PaX & ATI Troubles in 2.6.26 / 2.6.27

[Alex Deucher]

On Sun, Nov 23, 2008 at 9:06 AM, Klaus Kusche
<Klaus.Kusche at computerix.info> wrote:
> Dear PaX Team / ATI developers!
>
> I've had troubles after upgrading to the latest Xorg drivers with
> 2.6.26, and I've had even more troubles after upgrading to 2.6.27.
>
> Environment:
> * x86-64 pure (no 32 bit support), kernel with PaX (Gentoo-hardened)
> * ATI RV515 (Radeon X1300), Xorg server with "radeon" driver,
> drm enabled in kernel.
> * High-res text mode (no framebuffer) on console.
>
>
> Troubles in 2.6.26:
> 2.6.26 was already working fine,
> but after upgrading to the latest Xorg server, libs and drivers,
> the Xorg server process got a kernel null pointer when starting.
> The system was still alive, but the console was black & out of control
> (console switching did not work, nor did Alt-SysRq console kill).
>
> Turning off drm in the kernel solved the problem (but made X dog slow).
> I've no idea if this was PaX-related, I didn't suspect PaX at that time.
>
> (now that I have 2.6.27 up and running fine,
> I don't care any longer about these 2.6.26 problems).
>
>
> Troubles in 2.6.27:
> System rebooted while bringing up the kernel.
> Some initial kernel boot text lines displayed for tenths of a second,
> then came the BIOS counting memory...
> As far as I can tell, the reboot happened at the moment where
> the kernel tries to switch from VGA to high-res text mode
> (that's why I assume this is ATI-related...).
>

What are you using to achieve high-res text mode?  vesafb?  if so,
your problem probably lies there.

Alex