Re: Memory Read Error

[linux-os (Dick Johnson)]

On Tue, 18 Dec 2007, Robert Hancock wrote:

> shashi59 wrote:
>> I am newbie for Linux Kernel.How can I read the memory area like the range
>> between ffff0000 to ffffffff.Directly i read that area it shows some error
>> like this "unable to handle kernel paging request at virtual address
>> ffff0000". So,I don't know, how to solve this error .Please anyone help
>> me....
>
> First off, why are you trying to do this and how. Without such details
> it's impossible to answer this question.
>
> -- 
> Robert Hancock      Saskatoon, SK, Canada
> To email, remove "nospam" from hancockr@xxxxxxxxxxxxx
> Home Page: http://www.roberthancock.com/
>

A possible hint to the newbie, with possibly English as
his last language, check out ioremap() and ioremap_nocache().
Within the kernel, these calls should allow any address
to be read, even if nothing exists at that address.


Cheers,
Dick Johnson
Penguin : Linux version 2.6.22.1 on an i686 machine (5588.29 BogoMips).
My book : http://www.AbominableFirebug.com/
_


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