Sharing I/O Memory

Wesley Miaw wesley at wesman.net
Mon Jan 30 20:35:45 CET 2012


Hi,

>> I couldn't find any way to revoke access once granted via sigma0. Or
>> for a L4 userland process to "put back" the memory it has previous
>> requested access to.
>
> Processes can unmap their memory themselves, or those inbetween. Just
> not sigma0 because that's not its task. io is handling everything non-ram
> for multiple clients etc. I'd think of the normal side as a device which
> has some (big) MMIO and handle it that way on the secure side. Why would
> you like to get rid of the memory again?

I thought if I had a process release its memory then another process could
be granted it. And so I could map and then unmap for reach request. But it
sounds like I should look into the io server a bit more, or re-read
through how moe can configure things.

Thanks,
-- 
Wesley Miaw





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