Talk:USB storage devices

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device descriptor read error

Some USB controllers will be loaded with the wrong USB standard applied (e.g. a USB 3.0 controller is initialized with a USB 2.0 kernel module assigned) causing a loss of performance and an error message that looks something like "device descriptor read/64, error -32" at boot time. A supposed fix I found involves issuing the following command as root: "echo -1 >/sys/module/usbcore/parameters/autosuspend". Since I don't have a USB storage device handy it's hard for me to verify that the performance impact was fixed, but I can verify that this at least supressed the error message. This also does not specifically pertain to USB storage devices, but there is not a wiki page specifically for general USB controller usage and I didn't find it in order to create one just to add a single troubleshooting step. Mynis (talk) 21:24, 14 December 2013 (UTC)

Mount ext4-formatted usb drive so it can be written by the user

Does USB storage devices#As normal user with mount work? When trying to use these option I get errors. I think extra steps, like 'chown'ing the directory, are needed. -- Karol (talk) 02:32, 18 November 2014 (UTC)

It works fine for me, the ownership of the mountpoint is set according to the gid= argument and its permission according to fmask= and dmask= - exactly the same as for the other files on the mounted drive. I.e., I get the following:
# mount -o gid=lahwaacz,fmask=113,dmask=002 /dev/sdb1 /mnt/
$ ll /mnt/
total 863M
drwxrwxr-x 14 root lahwaacz 8.0K Jan  1  1970 ./
drwxr-xr-x 18 root root     4.0K Nov  7 19:35 ../
drwxrwxr-x  2 root lahwaacz 8.0K Jun 21 12:25 app/
drwxrwxr-x  5 root lahwaacz 8.0K Sep 13 10:03 boot/
...
$ touch foo
$ ll /mnt/
total 863M
drwxrwxr-x 14 root lahwaacz 8.0K Dec  6 23:00 ./
drwxr-xr-x 18 root root     4.0K Nov  7 19:35 ../
drwxrwxr-x  2 root lahwaacz 8.0K Jun 21 12:25 app/
drwxrwxr-x  5 root lahwaacz 8.0K Sep 13 10:03 boot/
-rw-rw-r--  1 root lahwaacz    0 Dec  6 23:00 foo
...
What kind of errors do you get?
Edit: dumb me, I should have read the title first... I have tried it with a NTFS drive, not with ext4. The problem is likely in the gid= mount option, which is not filesystem independent (see mount(8)). In fact, it makes sense only on filesystems not storing Linux file permissions.
-- Lahwaacz (talk) 22:17, 6 December 2014 (UTC)