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From: Niklaus Giger <niklaus.giger@member.fsf.org>
To: Matt Porter <mporter@kernel.crashing.org>
Date: Wed, 25 May 2005 13:31:22 +0200
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Subject: Re: Newbie question about accessing memory in kernel space
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Am Dienstag, 24. Mai 2005 22.31 schrieb Matt Porter:
> On Tue, May 24, 2005 at 09:19:28PM +0200, Niklaus Giger wrote:
> > Hi

> > Oops: kernel access of bad area, sig: 11 [#1]
>
> <snip>
>
> > What is wrong with my code?
>
> You mapped the device into user virtual address space.  The TLB
> replacement code is unable to load a TLB entry for a page outside
> of kernel space...so you crash.
>
> Don't use io_block_map()...it allows you to shoot yourself in the
> foot very easily (as you just witnessed). Use ioremap() to map
> your device.
ioremap() fixed my problem.

Thanks a lot for your help.

Best regards

Niklaus