Well, sort of or not. You have a mirrored region for kernel- accessed read-only memory regions where the kernel potentially might write to. You don't need a mirrored region for all writable pages.
Seb
-----Original Message----- From: Espen Skoglund [mailto:esk@ira.uka.de] Sent: Mittwoch, 7. November 2001 13:31 To: Sebastian Schoenberg Cc: jhuntnz@users.sourceforge.net; l4-hackers@os.inf.tu-dresden.de Subject: RE: l4 for 386
[Sebastian Schoenberg]
This can be done by using different regions for read and write access. For tasks where the write-protection is neccesary, a page is mapped only to the writeable area if the page is writable in the page-table.
I'm not sure I know what you mean here. Are you suggesting that we divide the user-accessible virtual memory into two equally sized mirrored regions; one for read-only and one for read-write?
eSk
l4-hackers@os.inf.tu-dresden.de