XFS (loop0): Invalid superblock magic number INFO: rcu_preempt self-detected stall on CPU 1-...: (1 GPs behind) idle=f96/140000000000002/0 softirq=15427/15429 fqs=2 (t=10500 jiffies g=2683 c=2682 q=477) rcu_preempt kthread starved for 10496 jiffies! g2683 c2682 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: 8780 Comm: syz-executor.4 Not tainted 4.14.172-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:constant_test_bit arch/x86/include/asm/bitops.h:325 [inline] RIP: 0010:netif_tx_queue_stopped include/linux/netdevice.h:2912 [inline] RIP: 0010:dev_hard_start_xmit+0x282/0x890 net/core/dev.c:3032 RSP: 0018:ffff8880aeb07140 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10 RAX: 1ffff11010df49c1 RBX: ffff88809659a040 RCX: 0000000000000000 RDX: 0000000000000100 RSI: ffffffff87d84360 RDI: ffff888086fa4e08 RBP: dffffc0000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffff8880a7e24980 R14: ffff888086fa4d40 R15: 0000000000000001 __dev_queue_xmit+0x1d91/0x25c0 net/core/dev.c:3525 neigh_hh_output include/net/neighbour.h:490 [inline] neigh_output include/net/neighbour.h:498 [inline] ip_finish_output2+0xde8/0x14a0 net/ipv4/ip_output.c:229 ip_finish_output+0x556/0xc30 net/ipv4/ip_output.c:317 NF_HOOK_COND include/linux/netfilter.h:239 [inline] ip_output+0x1c2/0x520 net/ipv4/ip_output.c:405 dst_output include/net/dst.h:462 [inline] ip_local_out+0x93/0x170 net/ipv4/ip_output.c:124 iptunnel_xmit+0x583/0x970 net/ipv4/ip_tunnel_core.c:91 geneve_xmit_skb drivers/net/geneve.c:854 [inline] geneve_xmit+0xcfc/0x26b0 drivers/net/geneve.c:930 __netdev_start_xmit include/linux/netdevice.h:4039 [inline] netdev_start_xmit include/linux/netdevice.h:4048 [inline] xmit_one net/core/dev.c:3009 [inline] dev_hard_start_xmit+0x186/0x890 net/core/dev.c:3025 __dev_queue_xmit+0x1d91/0x25c0 net/core/dev.c:3525 neigh_hh_output include/net/neighbour.h:490 [inline] neigh_output include/net/neighbour.h:498 [inline] ip6_finish_output2+0x1085/0x2150 net/ipv6/ip6_output.c:120 ip6_finish_output+0x4d9/0xaf0 net/ipv6/ip6_output.c:154 NF_HOOK_COND include/linux/netfilter.h:239 [inline] ip6_output+0x1c9/0x650 net/ipv6/ip6_output.c:171 dst_output include/net/dst.h:462 [inline] NF_HOOK include/linux/netfilter.h:250 [inline] ndisc_send_skb+0xb56/0x11e0 net/ipv6/ndisc.c:483 ndisc_send_rs+0x125/0x630 net/ipv6/ndisc.c:677 addrconf_rs_timer+0x289/0x5a0 net/ipv6/addrconf.c:3757 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:lock_acquire+0x1ec/0x3f0 kernel/locking/lockdep.c:3997 RSP: 0018:ffff888057687890 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff10 RAX: 1ffffffff0fa2ce1 RBX: ffff88807fd98580 RCX: 00000000dde063f6 RDX: dffffc0000000000 RSI: ffff88807fd98e78 RDI: 0000000000000286 RBP: ffff88808007b340 R08: 00000000000003dd R09: ffffffff8a05d7a8 R10: ffff88807fd98e78 R11: ffff88807fd98580 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:152 spin_lock include/linux/spinlock.h:317 [inline] inode_doinit_with_dentry+0x2a2/0xe30 security/selinux/hooks.c:1532 selinux_d_instantiate+0x23/0x30 security/selinux/hooks.c:5917 security_d_instantiate+0x54/0xd0 security/security.c:1261 d_add+0x39/0x630 fs/dcache.c:2650 proc_setup_thread_self+0x282/0x38a fs/proc/thread_self.c:53 proc_fill_super+0x242/0x2cb fs/proc/inode.c:517 mount_ns+0xdc/0x180 fs/super.c:1051 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x3c0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] kern_mount_data+0x51/0xb0 