============================= WARNING: suspicious RCU usage syzkaller #0 Not tainted ----------------------------- drivers/net/phy/phy_device.c:1831 suspicious rcu_dereference_protected() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 locks held by kworker/1:3/5816: 5, last CPU#1: #0: ffff8881052ded48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1461/0x1b10 kernel/workqueue.c:3470 #1: ffffc90001fefd18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3471 #2: ffff88810abd31d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline] #2: ffff88810abd31d8 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bb/0x4510 drivers/usb/core/hub.c:5917 #3: ffff8881077961d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline] #3: ffff8881077961d8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1073 #4: ffff8881137381a0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline] #4: ffff8881137381a0 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1073 stack backtrace: CPU: 1 UID: 0 PID: 5816 Comm: kworker/1:3 Not tainted syzkaller #0 PREEMPT(lazy) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026 Workqueue: usb_hub_wq hub_event Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 lockdep_rcu_suspicious.cold+0x4f/0xb2 kernel/locking/lockdep.c:6972 phy_detach_internal+0x6a5/0x830 drivers/net/phy/phy_device.c:1831 phylink_connect_phy drivers/net/phy/phylink.c:2452 [inline] phylink_connect_phy+0x22e/0x2b0 drivers/net/phy/phylink.c:2436 ax88772_init_phy drivers/net/usb/asix_devices.c:714 [inline] ax88772_bind+0xbb1/0x1520 drivers/net/usb/asix_devices.c:925 usbnet_probe+0xbb3/0x27e0 drivers/net/usb/usbnet.c:1812 usb_probe_interface+0x386/0x980 drivers/usb/core/driver.c:399 call_driver_probe drivers/base/dd.c:628 [inline] really_probe+0x241/0xa60 drivers/base/dd.c:706 __driver_probe_device+0x210/0x460 drivers/base/dd.c:868 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898 __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:503 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153 bus_probe_device+0x64/0x160 drivers/base/bus.c:623 device_add+0x121d/0x1970 drivers/base/core.c:3776 usb_set_configuration+0xd97/0x1dc0 drivers/usb/core/message.c:2279 usb_generic_driver_probe+0xa1/0xe0 drivers/usb/core/generic.c:250 usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:293 call_driver_probe drivers/base/dd.c:628 [inline] really_probe+0x241/0xa60 drivers/base/dd.c:706 __driver_probe_device+0x210/0x460 drivers/base/dd.c:868 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898 __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:503 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153 bus_probe_device+0x64/0x160 drivers/base/bus.c:623 device_add+0x121d/0x1970 drivers/base/core.c:3776 usb_new_device.part.0+0xcc2/0x1686 drivers/usb/core/hub.c:2713 usb_new_device drivers/usb/core/hub.c:5838 [inline] hub_port_connect drivers/usb/core/hub.c:5585 [inline] hub_port_connect_change drivers/usb/core/hub.c:5725 [inline] port_event drivers/usb/core/hub.c:5889 [inline] hub_event.cold+0x51a/0xe9d drivers/usb/core/hub.c:5971 process_one_work+0xac7/0x1b10 kernel/workqueue.c:3495 process_scheduled_works kernel/workqueue.c:3578 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3659 kthread+0x373/0x450 kernel/kthread.c:436 ret_from_fork+0x69f/0xc90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 asix 5-1:0.188 (unnamed net_device) (uninitialized): Could not connect PHY asix 5-1:0.188: probe with driver asix failed with error -22 usb 5-1: USB disconnect, device number 7 usb 5-1: new high-speed USB device number 8 using dummy_hcd usb 5-1: Using ep0 maxpacket: 32 usb 5-1: New USB device found: idVendor=17ef, idProduct=7203, bcdDevice=2e.36 usb 5-1: config 0 has an invalid interface number: 188 but max is 0 usb 5-1: config 0 has no interface number 0 usb 5-1: config 0 interface 188 altsetting 0 bulk endpoint 0x82 has invalid maxpacket 32 usb 5-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3 usb 5-1: Product: syz usb 5-1: Manufacturer: syz usb 5-1: SerialNumber: syz usb 5-1: config 0 descriptor?? asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -61 asix 5-1:0.188 (unnamed net_device) (uninitialized): Error reading Medium Status register: ffffffc3 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -32 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -32 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to write reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to enable software MII access asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -71 asix 5-1:0.188 (unnamed net_device) (uninitialized): Could not register MDIO bus (err -5) asix 5-1:0.188: probe with driver asix failed with error -5 usb 5-1: USB disconnect, device number 8 usb 5-1: new high-speed USB device number 9 using dummy_hcd usb 5-1: Using ep0 maxpacket: 32 usb 5-1: New USB device found: idVendor=17ef, idProduct=7203, bcdDevice=2e.36 usb 5-1: config 0 has an invalid interface number: 188 but max is 0 usb 5-1: config 0 has no interface number 0 usb 5-1: config 0 interface 188 altsetting 0 bulk endpoint 0x82 has invalid maxpacket 32 usb 5-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3 usb 5-1: Product: syz usb 5-1: Manufacturer: syz usb 5-1: SerialNumber: syz usb 5-1: config 0 descriptor?? asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0000: -32 asix 5-1:0.188 (unnamed net_device) (uninitialized): Error reading Medium Status register: ffffffe0 asix 5-1:0.188 (unnamed net_device) (uninitialized): Failed to read reg index 0x0002: -32 asix 5-1:0.188 (unnamed net_device) (uninitialized): Could not register MDIO bus (err -5) asix 5-1:0.188: probe with driver asix failed with error -5