Re: [PATCH v2] x86/boot: Use EFI setup data if provided

Borislav Petkov
2019-03-25T12:01:49Z

On Mon, Mar 25, 2019 at 10:36:33AM +0000, Junichi Nomura wrote:
> AFAIU, early parsing is new code in v5.1-rc1 to support kexec on systems
> with hotpluggable memory with KASLR enabled. For systems that requires the
> new feature, it may be ok to say "you need to use another kexec interface"
> and/or "you need new kexec-tools".

No, this exactly should *not* happen. kexec is already full of duct tape
- don't need any more of that.

So I suggested that efi_get_rsdp_addr() should exit early on in the
kexeced kernel but making this all play nice with the kexec-ed kernel,
as Dave suggests, is better.

Now, my next question is: why does the RDSP address need to come from
kexec(1) (by way of efi_setup_data) and why can't the kexec'ed kernel
figure it out itself by parsing the EFI tables in a similar way to
efi_get_rsdp_addr ?

--
Regards/Gruss,
Boris.

Good mailing practices for 400: avoid top-posting and trim the reply.