我最近在一台相对较旧的机器上安装了 Fedora 25 Server（HP Compaq dc7700 小型机）。它以前运行 Windows 10，但所有 USB 端口突然停止工作（我不记得此后是否工作过）；我安装了 Fedora，希望能解决 USB 问题。
我的理解是，当我插入USB设备后，它应该在运行时出现lsusb。但是，我只看到集线器，而不是设备（在本例中为键盘）：
[root@fedora zspitz]# lsusb
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 007 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 006 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
[root@fedora zspitz]# lsusb -t
/: Bus 07.Port 1: Dev 1, Class=root_hub, Driver=uhci_hcd/2p, 12M
/: Bus 06.Port 1: Dev 1, Class=root_hub, Driver=uhci_hcd/2p, 12M
/: Bus 05.Port 1: Dev 1, Class=root_hub, Driver=uhci_hcd/2p, 12M
/: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=uhci_hcd/2p, 12M
/: Bus 03.Port 1: Dev 1, Class=root_hub, Driver=uhci_hcd/2p, 12M
/: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/6p, 480M
/: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/4p, 480M
lsusb -v显示以下内容（大概在stderr），并散布着其余输出：
can't get device qualifier: Resource temporarily unavailable
can't get debug descriptor: Resource temporarily unavailable
我尝试了多个 USB 端口，结果相同。
键盘在其他（Windows）系统上正常工作。
如何确定这是硬件问题还是驱动程序问题（USB 设备或系统设备）？我可以采取哪些进一步的步骤来解决此问题？
完整输出libusb -v：
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 2.00
bDeviceClass 9 Hub
bDeviceSubClass 0
bDeviceProtocol 0 Full speed (or root) hub
bMaxPacketSize0 64
idVendor 0x1d6b Linux Foundation
idProduct 0x0002 2.0 root hub
bcdDevice 4.08
iManufacturer 3 Linux 4.8.6-300.fc25.x86_64 ehci_hcd
iProduct 2 EHCI Host Controller
iSerial 1 0000:00:1d.7
bNumConfigurations 1
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 25
bNumInterfaces 1
bConfigurationValue 1
iConfiguration 0
bmAttributes 0xe0
Self Powered
Remote Wakeup
MaxPower 0mA
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 1
bInterfaceClass 9 Hub
bInterfaceSubClass 0
bInterfaceProtocol 0 Full speed (or root) hub
iInterface 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x81 EP 1 IN
bmAttributes 3
Transfer Type Interrupt
Synch Type None
Usage Type Data
wMaxPacketSize 0x0004 1x 4 bytes
bInterval 12
Hub Descriptor:
bLength 9
bDescriptorType 41
nNbrPorts 6
wHubCharacteristic 0x000a
No power switching (usb 1.0)
Per-port overcurrent protection
bPwrOn2PwrGood 10 * 2 milli seconds
bHubContrCurrent 0 milli Ampere
DeviceRemovable 0x00
PortPwrCtrlMask 0xff
Hub Port Status:
Port 1: 0000.0100 power
Port 2: 0000.0100 power
Port 3: 0000.0100 power
Port 4: 0000.0100 power
Port 5: 0000.0100 power
Port 6: 0000.0100 power
can't get device qualifier: Resource temporarily unavailable
can't get debug descriptor: Resource temporarily unavailable
Device Status: 0x0001
Self Powered
Bus 007 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 1.10
bDeviceClass 9 Hub
bDeviceSubClass 0
bDeviceProtocol 0 Full speed (or root) hub
bMaxPacketSize0 64
idVendor 0x1d6b Linux Foundation
idProduct 0x0001 1.1 root hub
bcdDevice 4.08
iManufacturer 3 Linux 4.8.6-300.fc25.x86_64 uhci_hcd
iProduct 2 UHCI Host Controller
iSerial 1 0000:00:1d.2
bNumConfigurations 1
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 25
bNumInterfaces 1
bConfigurationValue 1
iConfiguration 0
bmAttributes 0xe0
Self Powered
Remote Wakeup
MaxPower 0mA
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 1
