2005-01-07 12:34:26

by Mathieu Fluhr

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Subject: USB Storage "delay" when using udev

Hello

I don't know if someone has already fix this, but in the 2.6.x kernels,
when using udev file system, you encouter some kind of delay (something
like 2 or 3 seconds) when you plug in a USB hotplug device (like CD
recorder, or whatever...).

I explain :

Normally, when you plug in such a device, the usb-storage module creates
a SCSI Generic device connected to your device for using it and adds it
to the /proc/scsi/scsi file.

With udev, it seems (I say it seems because I did not check the kernel
source yet) that the kernel is adding the SCSI Generic device in
the /proc file 2-3 seconds BEFORE this device gets useable (tested with
sg_scan).

Is it "normal" ?

Best Regards,
Mathieu