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Message-ID: <19f34abd0807010517w6e2003d6j86922df0aa0052ac@mail.gmail.com>
Date: Tue, 1 Jul 2008 14:17:48 +0200
From: "Vegard Nossum" <vegard.nossum@gmail.com>
To: "Andi Kleen" <andi@firstfloor.org>
Subject: Re: kmemcheck detected possible information leak to userspace?
Cc: "Evgeniy Polyakov" <johnpol@2ka.mipt.ru>, netdev@vger.kernel.org,
       "Pekka Enberg" <penberg@cs.helsinki.fi>, "Ingo Molnar" <mingo@elte.hu>,
       linux-kernel@vger.kernel.org
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On Tue, Jul 1, 2008 at 1:47 PM, Andi Kleen <andi@firstfloor.org> wrote:
> "Vegard Nossum" <vegard.nossum@gmail.com> writes:
>
>> But there is one thing I forgot: Is this memory initialized by DMA? If
>> so, the warning is bogus and I will go hide in shame.
>
> Yes it is.
>
> [btw that was something I noted during the initial review and was then
> ridiculed for]

I just went back and reviewed the original thread. (I assume you're
talking about the kmemcheck v3 thread,
http://lkml.org/lkml/2008/2/7/500.)

I'm sorry about having forgotten this particular comment you made.
Please take into account that before December last year, I didn't even
know what an skbuff was. And I didn't know how DMA worked. There can
be a lot of things that slip past when I don't have the basic mental
hooks on which to hang them. (Though, I must say, those discussions
have taught me a lot.) There was also the fact that Ingo for a long
time carried patches to silence these warnings, but which were dropped
before the 2.6.26 merge window because they should go through the
right maintainers instead of the x86 tree. I forgot about it, so I've
made a mistake this time.

But I don't see that you were ever ridiculed. In fact, I am only
grateful for all the comments you've made, and the help you've been.


Vegard

PS: The error I just reported was different from the ones we've had
before, which is why I didn't recognize it immediately.

-- 
"The animistic metaphor of the bug that maliciously sneaked in while
the programmer was not looking is intellectually dishonest as it
disguises that the error is the programmer's own creation."
	-- E. W. Dijkstra, EWD1036
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