Question on "mappings as cache"

Espen Skoglund esk at
Tue Dec 9 13:40:13 CET 2003

[Marcus Völp]
> Stefan Götz wrote:
>> 5. RM sends non-propagating request and waits for reply
>> 6. DSM checks validity and translates request
>> 7. DSM replies to RM

> In general the DSM should not be able to alter regions it is not
> managing, i.e. at least the receive window must be shrinked to the
> region, the fault occured in. On x86-Pistachio the hack of modifying
> BR0 in the UTCB of the faulting thread might work. On architectures
> that place BR0 in Registers this is not possible, so the steps 6 and
> 7 are required anyway.

I believe our intention is to change the specs so that this becomes
possible, e.g., by making the ExchangeRegisters system call more


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