COFFMAN Steven <SCoffman@COVANSYS.com> writes:
Sorry if this was mentioned previously, but the status page for Fiasco (October 2000) mentions that Fiasco still doesn't have Flex I/O pages. Is this still the case with CVS?
I/O flexpages still are not implemented. Unfortunately, implementing it is not a top priority for us right now (as Fiasco and L4 mostly are used in research contexts), but it still would be nice to have. The priorities could change if an external user shows significant interest. We are currently looking for a student or a contributor to implement this feature. I believe it's not that difficult to do. Michael -- hohmuth@innocent.com, hohmuth@inf.tu-dresden.de http://home.pages.de/~hohmuth/
Hello, Am Montag, 18. Juni 2001 13:09 schrieben Sie:
COFFMAN Steven <SCoffman@COVANSYS.com> writes:
Sorry if this was mentioned previously, but the status page for Fiasco (October 2000) mentions that Fiasco still doesn't have Flex I/O pages. Is this still the case with CVS?
I/O flexpages still are not implemented. Unfortunately, implementing it is not a top priority for us right now (as Fiasco and L4 mostly are used in research contexts), but it still would be nice to have. The priorities could change if an external user shows significant interest. I am very interested in I/O flexpages and a working clans & chiefs concept to be able to improve the Perseus secure operating system project. ( http://www.krypt.cs.uni-sb.de/~perseus). And I have some students here which are interested in practical jobs. But of course they are more interested in security than in operating systems. Do you think that it would be possible to implement this features at the time of a software practical (about 6 month 6 h/week)?
We are currently looking for a student or a contributor to implement this feature. I believe it's not that difficult to do.
Michael
Another (maybe simpler) approach to prevent hardware access would be to allow the RMGR to completely decide whether subtasks are allowed to access I/O ports or not (e.g. configured in the config-file). This allows us to implement a trusted server task which executes these operations while enforcing a security policy. Of course this would be slower etc..... Ciao, Chris
Christian Stueble <stueble@cs.uni-sb.de> wrote:
I am very interested in I/O flexpages and a working clans & chiefs concept to be able to improve the Perseus secure operating system project. ( http://www.krypt.cs.uni-sb.de/~perseus). And I have some students here which are interested in practical jobs. But of course they are more interested in security than in operating systems. Do you think that it would be possible to implement this features at the time of a software practical (about 6 month 6 h/week)?
We have a student looking at I/O flexpages in L4Ka/Hazelnut/x86. Tiny parts of the implementation were done by me earlier this year mostly as debugging aids. There are a few things that come with CPL>IOPL that make the implementation a bit more interesting (thinking of CLI/STI and friends). Cheers, Uwe ====== Just when I knew all life's answers they changed the questions. ===== Uwe Dannowski University of Karlsruhe, System Architecture Group 76128 Karlsruhe, Germany Tel: +49-721-6088970, Fax: +49-721-6087664 mailto:Uwe.Dannowski@ira.uka.de http://i30www.ira.uka.de/~dannowsk/
participants (3)
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Christian Stueble -
Michael Hohmuth -
Uwe Dannowski