__x64_sys_io_uring_setup+0xc8/0x170
 do_syscall_64+0xbf/0x360
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
------------[ cut here ]------------
percpu ref (css_release) <= 0 (-1) after switching to atomic
WARNING: lib/percpu-refcount.c:197 at percpu_ref_switch_to_atomic_rcu+0x3cc/0x480, CPU#0: ksoftirqd/0/14
Modules linked in:
CPU: 0 UID: 0 PID: 14 Comm: ksoftirqd/0 Tainted: G        W           6.17.0-rc4-next-20250901 #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 c0 99 e2 84 e8 25 ac e9 fe 90 <0f> 0b 90 90 e9 2b ff ff ff e8 56 de 5f ff e9 9e fe ff ff e8 dc de
RSP: 0018:ffff888009617c70 EFLAGS: 00010282
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8139de70
RDX: ffff888009601b80 RSI: ffffffff8139de7e RDI: 0000000000000001
RBP: 7fffffffffffffff R08: 0000000000000001 R09: ffffed100d9c4801
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88800eb2b280
R13: ffff88800eb2b2a0 R14: 0000000000000002 R15: 0000000000000003
FS:  0000000000000000(0000) GS:ffff8880e55d8000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005569302a4033 CR3: 000000000ec47000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 rcu_core+0x7c8/0x1800
 handle_softirqs+0x1b1/0x770
 run_ksoftirqd+0x2e/0x60
 smpboot_thread_fn+0x41d/0x9d0
 kthread+0x3c8/0x740
 ret_from_fork+0x34b/0x430
 ret_from_fork_asm+0x1a/0x30
 </TASK>
irq event stamp: 7978478
hardirqs last  enabled at (7978488): [<ffffffff81541b18>] __up_console_sem+0x78/0x80
hardirqs last disabled at (7978497): [<ffffffff81541afd>] __up_console_sem+0x5d/0x80
softirqs last  enabled at (7978028): [<ffffffff813bafcc>] handle_softirqs+0x50c/0x770
softirqs last disabled at (7978033): [<ffffffff813bb3de>] run_ksoftirqd+0x2e/0x60
---[ end trace 0000000000000000 ]---
percpu_ref_switch_to_atomic_rcu: percpu_ref_switch_to_atomic_rcu(): percpu_ref underflow slab kmalloc-64 start ffff88800eb2b280 pointer offset 0 size 64
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pid=8614 comm=syz-executor.7
kmemleak: Found object by alias at 0x607f1a636cac
CPU: 1 UID: 0 PID: 8614 Comm: syz-executor.7 Tainted: G        W           6.17.0-rc4-next-20250901 #1 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xca/0x120
 __lookup_object+0x94/0xb0
 delete_object_full+0x27/0x70
 free_percpu+0x30/0x1160
 futex_hash_free+0x38/0xc0
 mmput+0x2d3/0x390
 do_exit+0x79d/0x2970
 do_group_exit+0xd3/0x2a0
 get_signal+0x2315/0x2340
 arch_do_signal_or_restart+0x80/0x790
 exit_to_user_mode_loop+0x8b/0x110
 do_syscall_64+0x2f7/0x360
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3e33fc2b19
Code: Unable to access opcode bytes at 0x7f3e33fc2aef.
RSP: 002b:00007f3e31538218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00007f3e340d5f68 RCX: 00007f3e33fc2b19
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f3e340d5f6c
RBP: 00007f3e340d5f60 R08: 000000000000000e R09: 0000000000000000
R10: 00000000000001e0 R11: 0000000000000246 R12: 00007f3e340d5f6c
R13: 00007ffdab579edf R14: 00007f3e31538300 R15: 0000000000022000
 </TASK>
kmemleak: Object (percpu) 0x607f1a636ca0 (size 16):
kmemleak:   comm "syz-executor.1", pid 284, jiffies 4295585318
kmemleak:   min_count = 1
kmemleak:   count = 0
kmemleak:   flags = 0x21
kmemleak:   checksum = 0
kmemleak:   backtrace:
 pcpu_alloc_noprof+0x87a/0x1170
 mm_init+0x99b/0x1170
 copy_process+0x3ab7/0x73c0
 kernel_clone+0xea/0x7f0
 __do_sys_clone+0xce/0x120
 do_syscall_64+0xbf/0x360
 entry_SYSCALL_64_after_hwframe+0x77/0x7f