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SubjectRe: Memory access
Guillaume Lancelin wrote:
> Writing a device driver for a IO card, I have the following message from
> the kernel:
> Unable to handle kernel paging request at virtual address 000d0804.
> [then it gives the register values]
> Segmentation fault."
> This address (0xd0804) is the location of a "mailbox" reserved by the IO
> card, and from which commands are passed to the card.
> My question: is the kernel using or protecting this area of the memory,
> and is there a way to deprotect it??? (how dangerous!)

Sounds like you may want to look into ioremap() and maybe buy Linux
Device Drivers by Rubini (O'Reilly).

Have fun!

-----------------------. No wonder we didn't get this right first time
Eli Carter | through. It's not really all that horribly
eli.carter(at) `- complicated, but the _details_ kill you. Linus
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