rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { P4117 } 6 jiffies s: 2905 root: 0x0/T
rcu: blocking rcu_node structures (internal RCU debug):

usb 6-1: new high-speed USB device number 2 using dummy_hcd
usb 6-1: Using ep0 maxpacket: 16
usb 6-1: config 1 interface 0 altsetting 0 endpoint 0xB has invalid wMaxPacketSize 0
usb 6-1: config 1 interface 0 altsetting 0 bulk endpoint 0xB has invalid maxpacket 0
usb 6-1: config 1 interface 0 altsetting 0 endpoint 0x8A has invalid wMaxPacketSize 0
usb 6-1: config 1 interface 0 altsetting 0 bulk endpoint 0x8A has invalid maxpacket 0
usb 6-1: New USB device found, idVendor=04e6, idProduct=0005, bcdDevice= 1.77
usb 6-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
ums-sddr09 6-1:1.0: USB Mass Storage device detected
ums-sddr09: probe of 6-1:1.0 failed with error -5
usb 6-1: USB disconnect, device number 2
usb 6-1: new high-speed USB device number 3 using dummy_hcd
usb 6-1: Using ep0 maxpacket: 16
usb 6-1: config 1 interface 0 altsetting 0 endpoint 0xB has invalid wMaxPacketSize 0
usb 6-1: config 1 interface 0 altsetting 0 bulk endpoint 0xB has invalid maxpacket 0
usb 6-1: config 1 interface 0 altsetting 0 endpoint 0x8A has invalid wMaxPacketSize 0
usb 6-1: config 1 interface 0 altsetting 0 bulk endpoint 0x8A has invalid maxpacket 0
usb 6-1: New USB device found, idVendor=04e6, idProduct=0005, bcdDevice= 1.77
usb 6-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
ums-sddr09 6-1:1.0: USB Mass Storage device detected
ums-sddr09: probe of 6-1:1.0 failed with error -5
usb 6-1: USB disconnect, device number 3