__x64_sys_readlinkat+0xb7/0x100 do_syscall_64+0xbf/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f ------------[ cut here ]------------ percpu ref (css_release) <= 0 (0) after switching to atomic WARNING: lib/percpu-refcount.c:197 at percpu_ref_switch_to_atomic_rcu+0x3cc/0x480, CPU#1: syz-fuzzer/255 Modules linked in: CPU: 1 UID: 0 PID: 255 Comm: syz-fuzzer 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: 0000:ffff88800f427d68 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8139de70 RDX: ffff8880160bb700 RSI: ffffffff8139de7e RDI: 0000000000000001 RBP: 7fffffffffffffff R08: 0000000000000001 R09: ffffed100d9e4801 R10: 0000000000000000 R11: 0000000000000001 R12: ffff88803ca66380 R13: ffff88803ca663a0 R14: 0000000000000002 R15: 0000000000000003 FS: 000000c000030410(0000) GS:ffff8880e56dd000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055ceaa71c770 CR3: 000000000da7e000 CR4: 0000000000350ef0 Call Trace: rcu_core+0x7c8/0x1800 handle_softirqs+0x1b1/0x770 __irq_exit_rcu+0xc4/0x100 irq_exit_rcu+0x9/0x20 sysvec_apic_timer_interrupt+0x39/0x80 asm_sysvec_apic_timer_interrupt+0x1a/0x20 RIP: 0033:0x410717 Code: f6 c1 04 0f 85 44 01 00 00 80 78 09 00 0f 85 8c 00 00 00 48 8b 40 10 eb 5d 48 ff c2 48 83 c1 04 48 83 fa 08 73 3a 8b 5c 24 38 <39> 19 75 eb 0f b6 1c 02 80 fb 01 76 e2 48 8b 4c 24 28 0f b6 49 51 RSP: 002b:000000c00135b238 EFLAGS: 00000293 RAX: 000000c005b0f458 RBX: 00000000e7b64601 RCX: 000000c005b0f474 RDX: 0000000000000005 RSI: 0000000000957680 RDI: 0000000000000038 RBP: 000000c00135b250 R08: 0000000000000000 R09: 0000000000203000 R10: 0000000000000002 R11: 0000000000000011 R12: 00000000000000f1 R13: 0000000000000000 R14: 0000000000e5dacd R15: 0000000000000000 irq event stamp: 256214 hardirqs last enabled at (256222): [] __up_console_sem+0x78/0x80 hardirqs last disabled at (256233): [] __up_console_sem+0x5d/0x80 softirqs last enabled at (255766): [] handle_softirqs+0x50c/0x770 softirqs last disabled at (255775): [] __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 ffff88803ca66380 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 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 UDC core: USB Raw Gadget: couldn't find an available UDC or it's busy 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 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 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 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 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 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 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