Re: [PATCH] Align PCI memory regions to page size (4K) - Fix

Arjan van de Ven
2007-10-28T19:53:25Z

On Sun, 28 Oct 2007 13:27:27 -0400
"Barak Fargoun" <barak@neocleus.com> wrote:

> Sorry, my mail client corrupted the previous mail containing the
> patch... it should be ok now...
>
> Add a boot parameter (‘pci-mem-align’) which forces PCI memory
> regions to be aligned to 4K.
>
> This is very useful when developing an hypervisor, since in case we
> want to let native domains direct access to specific hardware, we
> don’t want PCI devices to share their memory region page with other
> devices. In Xen for example, PCI devices mmio resources are mapped by
> remapping complete pages (by Intel VT-d & the Neocleus pass-through
> patch for Xen).
>
> Signed-off-by: Barak Fargoun     (barak@neocleus.com)
> ---
> Kernel version: 2.6.18 (since this is the kernel version used
> in Xen for Dom-0) ---

I appreciate that Xen is about 2 years behind the curve and only uses
2.6.18, but what do you expect us on this list to do with this patch?
2.6.18 is no longer maintained: it doesn't get -stable updates anymore.
(And if it did, I doubt this kind of change would be suitable for a
-stable release anyway)...

so the first step really is to make a patch against 2.6.24-rc or a
later git version.... because then and only then is your patch
something that anyone else here can DO something with ...

(it's like the tree in the forest... if a tree falls in a forest, but
everyone moved to a different forest 2 years ago, does it make a sound?)

Greetings,
Arjan van de Ven

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