Re: [PATCH] [ARM] Use AT() in the linker script to create correctprogram headers

[Dave Martin]

On Tue, Oct 09, 2012 at 11:37:06AM -0600, Jason Gunthorpe wrote:
> On Mon, Oct 08, 2012 at 11:24:13AM +0100, Dave Martin wrote:
> 
> > Partly this came from some side speculation about whether we could do
> > things like privileged read-only permissions on newer CPUs, for preventing
> > unintended or undesired writes to the kernel's code or read-only data.
> 
> Some other arches page protect the kernel, but that tends to be at
> odds with the desire to use huge pages for the kernel mapping, and
> independent of the load headers..

This wasn't so much about that headers themselves as about fragmentation
of the page permissions which makes it difficult to map everything using
huge pages / sections.  But as you say, there are conflicting concerns
here, and it seems not to be a priority.

Privileged write-protect is nice to have if non-disruptive, but not
essential.

Cheers
---Dave
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