Re: mmap() on cdrom files fails since 2.6.9-rc2-bk2

[Ingo Molnar <mingo@elte.hu>]

* Jean Delvare <khali@linux-fr.org> wrote:

> Indeed, all files on which mmap was failing were located on noexec'd
> devices (although for the cdrom the noexec is not explicitely stated
> in my /etc/fstab file). Your patch fixes my problem, mmap on these
> devices is working again. Thanks!
> 
> Now I'm only curious as to why the problem only affected me. Since it
> looks like noexec is implied on cdrom devices, the problem should have
> affected everyone. Or are the "!pt_gnu_stack binaries" something rare?
> I admit I have no idea what it refers to.

it means you are running an older distro which was built with a gcc that
doesnt generate PT_GNU_STACK signatures in binaries yet. On the biggest
distros the transition to PT_GNU_STACK binaries coincided with the
transition to a 2.6 kernel, so only people who run newer kernels on
older distros are affected, which is relatively rare since most 'older
distros' are not 2.6-ready in a number of system-support areas.
(although the kernel itself of course must be able to run old code too.)

	Ingo