15 Oct
1999
15 Oct
'99
9:26 p.m.
Hello,
I donŽt know very much about the i386-processor and Fiasco, therefore I would like to know if the following RMGR/Fiasco extensions are possible.
1) As default, no task has I/O port access. (CPL > IOPL or I/O permission bitmap pointer invalid)
2) A task asks via IPC the RMGR for I/O port access, e.g. port=0x80, length=4.
3) The RMGR checks, if port access can be granted. If yes, the RMGR decreases the tasks CPL and/or changes the tasks I/O permission bitmap.
==> Task is able to access port 0x80 - 0x83.
The main question: I donŽt know if a task is able to change the CPL or the I/O permission bitmap of another task.
Ciao, Christian
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Christian Stueble............stueble@ls6.cs.uni-dortmund.de
PubKey[BF7104F5].......fp=8678C5D3CAD9CD8C F1DDB8EC202F116A
To be or not to be is true... (apocrypha of George Boole)
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