fs/namespace.c:3329 pid_ns_prepare_proc+0x1a/0x80 fs/proc/root.c:222 alloc_pid+0x9be/0xc40 kernel/pid.c:324 copy_process.part.0+0x272f/0x6a70 kernel/fork.c:1785 copy_process kernel/fork.c:1586 [inline] _do_fork+0x180/0xc80 kernel/fork.c:2070 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45c479 RSP: 002b:00007f4f9959ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007f4f9959f6d4 RCX: 000000000045c479 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000030020100 RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000074 R14: 00000000004c2d06 R15: 000000000076bf2c INFO: rcu_sched detected stalls on CPUs/tasks: 1-...: (1 GPs behind) idle=f96/140000000000000/0 softirq=15428/15429 fqs=2 (detected by 0, t=10572 jiffies, g=1961, c=1960, q=14) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 2285 Comm: kworker/u4:3 Not tainted 4.14.172-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfn (flush-8:0) task: ffff8880a3b1c480 task.stack: ffff8880a3b28000 RIP: 0010:__read_once_size include/linux/compiler.h:183 [inline] RIP: 0010:csd_lock_wait kernel/smp.c:108 [inline] RIP: 0010:smp_call_function_single+0xfd/0x370 kernel/smp.c:302 RSP: 0018:ffff8880a3b2ef40 EFLAGS: 00000297 RAX: ffff8880a3b1c480 RBX: 1ffff11014765dec RCX: 0000000000000830 RDX: 0000000000000000 RSI: 00000000000000fb RDI: 0000000000000830 RBP: ffff8880a3b2efe8 R08: 00000000000077c1 R09: ffffffff8a0976c8 R10: ffff8880a3b1cdc8 R11: ffff8880a3b1c480 R12: 0000000000000000 R13: ffff8880a3b2f0a8 R14: 0000000000000001 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000413720 CR3: 0000000091dbf000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: smp_call_function_many+0x61d/0x7a0 kernel/smp.c:434 flush_tlb_others arch/x86/include/asm/paravirt.h:309 [inline] flush_tlb_mm_range+0x1c5/0x300 arch/x86/mm/tlb.c:709 flush_tlb_page arch/x86/include/asm/tlbflush.h:573 [inline] ptep_clear_flush+0xd6/0x100 mm/pgtable-generic.c:87 page_mkclean_one+0x237/0x550 mm/rmap.c:915 rmap_walk_file+0x37c/0x8a0 mm/rmap.c:1829 rmap_walk+0xe5/0x180 mm/rmap.c:1847 page_mkclean+0x148/0x180 mm/rmap.c:981 clear_page_dirty_for_io+0x1f9/0x7e0 mm/page-writeback.c:2704 mpage_submit_page+0x6e/0x220 fs/ext4/inode.c:2202 mpage_process_page_bufs+0x425/0x520 fs/ext4/inode.c:2332 mpage_prepare_extent_to_map+0x43e/0xa50 fs/ext4/inode.c:2704 ext4_writepages+0x105f/0x2fd0 fs/ext4/inode.c:2851 do_writepages+0xd0/0x250 mm/page-writeback.c:2361 __writeback_single_inode+0xda/0x1140 fs/fs-writeback.c:1367 writeback_sb_inodes+0x475/0xcf0 fs/fs-writeback.c:1631 __writeback_inodes_wb+0xbc/0x200 fs/fs-writeback.c:1700 wb_writeback+0x735/0xba0 fs/fs-writeback.c:1809 wb_check_old_data_flush fs/fs-writeback.c:1922 [inline] wb_do_writeback fs/fs-writeback.c:1946 [inline] wb_workfn+0x8a6/0xe60 fs/fs-writeback.c:1975 process_one_work+0x813/0x1540 kernel/workqueue.c:2114 worker_thread+0x5d1/0x1070 kernel/workqueue.c:2248 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Code: d2 08 00 48 8b 54 24 10 4c 89 e9 8b 7c 24 1c 48 8d 74 24 40 e8 f5 fa ff ff 41 89 c4 8b 44 24 58 a8 01 74 10 e8 45 d2 08 00 f3 90 <8b> 54 24 58 83 e2 01 75 f0 e8 35 d2 08 00 e8 30 d2 08 00 bf 01 rcu_sched kthread starved for 10568 jiffies! g1961 c1960 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=0 rcu_sched R running task 29984 9 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