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rabbull

Member

Registered: 2019-11-28

Posts: 2

[SOLVED] USB Disk Not Showing up in /dev

I'm trying to mount a USB disk but it just doesn't showing up in /dev. However it can be found in lsusb.

# lsusb
...
Bus 001 Device 025: ID 1609:3a04 Flash USB Disk
...

I also checked dmesg. When the disk was plugged in, the following messages were appended.

[ 7612.614252] usb 1-4: new high-speed USB device number 25 using xhci_hcd
[ 7612.755992] usb 1-4: New USB device found, idVendor=1609, idProduct=3a04, bcdDevice= 0.00
[ 7612.756002] usb 1-4: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 7612.756007] usb 1-4: Product: USB Disk
[ 7612.756012] usb 1-4: Manufacturer: Flash
[ 7612.756016] usb 1-4: SerialNumber: 3727042E984E375529613

And udevadm:

KERNEL[7788.578441] add      /devices/pci0000:00/0000:00:14.0/usb1/1-4 (usb)
KERNEL[7788.582191] add      /devices/pci0000:00/0000:00:14.0/usb1/1-4/1-4:1.0 (usb)
KERNEL[7788.582363] bind     /devices/pci0000:00/0000:00:14.0/usb1/1-4 (usb)
UDEV  [7788.646233] add      /devices/pci0000:00/0000:00:14.0/usb1/1-4 (usb)
UDEV  [7788.651484] add      /devices/pci0000:00/0000:00:14.0/usb1/1-4/1-4:1.0 (usb)
UDEV  [7788.659540] bind     /devices/pci0000:00/0000:00:14.0/usb1/1-4 (usb)

And xhci module was loaded:

$ lsmod | grep xhci
intel_xhci_usb_role_switch    16384  0
roles                  16384  1 intel_xhci_usb_role_switch
xhci_pci               20480  0
xhci_hcd              290816  1 xhci_pci

It seems good enough to me, but still no device node was found in /dev.

If you need more information to locate the error, tell me and I'll be glad to suppliment. Thanks in advance for any help.

Edit: The problem is fixed by rebooting the machine, but it's not possible to reboot every time plugging in a new usb disk

Last edited by rabbull (2020-05-17 15:04:07)

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 25,378

Re: [SOLVED] USB Disk Not Showing up in /dev

You need to reboot after a kernel update, because the old modules of your running kernel don't exist anymore, it won't be necessary for every time you plug in an usb stick if you didn't update the kernel during runtime.

rabbull

Member

Registered: 2019-11-28

Posts: 2

Re: [SOLVED] USB Disk Not Showing up in /dev

You need to reboot after a kernel update, because the old modules of your running kernel don't exist anymore, it won't be necessary for every time you plug in an usb stick if you didn't update the kernel during runtime.

Amazing! How did you manage to find out that I just did a kernel upgrade? It must have been the reason. Thanks!

By the way, is there a way to mark my question as SOLVED?

seth

Member

From: Won't reply 2 private help req

Registered: 2012-09-03

Posts: 77,809

Re: [SOLVED] USB Disk Not Showing up in /dev

Mark resolved threads by editing your initial posts subject - so others will know that there's no task left, but maybe a solution to find.

The usb_storage module wasn't loaded and couldn't be loaded because of the update. That's not visible from what you posted, but V1del made a very informed guess ;-)

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