rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-....: (10500 ticks this GP) idle=ec3/1/0x4000000000000000 softirq=78994/78994 fqs=5245 
	(t=10502 jiffies g=120885 q=2272)
NMI backtrace for cpu 1
CPU: 1 PID: 8607 Comm: syz-executor.5 Not tainted 5.16.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x45f/0x490 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x16a/0x280 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x22d/0x390 kernel/rcu/tree_stall.h:343
 print_cpu_stall kernel/rcu/tree_stall.h:627 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:711 [inline]
 rcu_pending kernel/rcu/tree.c:3878 [inline]
 rcu_sched_clock_irq+0x1e33/0x2bc0 kernel/rcu/tree.c:2597
 update_process_times+0x197/0x200 kernel/time/timer.c:1785
 tick_sched_handle kernel/time/tick-sched.c:226 [inline]
 tick_sched_timer+0x27d/0x420 kernel/time/tick-sched.c:1428
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x4cb/0xa60 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x3b3/0x1040 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline]
 __sysvec_apic_timer_interrupt+0xf9/0x270 arch/x86/kernel/apic/apic.c:1103
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: d1 52 fd ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 2e f7 4f f7 48 89 df e8 36 a8 51 f7 e8 81 02 75 f7 fb bf 01 00 00 00 <e8> 96 00 44 f7 65 8b 05 b7 49 ec 75 85 c0 74 02 5b c3 e8 3c 31 ea
RSP: 0018:ffffc90002bff570 EFLAGS: 00000282
RAX: a9ac30704b4a0800 RBX: ffffffff8cc5c4d8 RCX: ffffffff81667321
RDX: dffffc0000000000 RSI: 0000000000000001 RDI: 0000000000000001
RBP: ffffc90002bff7b0 R08: dffffc0000000000 R09: fffffbfff1ff41de
R10: fffffbfff1ff41de R11: 0000000000000000 R12: ffffc90002bff680
R13: dffffc0000000000 R14: ffffffff8cc5c4c0 R15: 0000000000000006
 rwsem_down_write_slowpath+0xcbd/0x1480 kernel/locking/rwsem.c:1127
 __down_write_common kernel/locking/rwsem.c:1268 [inline]
 __down_write kernel/locking/rwsem.c:1277 [inline]
 down_write+0x163/0x170 kernel/locking/rwsem.c:1524
 kernfs_remove_by_name_ns+0x24/0x90 fs/kernfs/dir.c:1540
 kernfs_remove_by_name include/linux/kernfs.h:570 [inline]
 remove_files fs/sysfs/group.c:28 [inline]
 sysfs_remove_group+0xf7/0x280 fs/sysfs/group.c:288
 sysfs_remove_groups+0x5b/0xb0 fs/sysfs/group.c:312
 __kobject_del+0x84/0x310 lib/kobject.c:611
 kobject_del+0x41/0x60 lib/kobject.c:643
 ext4_fill_super+0xe819/0xf360 fs/ext4/super.c:5019
 mount_bdev+0x26c/0x3a0 fs/super.c:1370
 legacy_get_tree+0xea/0x180 fs/fs_context.c:610
 vfs_get_tree+0x86/0x270 fs/super.c:1500
 do_new_mount fs/namespace.c:2988 [inline]
 path_mount+0x1986/0x2c30 fs/namespace.c:3318
 do_mount fs/namespace.c:3331 [inline]
 __do_sys_mount fs/namespace.c:3539 [inline]
 __se_sys_mount+0x308/0x3c0 fs/namespace.c:3516
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fb1d47ad3ca
Code: 48 c7 c2 bc ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 b8 04 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb1d3120f88 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 00007fb1d47ad3ca
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007fb1d3120fe0
RBP: 00007fb1d3121020 R08: 00007fb1d3121020 R09: 0000000020000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000020000000
R13: 0000000020000100 R14: 00007fb1d3120fe0 R15: 00000000200000c0
 </TASK>
----------------
Code disassembly (best guess):
   0:	d1 52 fd             	rcll   -0x3(%rdx)
   3:	ff 90 53 48 89 fb    	callq  *-0x476b7ad(%rax)
   9:	48 83 c7 18          	add    $0x18,%rdi
   d:	48 8b 74 24 08       	mov    0x8(%rsp),%rsi
  12:	e8 2e f7 4f f7       	callq  0xf74ff745
  17:	48 89 df             	mov    %rbx,%rdi
  1a:	e8 36 a8 51 f7       	callq  0xf751a855
  1f:	e8 81 02 75 f7       	callq  0xf77502a5
  24:	fb                   	sti
  25:	bf 01 00 00 00       	mov    $0x1,%edi
* 2a:	e8 96 00 44 f7       	callq  0xf74400c5 <-- trapping instruction
  2f:	65 8b 05 b7 49 ec 75 	mov    %gs:0x75ec49b7(%rip),%eax        # 0x75ec49ed
  36:	85 c0                	test   %eax,%eax
  38:	74 02                	je     0x3c
  3a:	5b                   	pop    %rbx
  3b:	c3                   	retq
  3c:	e8                   	.byte 0xe8
  3d:	3c 31                	cmp    $0x31,%al
  3f:	ea                   	(bad)