On Wed, 28 Nov 2007, Rusty Russell wrote:
> On Wednesday 28 November 2007 05:14:47 Christoph Lameter wrote:
> > On Tue, 27 Nov 2007, Rusty Russell wrote:
> > > Have you considered moving x86-64's setup_per_cpu_areas into generic
> > > code? It's a bit messier because some archs might not have set up NUMA
> > > stuff yet, but it's logically generic...
> >
> > Yes that will happen later. This is just the early cleanup work. I
> > plan to generally bring the two x86 arches in line. The pda will be
> > folded into the per cpu area and after that its easy to do.
>
> Unfortunately, we tried to get rid of the x86-64 pda (like i386) but you lose
> the ability to use the stack protection config option. That's because it
> assumes that gs:0x68 (or something) is the stack canary; we need a YA gcc
> change to make this gs:__builtin_stack_canary_off (where gcc can emit
> __builtin_stack_canary_off as a weak absolute symbol, so we can override it
> for the kernel.
This works if you rebase the per cpu area at zero. gs:0x68 is still the
stack canary.
The i386 method does not work because the segment register does not
directly point to the pda.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
