Re: LANANA: To Pending Device Number Registrants

Guest section DW
2001-05-17T09:33:55Z

On Wed, May 16, 2001 at 09:35:09PM -0400, Jeff Garzik wrote:

> To inject a bit of concrete into this discussion, I note that block
> devices with dynamically assigned don't work with CONFIG_DEVFS and
> devfs=only. Block devices -require- majors currently, due to those
> !@#!@# arrays. However, devfs_register_blkdev always returns zero when
> devfs=only, even if its a block device and a dynamic major is requested.

Jeff, this is a non-issue.
These arrays you talk about are removed in a simple edit session -
I did it a handful of times - there is no problem there whatsoever.

What you are talking about is kernel-internal. We are free to do
whatever we like inside the kernel, and we have full information.
The only question is how to transmit device identity across the
kernel space/user space boundary.

Andries

[And my solution is to use cookies - 64-bit opaque numbers that
carry no information, and are generated at random by the kernel,
but with the properties: (i) things that have a device number
today keep this number, (ii) the random generation is such that
whenever possible chances are good that after a reboot the same
device will have the same number.]