------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 3 PID: 33 at lib/refcount.c:28 refcount_warn_saturate+0x14a/0x210 lib/refcount.c:28
Modules linked in:
CPU: 3 UID: 0 PID: 33 Comm: migration/3 Not tainted 6.13.0-rc6-syzkaller-00006-g5428dc1906dd #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Stopper: active_load_balance_cpu_stop+0x0/0xde0 kernel/sched/fair.c:4221 <- sched_balance_rq+0x20c4/0x2ec0
RIP: 0010:refcount_warn_saturate+0x14a/0x210 lib/refcount.c:28
Code: ff 89 de e8 28 f4 f9 fc 84 db 0f 85 66 ff ff ff e8 7b f9 f9 fc c6 05 4b cb a7 0b 01 90 48 c7 c7 20 9a d1 8b e8 37 30 ba fc 90 <0f> 0b 90 90 e9 43 ff ff ff e8 58 f9 f9 fc 0f b6 1d 26 cb a7 0b 31
RSP: 0018:ffffc90000708be8 EFLAGS: 00010082
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff815a5139
RDX: ffff88801dee2440 RSI: ffffffff815a5146 RDI: 0000000000000001
RBP: ffff8880492acdd8 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff8880492acdd8
R13: ffff888051736800 R14: 0000000000000007 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88806a900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd659afe80 CR3: 0000000024a66000 CR4: 0000000000352ef0
Call Trace:
 <IRQ>
 __refcount_sub_and_test include/linux/refcount.h:275 [inline]
 __refcount_dec_and_test include/linux/refcount.h:307 [inline]
 refcount_dec_and_test include/linux/refcount.h:325 [inline]
 p9_req_put+0x1ec/0x250 net/9p/client.c:404
 req_done+0x1e7/0x2f0 net/9p/trans_virtio.c:147
 vring_interrupt drivers/virtio/virtio_ring.c:2715 [inline]
 vring_interrupt+0x31b/0x400 drivers/virtio/virtio_ring.c:2690
 __handle_irq_event_percpu+0x229/0x7d0 kernel/irq/handle.c:158
 handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
 handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:210
 handle_edge_irq+0x263/0xd10 kernel/irq/chip.c:831
 generic_handle_irq_desc include/linux/irqdesc.h:173 [inline]
 handle_irq arch/x86/kernel/irq.c:247 [inline]
 call_irq_handler arch/x86/kernel/irq.c:259 [inline]
 __common_interrupt+0xdf/0x250 arch/x86/kernel/irq.c:285
 common_interrupt+0x61/0xe0 arch/x86/kernel/irq.c:278
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693
RIP: 0010:handle_softirqs+0x1da/0x8f0 kernel/softirq.c:547
Code: 89 44 24 18 48 89 6c 24 10 48 c7 c7 e0 77 6b 8b e8 3b 92 cd 09 65 66 c7 05 d9 8a a7 7e 00 00 e8 dc 6a 45 00 fb bb ff ff ff ff <49> c7 c6 c0 b0 e0 8d 41 0f bc dc 83 c3 01 0f 85 a4 00 00 00 e9 b1
RSP: 0018:ffffc90000708f28 EFLAGS: 00000202
RAX: 00000000000004e6 RBX: 00000000ffffffff RCX: 1ffffffff20bdf11
RDX: 0000000000000000 RSI: ffffffff8b6cd9e0 RDI: ffffffff8bd1ed20
RBP: ffff88801dee2440 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff905f3bd7 R11: 0000000000000000 R12: 0000000000000200
R13: 000000000000000a R14: 0000000000000001 R15: 0000000000000000
 __do_softirq kernel/softirq.c:595 [inline]
 invoke_softirq kernel/softirq.c:435 [inline]
 __irq_exit_rcu+0x109/0x170 kernel/softirq.c:662
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678
 common_interrupt+0xbf/0xe0 arch/x86/kernel/irq.c:278
 </IRQ>
 <TASK>
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693
RIP: 0010:active_load_balance_cpu_stop+0x364/0xde0 kernel/sched/fair.c:12029
Code: 00 4c 89 e7 85 c0 0f 85 b7 02 00 00 48 83 c7 18 e8 21 58 09 00 4c 89 e7 e8 e9 56 fc ff e8 04 4a 35 00 fb 48 8b 8d d0 fe ff ff <48> b8 00 00 00 00 00 fc ff df 48 01 c1 48 c7 01 00 00 00 00 48 c7
RSP: 0018:ffffc900006cfcc8 EFLAGS: 00000202
RAX: 00000000000004e3 RBX: 000000000000a2fa RCX: 1ffff920000d9fa2
RDX: 0000000000000000 RSI: ffffffff8b6cd9e0 RDI: ffffffff8bd1ed20
RBP: ffffc900006cfe20 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff905f3bd7 R11: 0000000000000001 R12: ffff88806a83ebc0
R13: ffff888028612440 R14: ffff88806a83f9e0 R15: ffff88806a93ebc0
 cpu_stopper_thread+0x21b/0x490 kernel/stop_machine.c:511
 smpboot_thread_fn+0x661/0xa30 kernel/smpboot.c:164
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
----------------
Code disassembly (best guess):
   0:	89 44 24 18          	mov    %eax,0x18(%rsp)
   4:	48 89 6c 24 10       	mov    %rbp,0x10(%rsp)
   9:	48 c7 c7 e0 77 6b 8b 	mov    $0xffffffff8b6b77e0,%rdi
  10:	e8 3b 92 cd 09       	call   0x9cd9250
  15:	65 66 c7 05 d9 8a a7 	movw   $0x0,%gs:0x7ea78ad9(%rip)        # 0x7ea78af8
  1c:	7e 00 00
  1f:	e8 dc 6a 45 00       	call   0x456b00
  24:	fb                   	sti
  25:	bb ff ff ff ff       	mov    $0xffffffff,%ebx
* 2a:	49 c7 c6 c0 b0 e0 8d 	mov    $0xffffffff8de0b0c0,%r14 <-- trapping instruction
  31:	41 0f bc dc          	bsf    %r12d,%ebx
  35:	83 c3 01             	add    $0x1,%ebx
  38:	0f 85 a4 00 00 00    	jne    0xe2
  3e:	e9                   	.byte 0xe9
  3f:	b1                   	.byte 0xb1