------------[ cut here ]------------
percpu ref (io_ring_ctx_ref_free) <= 0 (-2) after switching to atomic
WARNING: lib/percpu-refcount.c:197 at percpu_ref_switch_to_atomic_rcu+0x3cc/0x480, CPU#0: syz-executor.3/4020
Modules linked in:
CPU: 0 UID: 0 PID: 4020 Comm: syz-executor.3 Tainted: G        W           6.17.0-rc3-next-20250829 #1 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
RIP: 0010:percpu_ref_switch_to_atomic_rcu+0x3cc/0x480
Code: 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 80 3c 01 00 0f 85 9e 00 00 00 49 8b 75 e8 48 c7 c7 80 97 e2 84 e8 75 c5 e9 fe 90 <0f> 0b 90 90 e9 2b ff ff ff e8 f6 de 5f ff e9 9e fe ff ff e8 7c df
RSP: 0018:ffff88806ce08e20 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8139de70
RDX: ffff888016ecd280 RSI: ffffffff8139de7e RDI: 0000000000000001
RBP: 7ffffffffffffffd R08: 0000000000000001 R09: ffffed100d9c4801
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88800ee44300
R13: ffff88800ee44320 R14: 0000000000000002 R15: 0000000000000003
FS:  0000000000000000(0000) GS:ffff8880e55dd000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f702d1d2ff8 CR3: 00000000314d4000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 rcu_core+0x7c8/0x1800
 handle_softirqs+0x1b1/0x770
 __irq_exit_rcu+0xc4/0x100
 irq_exit_rcu+0x9/0x20
 sysvec_apic_timer_interrupt+0x70/0x80
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:__tlb_remove_folio_pages_size.constprop.0+0x66/0x560
Code: 00 00 4c 8b 63 18 31 ff 4c 89 e6 e8 14 ba d3 ff 4d 85 e4 0f 84 99 03 00 00 e8 a6 be d3 ff 48 8d 43 28 48 89 c2 48 89 44 24 08 <48> b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 2a 04
RSP: 0018:ffff88803dcef830 EFLAGS: 00000293
RAX: ffff88803dcefd08 RBX: ffff88803dcefce0 RCX: ffffffff81a028cc
RDX: ffff88803dcefd08 RSI: ffffffff81a028da RDI: 0000000000000007
RBP: 0000000000000000 R08: 0000000000000000 R09: fffff9400018120e
R10: ffffffffffffffff R11: 0000000000000001 R12: ffffffffffffffff
R13: 0000000000000001 R14: ffff88803dcefce0 R15: 8000000030241007
 unmap_page_range+0xe86/0x36d0
 unmap_single_vma.constprop.0+0x153/0x230
 unmap_vmas+0x1d6/0x430
 exit_mmap+0x181/0xaa0
 mmput+0xd5/0x390
 do_exit+0x79d/0x2970
 do_group_exit+0xd3/0x2a0
 __x64_sys_exit_group+0x3e/0x50
 x64_sys_call+0x18c5/0x18d0
 do_syscall_64+0xbf/0x360
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff84662eb19
Code: Unable to access opcode bytes at 0x7ff84662eaef.
RSP: 002b:00007ffe28b51c48 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 000000000000001e RCX: 00007ff84662eb19
RDX: 00007ff8465e172b RSI: ffffffffffffffbc RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000001b2ce27914 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000001 R15: 00007ffe28b51d30
 </TASK>
irq event stamp: 3558
hardirqs last  enabled at (3568): [<ffffffff81541b18>] __up_console_sem+0x78/0x80
hardirqs last disabled at (3577): [<ffffffff81541afd>] __up_console_sem+0x5d/0x80
softirqs last  enabled at (2372): [<ffffffff813bafcc>] handle_softirqs+0x50c/0x770
softirqs last disabled at (2799): [<ffffffff813bb364>] __irq_exit_rcu+0xc4/0x100
---[ end trace 0000000000000000 ]---
percpu_ref_switch_to_atomic_rcu: percpu_ref_switch_to_atomic_rcu(): percpu_ref underflow slab kmalloc-64 start ffff88800ee44300 pointer offset 0 size 64
UDC core: USB Raw Gadget: couldn't find an available UDC or it's busy
misc raw-gadget: fail, usb_gadget_register_driver returned -16
UDC core: USB Raw Gadget: couldn't find an available UDC or it's busy
misc raw-gadget: fail, usb_gadget_register_driver returned -16
UDC core: USB Raw Gadget: couldn't find an available UDC or it's busy
percpu_ref_switch_to_atomic_rcu: percpu_ref_switch_to_atomic_rcu(): percpu_ref underflow slab kmalloc-64 start ffff88800c338780 pointer offset 0 size 64
misc raw-gadget: fail, usb_gadget_register_driver returned -16
loop7: detected capacity change from 0 to 264192
loop4: detected capacity change from 0 to 2
SELinux: security_context_str_to_sid (user_u) failed with errno=-22
loop4: detected capacity change from 0 to 16383
SELinux: security_context_str_to_sid (root) failed with errno=-22
percpu_ref_switch_to_atomic_rcu: percpu_ref_switch_to_atomic_rcu(): percpu_ref underflow slab kmalloc-64 start ffff888009d30400 pointer offset 0 size 64
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	4c 8b 63 18          	mov    0x18(%rbx),%r12
   6:	31 ff                	xor    %edi,%edi
   8:	4c 89 e6             	mov    %r12,%rsi
   b:	e8 14 ba d3 ff       	callq  0xffd3ba24
  10:	4d 85 e4             	test   %r12,%r12
  13:	0f 84 99 03 00 00    	je     0x3b2
  19:	e8 a6 be d3 ff       	callq  0xffd3bec4
  1e:	48 8d 43 28          	lea    0x28(%rbx),%rax
  22:	48 89 c2             	mov    %rax,%rdx
  25:	48 89 44 24 08       	mov    %rax,0x8(%rsp)
* 2a:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax <-- trapping instruction
  31:	fc ff df
  34:	48 c1 ea 03          	shr    $0x3,%rdx
  38:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
  3c:	0f                   	.byte 0xf
  3d:	85 2a                	test   %ebp,(%rdx)
  3f:	04                   	.byte 0x4