Linux emulation on FreeBSD AMD64

Roman Divacky rdivacky at freebsd.org
Sat Nov 3 03:52:55 PDT 2007


> Ok, I have fond what is so special with this memory. Oracle uses SYSV 
> shared memory, and comparing output from "ipcs -mb" and 
> /compat/linux/proc/<PID>/maps it's became clear that that suspiciously 
> looking too high addresses of memory chunks with missed execution bit 
> are SYSV shared memory areas.
> 
> > 50000000-55c00000 rw-p 05c83000 00:00 0 - this is main chunk which 
> can be seen in output of "show sga" sqlplus command
> 
> > 55c00000-55c01000 r--p 05c83000 00:00 0
> > 55c01000-55c81000 rw-p 05c83000 00:00 0
> > 55c81000-55c82000 r--p 05c83000 00:00 0
> > 55c82000-55c83000 rw-p 05c83000 00:00 0 - this are adjusted to the 
> end  small (4096) pieces
> 
> So, the question is what is changed in AMD64 arch with respect to SYSV 
> shared memory?
> Why vm_map_protect from /sys/vm/vm_mmap.c returns 
> KERN_PROTECTION_FAILURE in attempts to change protection of such type of 
> memory?

please try www.vlakno.cz/~rdivacky/pav.patch, I wrote that some time ago... it might
not apply cleanly.. I am sure you'll cope with that :)

please report back

roman

p.s. when replying please dont include WHOLE mail you reply to.. its very hard to read :(


More information about the freebsd-emulation mailing list