rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-....: (10558 ticks this GP) idle=90d/1/0x4000000000000000 softirq=34860/34862 fqs=4773 
	(t=10500 jiffies g=55957 q=446)
NMI backtrace for cpu 1
CPU: 1 PID: 15934 Comm: syz-executor.2 Not tainted 5.15.0-rc3-next-20210927-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+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x25e/0x3f0 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:3882 [inline]
 rcu_sched_clock_irq.cold+0x9d/0x746 kernel/rcu/tree.c:2601
 update_process_times+0x16d/0x200 kernel/time/timer.c:1785
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226
 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1428
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103
 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:lock_is_held_type+0xff/0x140 kernel/locking/lockdep.c:5673
Code: 00 00 b8 ff ff ff ff 65 0f c1 05 3c 11 d0 76 83 f8 01 75 29 9c 58 f6 c4 02 75 3d 48 f7 04 24 00 02 00 00 74 01 fb 48 83 c4 08 <44> 89 e8 5b 5d 41 5c 41 5d 41 5e 41 5f c3 45 31 ed eb b9 0f 0b 48
RSP: 0018:ffffc900067af698 EFLAGS: 00000282
RAX: 0000000000000046 RBX: 0000000000000002 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffffff8b9807a0 R08: 0000000000000000 R09: ffffffff8fd0d9cf
R10: fffffbfff1fa1b39 R11: 0000000000000000 R12: ffff888079abba00
R13: 0000000000000000 R14: 00000000ffffffff R15: ffff888079abc490
 lock_is_held include/linux/lockdep.h:283 [inline]
 ___might_sleep+0x3a/0x2c0 kernel/sched/core.c:9476
 lock_sock_fast+0x49/0x100 net/core/sock.c:3231
 mptcp_subflow_cleanup_rbuf net/mptcp/protocol.c:465 [inline]
 mptcp_cleanup_rbuf net/mptcp/protocol.c:499 [inline]
 mptcp_recvmsg+0xad3/0x27b0 net/mptcp/protocol.c:2069
 inet6_recvmsg+0x11b/0x5e0 net/ipv6/af_inet6.c:659
 sock_recvmsg_nosec net/socket.c:944 [inline]
 ____sys_recvmsg+0x527/0x600 net/socket.c:2626
 ___sys_recvmsg+0x127/0x200 net/socket.c:2670
 do_recvmmsg+0x24d/0x6d0 net/socket.c:2764
 __sys_recvmmsg net/socket.c:2843 [inline]
 __do_sys_recvmmsg net/socket.c:2866 [inline]
 __se_sys_recvmmsg net/socket.c:2859 [inline]
 __x64_sys_recvmmsg+0x20b/0x260 net/socket.c:2859
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f9cbf656709
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007f9cbcb8b188 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f9cbf75b0e0 RCX: 00007f9cbf656709
RDX: 0000000000000002 RSI: 00000000200017c0 RDI: 0000000000000004
RBP: 00007f9cbf6b0cb4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000100 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffec499a21f R14: 00007f9cbcb8b300 R15: 0000000000022000
 </TASK>
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	b8 ff ff ff ff       	mov    $0xffffffff,%eax
   7:	65 0f c1 05 3c 11 d0 	xadd   %eax,%gs:0x76d0113c(%rip)        # 0x76d0114b
   e:	76
   f:	83 f8 01             	cmp    $0x1,%eax
  12:	75 29                	jne    0x3d
  14:	9c                   	pushfq
  15:	58                   	pop    %rax
  16:	f6 c4 02             	test   $0x2,%ah
  19:	75 3d                	jne    0x58
  1b:	48 f7 04 24 00 02 00 	testq  $0x200,(%rsp)
  22:	00
  23:	74 01                	je     0x26
  25:	fb                   	sti
  26:	48 83 c4 08          	add    $0x8,%rsp
* 2a:	44 89 e8             	mov    %r13d,%eax <-- trapping instruction
  2d:	5b                   	pop    %rbx
  2e:	5d                   	pop    %rbp
  2f:	41 5c                	pop    %r12
  31:	41 5d                	pop    %r13
  33:	41 5e                	pop    %r14
  35:	41 5f                	pop    %r15
  37:	c3                   	retq
  38:	45 31 ed             	xor    %r13d,%r13d
  3b:	eb b9                	jmp    0xfffffff6
  3d:	0f 0b                	ud2
  3f:	48                   	rex.W