PowerPC paxtest results w/ gcc-4.1
Matt Sealey
matt at genesi-usa.com
Mon Aug 14 21:50:53 EST 2006
> Of course, that won't make all that much difference on your
> Cube, because the G4 CPU doesn't have hardware support for
> non-executable pages (any readable page is executable)
I don't think this is true?
Book I compatible PowerPC's have had a "no-executable" bit in
the page protection flags since the dark ages.. see page 7-38
and 7-39 of the 'Programming Environments Manual for 32-Bit
Microprocessors'.. this document predates even the G3.
As far as the documentation goes, you can make the page
readable and writable to the LSU, but the N bit causes the
instruction fetch to cause a machine check. That's pretty
"not-executable" to me at least :)
--
Matt Sealey <matt at genesi-usa.com>
Manager, Genesi, Developer Relations
More information about the Linuxppc-dev
mailing list