bInterfaceClass 9 Hub
bInterfaceSubClass 0
bInterfaceProtocol 0 Full speed (or root) hub
iInterface 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x81 EP 1 IN
bmAttributes 3
Transfer Type Interrupt
Synch Type None
Usage Type Data
wMaxPacketSize 0x0002 1x 2 bytes
bInterval 255
Hub Descriptor:
bLength 9
bDescriptorType 41
nNbrPorts 2
wHubCharacteristic 0x000a
No power switching (usb 1.0)
Per-port overcurrent protection
bPwrOn2PwrGood 1 * 2 milli seconds
bHubContrCurrent 0 milli Ampere
DeviceRemovable 0x00
PortPwrCtrlMask 0xff
Hub Port Status:
Port 1: 0000.0100 power
Port 2: 0000.0100 power
can't get debug descriptor: Resource temporarily unavailable
Device Status: 0x0001
Self Powered
Bus 006 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 1.10
bDeviceClass 9 Hub
bDeviceSubClass 0
bDeviceProtocol 0 Full speed (or root) hub
bMaxPacketSize0 64
idVendor 0x1d6b Linux Foundation
idProduct 0x0001 1.1 root hub
bcdDevice 4.08
iManufacturer 3 Linux 4.8.6-300.fc25.x86_64 uhci_hcd
iProduct 2 UHCI Host Controller
iSerial 1 0000:00:1d.1
bNumConfigurations 1
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 25
bNumInterfaces 1
bConfigurationValue 1
iConfiguration 0
bmAttributes 0xe0
Self Powered
Remote Wakeup
MaxPower 0mA
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 1
bInterfaceClass 9 Hub
bInterfaceSubClass 0
bInterfaceProtocol 0 Full speed (or root) hub
iInterface 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x81 EP 1 IN
bmAttributes 3
Transfer Type Interrupt
Synch Type None
Usage Type Data
wMaxPacketSize 0x0002 1x 2 bytes
bInterval 255
Hub Descriptor:
bLength 9
bDescriptorType 41
nNbrPorts 2
wHubCharacteristic 0x000a
No power switching (usb 1.0)
Per-port overcurrent protection
bPwrOn2PwrGood 1 * 2 milli seconds
bHubContrCurrent 0 milli Ampere
DeviceRemovable 0x00
PortPwrCtrlMask 0xff
Hub Port Status:
Port 1: 0000.0100 power
Port 2: 0000.0100 power
can't get debug descriptor: Resource temporarily unavailable
Device Status: 0x0001
Self Powered
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 1.10
bDeviceClass 9 Hub
bDeviceSubClass 0
bDeviceProtocol 0 Full speed (or root) hub
bMaxPacketSize0 64
idVendor 0x1d6b Linux Foundation
idProduct 0x0001 1.1 root hub
bcdDevice 4.08
iManufacturer 3 Linux 4.8.6-300.fc25.x86_64 uhci_hcd
iProduct 2 UHCI Host Controller
iSerial 1 0000:00:1d.0
bNumConfigurations 1
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 25
bNumInterfaces 1
bConfigurationValue 1
iConfiguration 0
bmAttributes 0xe0
Self Powered
Remote Wakeup
MaxPower 0mA
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 1
bInterfaceClass 9 Hub
bInterfaceSubClass 0
bInterfaceProtocol 0 Full speed (or root) hub
iInterface 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x81 EP 1 IN
bmAttributes 3
Transfer Type Interrupt
Synch Type None
Usage Type Data
wMaxPacketSize 0x0002 1x 2 bytes
bInterval 255
Hub Descriptor:
bLength 9
bDescriptorType 41
nNbrPorts 2
wHubCharacteristic 0x000a
No power switching (usb 1.0)
Per-port overcurrent protection
bPwrOn2PwrGood 1 * 2 milli seconds
bHubContrCurrent 0 milli Ampere
DeviceRemovable 0x00
PortPwrCtrlMask 0xff
Hub Port Status:
