运行命令：

[root@east81 Desktop]# dmesg|grep usb

[0.211798] usbcore: registered new interface driver usbfs

[0.211801] usbcore: registered new interface driver hub

[0.211812] usbcore: registered new device driver usb

[0.513302] usb usb1: New USB device found, idVendor=1d6b, idProduct=0002

[0.513303] usb usb1: New USB device strings: Mfr=3, Product=2, SerialNumber=1

[0.513304] usb usb1: Product: xHCI Host Controller

[0.513304] usb usb1: Manufacturer: Linux 3.10.0-327.el7.x86_64 xhci-hcd

[0.513305] usb usb1: SerialNumber: 0000:00:14.0

[0.518700] usb usb2: New USB device found, idVendor=1d6b, idProduct=0003

[0.518701] usb usb2: New USB device strings: Mfr=3, Product=2, SerialNumber=1

[0.518702] usb usb2: Product: xHCI Host Controller

[0.518702] usb usb2: Manufacturer: Linux 3.10.0-327.el7.x86_64 xhci-hcd

[0.518703] usb usb2: SerialNumber: 0000:00:14.0

[0.525247] usbcore: registered new interface driver usbserial

[0.525249] usbcore: registered new interface driver usbserial_generic

[0.525252] usbserial: USB Serial support registered for generic

[0.529231] usbcore: registered new interface driver usbhid

[0.529232] usbhid: USB HID core driver

[0.870736] usb 1-4: new low-speed USB device number 2 using xhci_hcd

[1.040346] usb 1-4: New USB device found, idVendor=413c, idProduct=301a

[1.040348] usb 1-4: New USB device strings: Mfr=1, Product=2, SerialNumber=0

[1.040350] usb 1-4: Product: Dell MS116 USB Optical Mouse

[1.040350] usb 1-4: Manufacturer: PixArt

[1.040536] usb 1-4: ep 0x81 - rounding interval to 64 microframes, ep desc says 80 microframes

[1.042664] input: PixArt Dell MS116 USB Optical Mouse as /devices/pci0000:00/0000:00:14.0/usb1/1-4/1-4:1.0/input/input3

[1.043039] hid-generic 0003:413C:301A.0001: input,hidraw0: USB HID v1.11 Mouse [PixArt Dell MS116 USB Optical Mouse] on usb-0000:00:14.0-4/input0

[1.196265] usb 1-5: new low-speed USB device number 3 using xhci_hcd

[1.367920] usb 1-5: New USB device found, idVendor=413c, idProduct=2113

[1.367922] usb 1-5: New USB device strings: Mfr=0, Product=2, SerialNumber=0

[1.367923] usb 1-5: Product: Dell KB216 Wired Keyboard

[1.368111] usb 1-5: ep 0x81 - rounding interval to 128 microframes, ep desc says 192 microframes

[1.368113] usb 1-5: ep 0x82 - rounding interval to 256 microframes, ep desc says 384 microframes

[1.372549] input: Dell KB216 Wired Keyboard as /devices/pci0000:00/0000:00:14.0/usb1/1-5/1-5:1.0/input/input4

[1.423970] hid-generic 0003:413C:2113.0002: input,hidraw1: USB HID v1.11 Keyboard [Dell KB216 Wired Keyboard] on usb-0000:00:14.0-5/input0

[1.429641] input: Dell KB216 Wired Keyboard as /devices/pci0000:00/0000:00:14.0/usb1/1-5/1-5:1.1/input/input5

[1.480682] hid-generic 0003:413C:2113.0003: input,hidraw2: USB HID v1.11 Device [Dell KB216 Wired Keyboard] on usb-0000:00:14.0-5/input1

[root@east81 Desktop]# dmesg -c

这样就可以全部清空记录了。