Re: Problem with random.c and PPC

[Oliver Xymoron]

On Thu, Aug 15, 2002 at 06:50:32PM -0700, H. Peter Anvin wrote:
> Followup to:  <[e-mail]>
> By author:    Tom Rini <[e-mail]>
> In newsgroup: linux.dev.kernel
> > 
> > Ah, thanks.  In that case, no.  It doesn't look like the input-layer USB
> > keyboards contribute to entropy (but mice do), and I don't think the ADB
> > ones do.  I'll take a crack at adding this to keyboards monday maybe.
> > 
> 
> Be careful... USB devices are *always* going to speak at the same
> place in the USB cycle... I believe that is 1 ms.  Thus,
> submillisecond resolution is *not* random.

Currently not a problem for anyone except X86, as they'll only use HZ
resolution. But the same problem exists on regular mice and keyboards,
which are typically scanned for events at a fixed rate.

This is just the tip of the iceberg for problems with entropy
accounting. I've got some free time today, I'll try to clean up my
patches for this.

-- 
 "Love the dolphins," she advised him. "Write by W.A.S.T.E.."