Re: [PATCH 0/3] x86/microcode: support for microcode update in Xen dom0

Jeremy Fitzhardinge
2011-10-13T00:00:48Z

On 10/12/2011 04:55 PM, H. Peter Anvin wrote:
> On 10/12/2011 04:40 PM, Jeremy Fitzhardinge wrote:
>> On 10/12/2011 03:49 PM, H. Peter Anvin wrote:
>>> The stickiest part of all of this is where to leave the microcode so
>>> the kernel can get to it way early. We could use the linked list, but
>>> that would mean bootloader enabling; another idea was to stick it as a
>>> prefix to the initramfs identified by a signature.
>>
>> I think it would be easiest for the multiboot case if it were a separate
>> file, but I don't feel I'm really up on all the details.
>
> For the multiboot case, yes of course.
>
> Some bootloaders allow initramfs to be concatenated from multiple
> files; unfortunately I'm not sure if Grub ever grew that capability.
> Sigh.

Presumably we'd want some way to make all possible microcode files
available to the hypervisor/kernel so that there's no need to construct
the bootloader config for a specific CPU vendor (or worse, CPU model).
So that would need either some way of specifying multiple files, or a
wrapper which can contain multiple files?

J