Port 1: 0000.0100 power
Port 2: 0000.0100 power
can't get debug descriptor: Resource temporarily unavailable
Device Status: 0x0001
Self Powered
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 2.00
bDeviceClass 9 Hub
bDeviceSubClass 0
bDeviceProtocol 0 Full speed (or root) hub
bMaxPacketSize0 64
idVendor 0x1d6b Linux Foundation
idProduct 0x0002 2.0 root hub
bcdDevice 4.08
iManufacturer 3 Linux 4.8.6-300.fc25.x86_64 ehci_hcd
iProduct 2 EHCI Host Controller
iSerial 1 0000:00:1a.7
bNumConfigurations 1
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 25
bNumInterfaces 1
bConfigurationValue 1
iConfiguration 0
bmAttributes 0xe0
Self Powered
Remote Wakeup
MaxPower 0mA
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 1
bInterfaceClass 9 Hub
bInterfaceSubClass 0
bInterfaceProtocol 0 Full speed (or root) hub
iInterface 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x81 EP 1 IN
bmAttributes 3
Transfer Type Interrupt
Synch Type None
Usage Type Data
wMaxPacketSize 0x0004 1x 4 bytes
bInterval 12
Hub Descriptor:
bLength 9
bDescriptorType 41
nNbrPorts 4
wHubCharacteristic 0x000a
No power switching (usb 1.0)
Per-port overcurrent protection
bPwrOn2PwrGood 10 * 2 milli seconds
bHubContrCurrent 0 milli Ampere
DeviceRemovable 0x00
PortPwrCtrlMask 0xff
Hub Port Status:
Port 1: 0000.0100 power
Port 2: 0000.0100 power
Port 3: 0000.0100 power
Port 4: 0000.0100 power
can't get device qualifier: Resource temporarily unavailable
can't get debug descriptor: Resource temporarily unavailable
Device Status: 0x0001
Self Powered
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 1.10
bDeviceClass 9 Hub
bDeviceSubClass 0
bDeviceProtocol 0 Full speed (or root) hub
bMaxPacketSize0 64
idVendor 0x1d6b Linux Foundation
idProduct 0x0001 1.1 root hub
bcdDevice 4.08
iManufacturer 3 Linux 4.8.6-300.fc25.x86_64 uhci_hcd
iProduct 2 UHCI Host Controller
iSerial 1 0000:00:1a.1
bNumConfigurations 1
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 25
bNumInterfaces 1
bConfigurationValue 1
iConfiguration 0
bmAttributes 0xe0
Self Powered
Remote Wakeup
MaxPower 0mA
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 1
bInterfaceClass 9 Hub
bInterfaceSubClass 0
bInterfaceProtocol 0 Full speed (or root) hub
iInterface 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x81 EP 1 IN
bmAttributes 3
Transfer Type Interrupt
Synch Type None
Usage Type Data
wMaxPacketSize 0x0002 1x 2 bytes
bInterval 255
Hub Descriptor:
bLength 9
bDescriptorType 41
nNbrPorts 2
wHubCharacteristic 0x000a
No power switching (usb 1.0)
Per-port overcurrent protection
bPwrOn2PwrGood 1 * 2 milli seconds
bHubContrCurrent 0 milli Ampere
DeviceRemovable 0x00
PortPwrCtrlMask 0xff
Hub Port Status:
Port 1: 0000.0100 power
Port 2: 0000.0100 power
can't get debug descriptor: Resource temporarily unavailable
Device Status: 0x0001
Self Powered
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 1.10
bDeviceClass 9 Hub
bDeviceSubClass 0
bDeviceProtocol 0 Full speed (or root) hub
bMaxPacketSize0 64
idVendor 0x1d6b Linux Foundation
idProduct 0x0001 1.1 root hub
bcdDevice 4.08
iManufacturer 3 Linux 4.8.6-300.fc25.x86_64 uhci_hcd
iProduct 2 UHCI Host Controller
iSerial 1 0000:00:1a.0
