Re: serious performance regression due to NX patch

David Mosberger
2004-07-13T05:23:11Z

>>>>> On Tue, 13 Jul 2004 00:23:29 -0400 (EDT), Ingo Molnar <mingo@redhat.com> said:

Ingo> it's not just about the stack! It's a "is the value of the
Ingo> PROT_EXEC bit just an embelishment of /proc output or is it
Ingo> taken seriously" thing.

Fine, but it seems to me NX bit patch wasn't properly integrated with
VM_DATA_DEFAULT_FLAGS. In fact, if you hadn't changed the x86 version
of VM_DATA_DEFAULT_FLAGS and instead had in mm/mmap.c replaced the
macro with (VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE), then
things would have behaved exactly right with my patch applied and the
logic would make much more sense.

There would also need to be a small change to arch/ia64/mm/init.c, but
I'd be happy to take care of that.

--david