From: Matt Mackall <mpm@selenic.com>
To: David Brownell <david-b@pacbell.net>
Cc: Denis Vlasenko <vda@ilport.com.ua>, Andrew Morton <akpm@osdl.org>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH 8/14] random: Remove SA_SAMPLE_RANDOM from USB gadget drivers
Date: Sat, 6 May 2006 13:31:12 -0500 [thread overview]
Message-ID: <20060506183112.GA15445@waste.org> (raw)
In-Reply-To: <200605061116.18274.david-b@pacbell.net>
On Sat, May 06, 2006 at 11:16:16AM -0700, David Brownell wrote:
> On Saturday 06 May 2006 4:07 am, Denis Vlasenko wrote:
> > On Friday 05 May 2006 19:42, Matt Mackall wrote:
> > > Remove SA_SAMPLE_RANDOM from USB gadget drivers
>
> It's conventional to post USB patches to linux-usb-devel, or at least
> to CC that list.
>
>
> > > There's no a priori reason to think that USB device interrupts will
> > > contain "entropy" as defined/required by /dev/random. In fact, most
> > > operations will be streaming and bandwidth- or CPU-limited.
> > > /dev/random needs unpredictable inputs such as human interaction or
> > > chaotic physical processes like turbulence manifested in disk seek
> > > times.
>
> And that'd be why you removed that SAMPLE_RANDOM from the Lubbock VBUS
> irqs ... which come from users connecting (by hand!) a USB cable. :)
Really I removed it because I want SAMPLE_RANDOM to go away and most
of the users were either pretty trivial (the Lubbock case), wrong (a
bunch of block devices, etc), or suspect (network, i2c).
> You shouldn't add spaces before labels, or change indents from
> pure-tab to tabs-plus-four-spaces.
Show me where I did that, please.
> Admittedly OMAP _now_ has access to the FIPS-certified hardware RNG,
> so for that platform it's hard to justify needing other entropy sources.
> But on the other hand, DMA completion IRQs aren't exactly predictable
> either, and it doesn't necessarily hurt to salt a high entropy pool
> with some less-high entropy inputs.
The sampling is fine. It's the _accounting_ that's at issue.
--
Mathematics is the supreme nostalgia of our time.
next prev parent reply other threads:[~2006-05-06 18:36 UTC|newest]
Thread overview: 58+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-05-05 16:42 [PATCH 1/14] random: Remove SA_SAMPLE_RANDOM from floppy driver Matt Mackall
2006-05-05 16:42 ` [PATCH 6/14] random: Remove redundant SA_SAMPLE_RANDOM from touchscreen drivers Matt Mackall
2006-05-05 16:42 ` [PATCH 4/14] random: Change cpqarray to use add_disk_randomness Matt Mackall
2006-05-05 16:42 ` [PATCH 2/14] random: Remove redundant SA_SAMPLE_RANDOM from NinjaSCSI Matt Mackall
2006-05-05 16:42 ` [PATCH 3/14] random: Make CCISS use add_disk_randomness Matt Mackall
2006-05-05 16:42 ` [PATCH 5/14] random: Remove bogus SA_SAMPLE_RANDOM from at91 compact flash driver Matt Mackall
2006-05-05 16:42 ` [PATCH 8/14] random: Remove SA_SAMPLE_RANDOM from USB gadget drivers Matt Mackall
2006-05-06 11:07 ` Denis Vlasenko
2006-05-06 18:16 ` David Brownell
2006-05-06 18:31 ` Matt Mackall [this message]
2006-05-05 16:42 ` [PATCH 7/14] random: Remove SA_SAMPLE_RANDOM from network drivers Matt Mackall
2006-05-05 17:13 ` Kyle Moffett
2006-05-05 17:24 ` Matt Mackall
2006-05-05 19:11 ` Theodore Tso
2006-05-05 20:30 ` Stephen Hemminger
2006-05-05 20:34 ` Matt Mackall
2006-05-06 11:55 ` Theodore Tso
2006-05-06 16:48 ` Matt Mackall
2006-05-06 17:29 ` Bernd Eckenfels
2006-05-06 18:05 ` Theodore Tso
2006-05-06 20:33 ` Matt Mackall
2006-05-07 0:17 ` David S. Miller
2006-05-07 1:22 ` Theodore Tso
2006-05-07 5:07 ` Matt Mackall
2006-05-08 21:58 ` Sami Farin
2006-05-24 22:47 ` Marcin Dalecki
2006-05-25 0:08 ` Theodore Tso
2006-05-31 19:29 ` Bill Davidsen
2006-05-07 0:08 ` David S. Miller
2006-05-07 4:59 ` Matt Mackall
2006-05-07 5:46 ` David S. Miller
2006-05-07 16:31 ` Matt Mackall
2006-05-07 13:13 ` Thiago Galesi
2006-05-07 16:00 ` Matt Mackall
2006-05-07 17:00 ` Thiago Galesi
2006-05-08 0:13 ` Theodore Tso
2006-05-08 2:55 ` Matt Mackall
2006-05-08 6:26 ` Pavel Machek
2006-05-08 7:07 ` David S. Miller
2006-05-08 14:05 ` Matt Mackall
2006-05-08 17:21 ` Pavel Machek
2006-05-08 17:27 ` Matt Mackall
2006-05-09 11:23 ` Pavel Machek
2006-05-11 10:05 ` Ph. Marek
2006-05-24 22:35 ` Marcin Dalecki
2006-05-05 21:10 ` David S. Miller
2006-05-05 23:03 ` Matt Mackall
2006-05-05 23:19 ` David S. Miller
2006-05-06 14:08 ` Folkert van Heusden
2006-05-06 15:19 ` Lee Revell
2006-05-07 10:35 ` Folkert van Heusden
2006-05-07 16:33 ` Matt Mackall
2006-05-05 16:42 ` [PATCH 9/14] random: Remove SA_SAMPLE_RANDOM from i2c drivers Matt Mackall
2006-05-05 16:42 ` [PATCH 10/14] random: Remove bogus SA_SAMPLE_RANDOM from mpc52xx serial driver Matt Mackall
2006-05-05 16:42 ` [PATCH 11/14] random: Remove UML usage of SA_SAMPLE_RANDOM Matt Mackall
2006-05-05 16:42 ` [PATCH 13/14] random: Remove SA_SAMPLE_RANDOM from IRQ fastpath Matt Mackall
2006-05-05 16:42 ` [PATCH 12/14] random: Remove not very useful SA_SAMPLE_RANDOM from lubbock Matt Mackall
2006-05-05 16:42 ` [PATCH 14/14] random: Remove add_interrupt_randomness Matt Mackall
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