Re: [patch 2/4] remove extra acpi_rsdp command line for efi

Vivek Goyal
2013-10-28T16:11:14Z

On Mon, Oct 28, 2013 at 10:51:19AM +0000, Matthew Garrett wrote:
> On Mon, Oct 28, 2013 at 06:45:32PM +0800, Dave Young wrote:
> > On 10/28/13 at 10:39am, Matthew Garrett wrote:
> > > On Mon, Oct 28, 2013 at 06:34:12PM +0800, Dave Young wrote:
> > > > On 10/28/13 at 10:12am, Matthew Garrett wrote:
> > > > > Right, but previously acpi_rsdp was passed automatically and now it
> > > > > won't be?
> > > >
> > > > Yes, it was. I'm removing them in kexec-tools patches for efi runtime support.
> > >
> > > If I upgrade kexec-tools and try to launch an old kernel, I now need to
> > > add an extra parameter?
> >
> > Yes, it should work by passing the acpi_rsdp= via --append
>
> Yes, that's my point. You're breaking old configurations by requiring
> the user to pass an additional argument.

Yes this is a problem. Of course solution is easy by always passing
acpi_rsdp on command line. But in long term this is a problem. In the
sense, I am not sure how to cleanup the kexec-tools code as things improve.
Now we will support the EFI properly and still pass acpi_rsdp always in
an effort to matain backward compatibility.

For a very long time kexec-tools were not automatically appending
acpi_rsdp and user were supposed to add it on command line. We were
carrying this change in kdump scripts and pushed this change into
kexec-tools. In hindsight, it looks like that hardcoding parameters
in kexec-tools is a bad idea. It is hard to get rid of them in future.

Thanks
Vivek