From: "David Schwartz" <davids@webmaster.com>
To: "Alex Bligh - linux-kernel" <linux-kernel@alex.org.uk>
Cc: "Oliver Xymoron" <oxymoron@waste.org>, <linux-kernel@vger.kernel.org>
Subject: RE: Entropy from net devices - keyboard & IDE just as 'bad' [was Re: [PATCH] let Net Devices feed Entropy, updated (1/2)]
Date: Sun, 19 Aug 2001 15:30:13 -0700 [thread overview]
Message-ID: <NOEJJDACGOHCKNCOGFOMEEOCDEAA.davids@webmaster.com> (raw)
In-Reply-To: <481261630.998262525@[169.254.45.213]>
> $ cat /proc/interrupts
> CPU0
> 0: 1116302985 XT-PIC timer
> 1: 2 XT-PIC keyboard
> 2: 0 XT-PIC cascade
> 8: 1 XT-PIC rtc
> 9: 28980016 XT-PIC usb-uhci, eth0
> 14: 698146587 XT-PIC ide0
> 15: 5 XT-PIC ide1
> NMI: 0
> ERR: 0
>
> Shock horror - I can continually poll this and spot
> when an IRQ occurs.
To what level of accuracy do you think you can measure when interrupts
occur? From my tests, you can (if you max the processor and do no math on
the results) read /proc/interrupts about once every 30,000 instruction
cycles. This would still leave about 14 bits of entropy in each interrupt.
Overall, you're just making the system busier.
DS
next prev parent reply other threads:[~2001-08-19 22:30 UTC|newest]
Thread overview: 78+ messages / expand[flat|nested] mbox.gz Atom feed top
2001-08-16 4:36 [PATCH] Optionally let Net Devices feed Entropy Robert Love
2001-08-16 4:40 ` [PATCH] 2.4.9-pre4: Optionally let Net Devices feed Entropy (1/2) Robert Love
2001-08-16 4:42 ` [PATCH] 2.4.9-pre4: Optionally let Net Devices feed Entropy (2/2) Robert Love
2001-08-16 4:43 ` [PATCH] 2.4.8-ac5: let Net Devices feed Entropy (1/2) Robert Love
2001-08-16 4:44 ` [PATCH] 2.4.8-ac5: let Net Devices feed Entropy (2/2) Robert Love
2001-08-16 8:50 ` [PATCH] Optionally let Net Devices feed Entropy Francois Romieu
2001-08-16 14:50 ` Robert Love
2001-08-16 17:02 ` Francois Romieu
2001-08-16 19:28 ` Alex Bligh - linux-kernel
2001-08-16 20:19 ` D. Stimits
2001-08-17 0:47 ` Robert Love
2001-08-17 22:56 ` D. Stimits
2001-08-18 17:44 ` [PATCH] let Net Devices feed Entropy, updated (1/2) Robert Love
2001-08-18 23:41 ` Oliver Xymoron
2001-08-19 0:38 ` Rik van Riel
2001-08-19 3:33 ` Oliver Xymoron
2001-08-19 3:49 ` Robert Love
2001-08-21 7:17 ` Philipp Matthias Hahn
2001-08-19 18:46 ` Mike Castle
2001-08-19 3:12 ` Robert Love
2001-08-19 3:36 ` Oliver Xymoron
2001-08-19 3:41 ` Rik van Riel
2001-08-19 3:57 ` Robert Love
2001-08-19 3:56 ` Robert Love
2001-08-19 14:43 ` lists
2001-08-19 21:34 ` Alex Bligh - linux-kernel
2001-08-19 22:08 ` Entropy from net devices - keyboard & IDE just as 'bad' [was Re: [PATCH] let Net Devices feed Entropy, updated (1/2)] Alex Bligh - linux-kernel
2001-08-19 22:18 ` Alex Bligh - linux-kernel
2001-08-19 22:30 ` David Schwartz [this message]
2001-08-19 22:38 ` Alex Bligh - linux-kernel
2001-08-19 22:46 ` David Schwartz
2001-08-20 13:25 ` Alex Bligh - linux-kernel
2001-08-20 19:48 ` David Schwartz
2001-08-21 8:50 ` Alex Bligh - linux-kernel
2001-08-21 7:49 ` David Lang
2001-08-21 9:21 ` Alex Bligh - linux-kernel
2001-08-21 10:06 ` Entropy from net devices - keyboard & IDE just as 'bad' (better timing in random.c) Johan Adolfsson
2001-08-21 18:31 ` Entropy from net devices - keyboard & IDE just as 'bad' [was Re: [PATCH] let Net Devices feed Entropy, updated (1/2)] David Wagner
2001-08-21 21:53 ` Robert Love
2001-08-21 18:29 ` David Wagner
2001-08-21 21:57 ` Robert Love
2001-08-21 21:50 ` Robert Love
2001-08-19 17:08 ` [PATCH] let Net Devices feed Entropy, updated (1/2) Oliver Xymoron
2001-08-19 18:02 ` David Madore
2001-08-19 23:47 ` Oliver Xymoron
2001-08-19 21:19 ` Alex Bligh - linux-kernel
2001-08-19 22:24 ` David Ford
2001-08-20 10:02 ` Martin Dalecki
2001-08-20 10:34 ` Johan Adolfsson
2001-08-20 10:47 ` Martin Dalecki
2001-08-20 13:07 ` Johan Adolfsson
2001-08-20 13:57 ` Alex Bligh - linux-kernel
2001-08-20 14:25 ` Martin Dalecki
2001-08-21 1:11 ` Theodore Tso
2001-08-21 1:36 ` Richard Gooch
2001-08-21 9:43 ` Martin Dalecki
2001-08-21 9:59 ` Johan Adolfsson
2001-08-21 18:33 ` David Wagner
2001-08-21 17:19 ` Richard Gooch
2001-08-21 4:33 ` Robert Love
2001-08-20 16:15 ` Robert Love
2001-08-20 16:36 ` Robert Love
2001-08-22 6:10 ` Mike Touloumtzis
2001-08-22 8:54 ` Alex Bligh - linux-kernel
2001-08-22 13:47 ` Chris Friesen
2001-08-22 6:26 ` Robert Love
2001-08-22 17:27 ` Mike Touloumtzis
2001-08-19 20:58 ` Alex Bligh - linux-kernel
2001-08-19 22:19 ` Mike Castle
2001-08-19 22:29 ` Alex Bligh - linux-kernel
2001-08-20 2:26 ` Mike Castle
2001-08-20 23:08 ` Tom Rini
2001-08-18 5:57 ` [PATCH] Optionally let Net Devices feed Entropy Robert Love
2001-08-17 0:47 ` Robert Love
2001-08-17 14:34 ` Alex Bligh - linux-kernel
2001-08-17 0:47 ` Robert Love
2001-08-17 9:05 ` Francois Romieu
2001-08-17 15:00 ` Alex Bligh - linux-kernel
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