------------[ cut here ]------------
WARNING: kernel/rcu/tree_stall.h:1049 at rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1049, CPU#1: syz.4.1233/12493
Modules linked in:
CPU: 1 UID: 0 PID: 12493 Comm: syz.4.1233 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1049
Code: ff ff 48 c7 c7 a0 35 af 99 be 04 00 00 00 e8 83 35 80 00 4c 89 f7 b8 01 00 00 00 87 05 95 07 07 18 85 c0 0f 85 17 ff ff ff 90 <0f> 0b 90 48 81 ff c0 46 14 8e 74 47 48 c7 c0 a0 5f a2 8f 48 c1 e8
RSP: 0018:ffffc90000a08b78 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000a06 RCX: ffffffff81a82dfd
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8e1446c0
RBP: ffffc90000a08e30 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff335e6b4 R12: 0000000000002904
R13: 1ffff110170e7762 R14: ffffffff8e1446c0 R15: dffffc0000000000
FS:  00007f8031d6b6c0(0000) GS:ffff888125d25000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f65da72b345 CR3: 0000000056a30000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 rcu_core+0x6a9/0x1870 kernel/rcu/tree.c:2852
 handle_softirqs+0x27d/0x850 kernel/softirq.c:626
 __do_softirq kernel/softirq.c:660 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:727
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:743
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__raw_callee_save___pv_queued_spin_unlock+0x10/0x18
Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 52 b8 01 00 00 00 31 d2 f0 0f b0 17 <75> 06 5a c3 cc cc cc cc 56 0f b6 f0 e8 9f ff ff ff 5e 5a c3 cc cc
RSP: 0018:ffffc90003077788 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffff88807b038c88 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88807b038c88
RBP: 1ffff1100f607192 R08: ffff88807b038c8b R09: 1ffff1100f607191
R10: dffffc0000000000 R11: ffffed100f607192 R12: dffffc0000000000
R13: 1ffff1100f607193 R14: ffff88807b038c98 R15: ffff88807b038c90
 pv_queued_spin_unlock arch/x86/include/asm/paravirt.h:561 [inline]
 queued_spin_unlock arch/x86/include/asm/qspinlock.h:57 [inline]
 do_raw_spin_unlock+0x122/0x240 kernel/locking/spinlock_debug.c:142
 __raw_spin_unlock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_unlock+0x1e/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:391 [inline]
 wait_for_commit+0x381/0x440 fs/btrfs/transaction.c:942
 btrfs_commit_transaction+0x64c/0x3bd0 fs/btrfs/transaction.c:2306
 btrfs_quota_enable+0x10ae/0x2920 fs/btrfs/qgroup.c:1222
 btrfs_ioctl_quota_ctl+0x183/0x1c0 fs/btrfs/ioctl.c:3613
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8030f8f749
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8031d6b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f80311e6270 RCX: 00007f8030f8f749
RDX: 0000200000000200 RSI: 00000000c0109428 RDI: 0000000000000005
RBP: 00007f8031013f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f80311e6308 R14: 00007f80311e6270 R15: 00007ffd15771758
 </TASK>
----------------
Code disassembly (best guess):
   0:	90                   	nop
   1:	90                   	nop
   2:	90                   	nop
   3:	90                   	nop
   4:	90                   	nop
   5:	90                   	nop
   6:	90                   	nop
   7:	90                   	nop
   8:	90                   	nop
   9:	90                   	nop
   a:	90                   	nop
   b:	90                   	nop
   c:	90                   	nop
   d:	90                   	nop
   e:	90                   	nop
   f:	90                   	nop
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
  16:	90                   	nop
  17:	90                   	nop
  18:	90                   	nop
  19:	90                   	nop
  1a:	f3 0f 1e fa          	endbr64
  1e:	52                   	push   %rdx
  1f:	b8 01 00 00 00       	mov    $0x1,%eax
  24:	31 d2                	xor    %edx,%edx
  26:	f0 0f b0 17          	lock cmpxchg %dl,(%rdi)
* 2a:	75 06                	jne    0x32 <-- trapping instruction
  2c:	5a                   	pop    %rdx
  2d:	c3                   	ret
  2e:	cc                   	int3
  2f:	cc                   	int3
  30:	cc                   	int3
  31:	cc                   	int3
  32:	56                   	push   %rsi
  33:	0f b6 f0             	movzbl %al,%esi
  36:	e8 9f ff ff ff       	call   0xffffffda
  3b:	5e                   	pop    %rsi
  3c:	5a                   	pop    %rdx
  3d:	c3                   	ret
  3e:	cc                   	int3
  3f:	cc                   	int3