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Date: Thu, 20 May 2004 15:57:34 -0700
From: David Schultz <das@FreeBSD.ORG>
To: Tomas Pluskal <plusik@pohoda.cz>
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cc: hackers@FreeBSD.ORG
Subject: Re: copyin() EFAULT
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On Wed, May 19, 2004, Tomas Pluskal wrote:
> I would like to ask you for help or explanation - why do I get EFAULT when
> invoking copyin() or fubyte() etc. I am writing a kernel module, and I
[...]
> So copying of some blocks was OK, and on some blocks it returned EFAULT.
> Why?

You will get EFAULT when you try to copy pages that are not mapped
in the user process.