Re: udev and devfs - The final word

Andries Brouwer
2004-01-01T00:15:53Z

On Wed, Dec 31, 2003 at 03:19:22PM -0500, Rob Love wrote:

> We can get to the point where we don't even need the explicit concept of
> device numbers, but just "any old unique value" to use as a cookie. The
> kernel can pull that number from anywhere, and notify user-space via
> udev ala hotplug.

My plan has been to essentially use a hashed disk serial number
for this "any old unique value". The problem is that "any old"
is easy enough, but "unique" is more difficult.
Naming devices is very difficult, but in some important cases,
like SCSI or IDE disks, that would work and give a stable name.

The kernel must not invent consecutive numbers - that does not
lead to stable names. Setting this up correctly is nontrivial.