[PATCH] arm64: Add CMDLINE_EXTEND

[will.deacon@arm.com (Will Deacon)]

On Tue, Dec 06, 2016 at 10:28:19AM -0800, Geoff Levand wrote:
> On 12/06/2016 04:20 AM, Will Deacon wrote:
> > On Mon, Dec 05, 2016 at 09:41:06AM -0800, Geoff Levand wrote:
> >> On 12/05/2016 04:08 AM, Catalin Marinas wrote:
> >>> On Fri, Dec 02, 2016 at 02:17:02PM -0800, Geoff Levand wrote:
> >>>> The device tree code already supports CMDLINE_EXTEND,
> >>>> so add the config option to make it available on arm64.
> >>>
> >>> What's your use-case for this patch? Note that both CMDLINE_FORCE and
> >>> CMDLINE_EXTEND (if we introduce it) are ignored by the EFI stub.
> >>> However, we don't seem to have stated this anywhere.
> >>
> >> I use this in CoreOS, where we need to set "acpi=force" for
> >> arm64.  CoreOS uses a proper UEFI + grub.
> > 
> > So why can't you just set that in grub if you want to boot with ACPI?
> 
> That is how I originally did it, but it was suggested I
> do it in the kernel config.  See:
> 
>   https://github.com/coreos/scripts/pull/610
> 
> Is there any reason why we don't want arm64 to have
> CMDLINE_EXTEND?

I'm yet to see a good use-case for it.

Will