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Date: Thu, 10 Mar 2005 09:24:11 +0300
From: Andrey Chernov <ache@nagual.pp.ru>
To: Poul-Henning Kamp <phk@phk.freebsd.dk>
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cc: current@FreeBSD.ORG
Subject: Re: [TEST(/review)] major/minor/devname fix
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On Wed, Mar 09, 2005 at 10:40:18PM +0100, Poul-Henning Kamp wrote:
> +dev_t
> +dev2udev(struct cdev *x)
> +{
> +	if (x == NULL)
> +		return (NODEV);
> +	return (x->si_inode ^ devfs_random());
> +}

...

> +	dp = devfs_itod(ud ^ devfs_random());


Why you try to use randomization here instead of sequental ordering (or 
reversing/shifting it)? In such small number of bits there is a big 
probability of collisions may occurse.

-- 
http://ache.pp.ru/