------------[ cut here ]------------
refcount_read(&tsk->usage)
WARNING: kernel/fork.c:779 at __put_task_struct+0x33c/0x400 kernel/fork.c:779, CPU#1: kworker/1:4/5293
Modules linked in:
CPU: 1 UID: 0 PID: 5293 Comm: kworker/1:4 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:__put_task_struct+0x33c/0x400 kernel/fork.c:779
Code: 4c 89 e6 e8 26 e9 98 00 e9 f2 fe ff ff e8 2c b2 3d 00 be 03 00 00 00 4c 89 e7 e8 cf af 58 01 e9 db fe ff ff e8 15 b2 3d 00 90 <0f> 0b 90 e8 0c b2 3d 00 65 48 3b 1d dc 25 81 0b 0f 85 64 fd ff ff
RSP: 0018:ffffc900001a8e00 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff88810ef81d80 RCX: ffffffff8174478b
RDX: ffff888119b2d880 RSI: ffffffff81744a2b RDI: ffff888119b2d880
RBP: 00000000c0000000 R08: 0000000000000005 R09: 0000000000000000
R10: 00000000c0000000 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff888119b2d880 R14: ffffffff8198896d R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8882687c9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0847262000 CR3: 000000011718c000 CR4: 00000000003506f0
Call Trace:
rcu_do_batch kernel/rcu/tree.c:2617 [inline]
rcu_core+0x5a2/0x10d0 kernel/rcu/tree.c:2869
handle_softirqs+0x1de/0x9d0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xed/0x150 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0x8f/0xb0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2039 [inline]
RIP: 0010:vprintk_emit+0x553/0x6b0 kernel/printk/printk.c:2478
Code: 00 4d 85 ed 0f 85 1b 01 00 00 e8 18 60 20 00 9c 5d 81 e5 00 02 00 00 31 ff 48 89 ee e8 e6 5a 20 00 48 85 ed 0f 85 27 01 00 00 f8 5f 20 00 45 31 c9 41 b8 01 00 00 00 31 c9 48 8d 05 00 00 00
RSP: 0018:ffffc9000583ec60 EFLAGS: 00000246
RAX: 0000000000100000 RBX: 000000000000002a RCX: ffffc90014681000
RDX: 0000000000100000 RSI: ffffffff81919d64 RDI: ffff888119b2d880
RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff92000b07d8e
R13: 0000000000000200 R14: ffff88810529d880 R15: ffffc9000583ed88
__warn_printf lib/bug.c:188 [inline]
__report_bug.cold+0x7b/0x137 lib/bug.c:241
report_bug_entry+0xe1/0x290 lib/bug.c:266
handle_bug+0x1cd/0x2a0 arch/x86/kernel/traps.c:430
exc_invalid_op+0x17/0x50 arch/x86/kernel/traps.c:489
asm_exc_invalid_op+0x1a/0x20 arch/x86/include/asm/idtentry.h:616
RIP: 0010:refcount_warn_saturate+0x111/0x130 lib/refcount.c:25
Code: 04 e8 63 01 e5 fe 48 8d 3d bc 97 27 08 67 48 0f b9 3a e8 52 01 e5 fe 5b 5d c3 cc cc cc cc e8 46 01 e5 fe 48 8d 3d af 97 27 08 <67> 48 0f b9 3a e8 35 01 e5 fe 5b 5d e9 ce cf 9f 04 48 89 df e8 86
RSP: 0018:ffffc9000583ef30 EFLAGS: 00010246
RAX: 0000000000100000 RBX: ffff88810ef81da8 RCX: ffffc90014681000
RDX: 0000000000100000 RSI: ffffffff82ccfafa RDI: ffffffff8af492b0
RBP: 0000000000000002 R08: 0000000000000005 R09: 0000000000000004
R10: 0000000000000002 R11: 0000000000155cc0 R12: ffff88813a79c000
R13: ffff88810ef81da8 R14: 0000000000000001 R15: 0000000000000001
__refcount_add include/linux/refcount.h:289 [inline]
__refcount_inc include/linux/refcount.h:366 [inline]
refcount_inc include/linux/refcount.h:383 [inline]
get_task_struct include/linux/sched/task.h:116 [inline]
kthread_stop+0x602/0x680 kernel/kthread.c:754
rsi_kill_thread drivers/net/wireless/rsi/rsi_common.h:78 [inline]
rsi_91x_deinit+0x102/0x1f0 drivers/net/wireless/rsi/rsi_91x_main.c:405
rsi_probe+0xd27/0x1aa0 drivers/net/wireless/rsi/rsi_91x_usb.c:861
usb_probe_interface+0x303/0x8f0 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:643 [inline]
really_probe+0x241/0xa60 drivers/base/dd.c:721
__driver_probe_device+0x1de/0x400 drivers/base/dd.c:863
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:893
__device_attach_driver+0x1df/0x340 drivers/base/dd.c:1021
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4d0 drivers/base/dd.c:1093
device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1148
bus_probe_device+0x64/0x160 drivers/base/bus.c:613
device_add+0x11d9/0x1950 drivers/base/core.c:3691
usb_set_configuration+0xd97/0x1c60 drivers/usb/core/message.c:2268
usb_generic_driver_probe+0xa1/0xe0 drivers/usb/core/generic.c:250
usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:291
call_driver_probe drivers/base/dd.c:643 [inline]
really_probe+0x241/0xa60 drivers/base/dd.c:721
__driver_probe_device+0x1de/0x400 drivers/base/dd.c:863
driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:893
__device_attach_driver+0x1df/0x340 drivers/base/dd.c:1021
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4d0 drivers/base/dd.c:1093
device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1148
bus_probe_device+0x64/0x160 drivers/base/bus.c:613
device_add+0x11d9/0x1950 drivers/base/core.c:3691
usb_new_device.cold+0x685/0x115c drivers/usb/core/hub.c:2695
hub_port_connect drivers/usb/core/hub.c:5567 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
port_event drivers/usb/core/hub.c:5871 [inline]
hub_event+0x314d/0x4af0 drivers/usb/core/hub.c:5953
process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276
process_scheduled_works kernel/workqueue.c:3359 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x6c3/0xcb0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
----------------
Code disassembly (best guess):
0: 00 4d 85 add %cl,-0x7b(%rbp)
3: ed in (%dx),%eax
4: 0f 85 1b 01 00 00 jne 0x125
a: e8 18 60 20 00 call 0x206027
f: 9c pushf
10: 5d pop %rbp
11: 81 e5 00 02 00 00 and $0x200,%ebp
17: 31 ff xor %edi,%edi
19: 48 89 ee mov %rbp,%rsi
1c: e8 e6 5a 20 00 call 0x205b07
21: 48 85 ed test %rbp,%rbp
24: 0f 85 27 01 00 00 jne 0x151
* 2a: e8 f8 5f 20 00 call 0x206027 <-- trapping instruction
2f: 45 31 c9 xor %r9d,%r9d
32: 41 b8 01 00 00 00 mov $0x1,%r8d
38: 31 c9 xor %ecx,%ecx
3a: 48 rex.W
3b: 8d .byte 0x8d
3c: 05 .byte 0x5
3d: 00 00 add %al,(%rax)