R10: ffff8880aeb074ed R11: 0000000000058071 R12: ffff8880aeb074b8 R13: dffffc0000000000 R14: ffff8880aeb07500 R15: 0000000000000001 deref_stack_reg+0x56/0xc0 arch/x86/kernel/unwind_orc.c:289 unwind_next_frame+0xa06/0x17a0 arch/x86/kernel/unwind_orc.c:425 __save_stack_trace+0x6b/0xd0 arch/x86/kernel/stacktrace.c:44 save_stack+0x32/0xa0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc mm/kasan/kasan.c:551 [inline] kasan_kmalloc+0xbf/0xe0 mm/kasan/kasan.c:529 kmem_cache_alloc+0x127/0x770 mm/slab.c:3552 kmem_cache_zalloc include/linux/slab.h:651 [inline] fill_pool lib/debugobjects.c:110 [inline] __debug_object_init+0x5b7/0x830 lib/debugobjects.c:341 debug_object_init lib/debugobjects.c:393 [inline] debug_object_activate+0x274/0x450 lib/debugobjects.c:474 debug_rcu_head_queue kernel/rcu/rcu.h:152 [inline] __call_rcu.constprop.0+0x31/0x7e0 kernel/rcu/tree.c:3050 sctp_bind_addr_clean+0x113/0x1e0 net/sctp/bind_addr.c:140 sctp_association_free+0x278/0x765 net/sctp/associola.c:375 sctp_cmd_delete_tcb net/sctp/sm_sideeffect.c:924 [inline] sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1312 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1179 [inline] sctp_do_sm+0x3557/0x4a90 net/sctp/sm_sideeffect.c:1150 sctp_generate_heartbeat_event+0x1da/0x3f0 net/sctp/sm_sideeffect.c:391 call_timer_fn+0x14a/0x650 kernel/time/timer.c:1279 expire_timers kernel/time/timer.c:1318 [inline] __run_timers kernel/time/timer.c:1636 [inline] __run_timers kernel/time/timer.c:1604 [inline] run_timer_softirq+0x52a/0x1390 kernel/time/timer.c:1649 __do_softirq+0x254/0x9bf kernel/softirq.c:288 invoke_softirq kernel/softirq.c:368 [inline] irq_exit+0x15b/0x1a0 kernel/softirq.c:409 exiting_irq arch/x86/include/asm/apic.h:648 [inline] smp_apic_timer_interrupt+0x141/0x5e0 arch/x86/kernel/apic/apic.c:1102 apic_timer_interrupt+0x8f/0xa0 arch/x86/entry/entry_64.S:792 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:779 [inline] RIP: 0010:slab_alloc mm/slab.c:3383 [inline] RIP: 0010:kmem_cache_alloc+0x28e/0x770 mm/slab.c:3550 RSP: 0018:ffff88805f90f930 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff10 RAX: 0000000000000007 RBX: 0000000001080020 RCX: 1ffff11012ed2553 RDX: 0000000000000000 RSI: ffff888097692a78 RDI: 0000000000000282 RBP: ffff8880a6154d80 R08: 0000000000001ee1 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880a6154d80 R13: 0000000001080020 R14: 0000000000000282 R15: ffff888064c478c0 ext4_es_alloc_extent fs/ext4/extents_status.c:334 [inline] __es_insert_extent+0x241/0xe20 fs/ext4/extents_status.c:673 ext4_es_insert_extent+0x1b9/0x530 fs/ext4/extents_status.c:727 ext4_map_blocks+0x9f6/0x1610 fs/ext4/inode.c:715 ext4_getblk+0x98/0x3f0 fs/ext4/inode.c:980 ext4_bread+0x6c/0x1a0 fs/ext4/inode.c:1030 ext4_append+0x143/0x350 fs/ext4/namei.c:65 ext4_init_new_dir fs/ext4/namei.c:2628 [inline] ext4_mkdir+0x4c9/0xb60 fs/ext4/namei.c:2675 vfs_mkdir+0x3af/0x620 fs/namei.c:3849 SYSC_mkdirat fs/namei.c:3872 [inline] SyS_mkdirat fs/namei.c:3856 [inline] SYSC_mkdir fs/namei.c:3883 [inline] SyS_mkdir+0x1bc/0x210 fs/namei.c:3881 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45c849 RSP: 002b:00007fcc578bdc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007fcc578be6d4 RCX: 000000000045c849 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200000c0 RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000072c R14: 00000000004c230d R15: 000000000076bf0c