Messages in this thread | | | Date | Sun, 27 Jun 2004 14:03:21 -0700 | From | Matthew Dharm <> | Subject | Re: drivers/block/ub.c |
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On Sun, Jun 27, 2004 at 01:29:45PM -0700, Pete Zaitcev wrote: > On Sun, 27 Jun 2004 11:23:10 -0400 (EDT) > Alan Stern <stern@rowland.harvard.edu> wrote: > > > + * -- use serial numbers to hook onto same hosts (same minor) after > > disconnect > > It was a poor wording by me. It refers to the drift of naming due to > increments in usb_host_id. After a disconnect and reconnect, /dev/uba1 > refers to the device, but /proc/partitions says "ubb". > > To correct this, I have to set gendisk->fist_minor before calling > add_disk(), but in order to do that, a driver has to track devices > somehow. A serial number looks like an obvious candidate for a key.
Serial numbers are unreliable for this. We've had a long history with this issue. Many devices do not provide a serial number. Many devices provide a serial number, but it is not a constant. Many devices provide invalid serial numbers.
Matt
-- Matthew Dharm Home: mdharm-usb@one-eyed-alien.net Maintainer, Linux USB Mass Storage Driver
IT KEEPS ASKING ME WHERE I WANT TO GO TODAY! I DONT WANT TO GO ANYWHERE! -- Greg User Friendly, 11/28/97 [unhandled content-type:application/pgp-signature] | |