bNumConfigurations 1
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 25
bNumInterfaces 1
bConfigurationValue 1
iConfiguration 0
bmAttributes 0xe0
Self Powered
Remote Wakeup
MaxPower 0mA
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 1
bInterfaceClass 9 Hub
bInterfaceSubClass 0
bInterfaceProtocol 0 Full speed (or root) hub
iInterface 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x81 EP 1 IN
bmAttributes 3
Transfer Type Interrupt
Synch Type None
Usage Type Data
wMaxPacketSize 0x0002 1x 2 bytes
bInterval 255
Hub Descriptor:
bLength 9
bDescriptorType 41
nNbrPorts 2
wHubCharacteristic 0x000a
No power switching (usb 1.0)
Per-port overcurrent protection
bPwrOn2PwrGood 1 * 2 milli seconds
bHubContrCurrent 0 milli Ampere
DeviceRemovable 0x00
PortPwrCtrlMask 0xff
Hub Port Status:
Port 1: 0000.0100 power
Port 2: 0000.0100 power
can't get debug descriptor: Resource temporarily unavailable
Device Status: 0x0001
Self Powered
完整输出lspci -nn：
00:00.0 Host bridge [0600]: Intel Corporation 82Q963/Q965 Memory Controller Hub [8086:2990] (rev 02)
00:02.0 VGA compatible controller [0300]: Intel Corporation 82Q963/Q965 Integrated Graphics Controller [8086:2992] (rev 02)
00:03.0 Communication controller [0780]: Intel Corporation 82Q963/Q965 HECI Controller [8086:2994] (rev 02)
00:19.0 Ethernet controller [0200]: Intel Corporation 82566DM Gigabit Network Connection [8086:104a] (rev 02)
00:1a.0 USB controller [0c03]: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #4 [8086:2834] (rev 02)
00:1a.1 USB controller [0c03]: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #5 [8086:2835] (rev 02)
00:1a.7 USB controller [0c03]: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #2 [8086:283a] (rev 02)
00:1b.0 Audio device [0403]: Intel Corporation 82801H (ICH8 Family) HD Audio Controller [8086:284b] (rev 02)
00:1c.0 PCI bridge [0604]: Intel Corporation 82801H (ICH8 Family) PCI Express Port 1 [8086:283f] (rev 02)
00:1d.0 USB controller [0c03]: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #1 [8086:2830] (rev 02)
00:1d.1 USB controller [0c03]: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #2 [8086:2831] (rev 02)
00:1d.2 USB controller [0c03]: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #3 [8086:2832] (rev 02)
00:1d.7 USB controller [0c03]: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #1 [8086:2836] (rev 02)
00:1e.0 PCI bridge [0604]: Intel Corporation 82801 PCI Bridge [8086:244e] (rev f2)
00:1f.0 ISA bridge [0601]: Intel Corporation 82801HO (ICH8DO) LPC Interface Controller [8086:2814] (rev 02)
00:1f.2 IDE interface [0101]: Intel Corporation 82801H (ICH8 Family) 4 port SATA Controller [IDE mode] [8086:2820] (rev 02)
答案1
这可能是机器的硬件问题，尤其是如果在安装了 Windows 的情况下出现这种间歇性行为。您可以尝试以下几项操作：
在进行一些文件传输时尝试其他一些 USB 设备，尤其是闪存驱动器。键盘可能没问题，但这将是另一个确认。
当您插入 USB 设备时，您可以执行 操作
ls -l /dev/disk/by-*来查看那里出现了什么，因为 USB 设备将在那里明确命名/列出。无论什么lsusb状态，这至少应该显示连接的设备（当它们停止工作时它们也可能消失......可能是另一个线索）。注意：lsusb 可能会关闭此信息，因此您可能看不到两者之间的区别。看起来您的机器混合使用了 1.0/2.0 集线器。据您所知，根据您机器的官方规格，这是否正确？更准确地说，您可以将使用/测试限制在 2.0 端口。
您可以尝试使用外部 USB 集线器，看看效果如何。例如，在 2.0 根集线器上使用外部集线器时，间歇性连接发生的频率是否会降低？
最后，您始终可以采取更直接的途径找到解决方案，并执行安装一个廉价的实验PCI-USB卡（不到 20 美元）通过使用类似的方法来查看问题是否完全消失。