Naive question about grant/map
voelp at os.inf.tu-dresden.de
Fri Dec 5 11:20:45 CET 2003
>I am looking for a sequence in which A maps to B and B ??? to C and the
>result would look like:
> A -> B
> A -> C
>Is there such an operation?
One possibility would be for B to request A to map the page on behalf of
B. This would result in the above graph. I think your question relates
to is there a possibility for A to avoid B mapping the page directly to
B, i.e. is there a way for A to enforce that the above graph can only be
created as such and particularly not in the form A - B - C. Do I get
We are currently thinking about ways to restrict communication such,
that this particular restriction is possible. The relevant question
1) Should B be allowed to send messages to C, but no mappings?
2) Should B be allowed to send messages to C, but C not back to B?
In the second case we need a way to restrict mapping such, that the
result is to map pages read only. Otherwise a read-writable
page can be used as a back channel from C to B.
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