[meta-intel] meta-intel.inc: Update INTRD to INITRD_LIVE

[Robert Yang]

On 03/31/2016 09:19 AM, Robert Yang wrote:
>
>
> On 03/31/2016 02:39 AM, Patrick Ohly wrote:
>> On Wed, 2016-03-30 at 17:12 +0800, Robert Yang wrote:
>>>
>>> On 03/30/2016 04:45 PM, Patrick Ohly wrote:
>>>> Hello Saul!
>>>>
>>>> I noticed that you changed meta-intel.inc from extending INITRD to
>>>> INITRD_LIVE:
>>>>
>>>> meta-intel rev: cdbf029110327a51c0
>>>>
>>>>       This address a boot issue based on using the new bootimg code that
>>>>       makes a distiction between Live and VM type of image so they can
>>>>       co-exisit.
>>>>
>>>>    # for the early boot time kernel microcode loading support,
>>>>    # merge the microcode data in the final initrd image.
>>>> -INITRD_prepend = "${@bb.utils.contains('MACHINE_FEATURES', 'intel-ucode',
>>>> '${DEPLOY_DIR_IMAGE}/microcode.cpio ', '', d)}"
>>>> +INITRD_LIVE_prepend = "${@bb.utils.contains('MACHINE_FEATURES',
>>>> 'intel-ucode', '${DEPLOY_DIR_IMAGE}/microcode.cpio ', '', d)}"
>>>>
>>>>
>>>> In Ostro OS, we are not using bootimg. Our own code still uses INITRD,
>>>> which means that we no longer including the microcode.cpio in our
>>>> initramfs.
>>>
>>> I think that if you don't use booimg (live), but use vm (virtual machine) image,
>>> AFAIK, INITRD is a must for live image (hddimg, iso), but optional for vm image,
>>> if you are sure that only vm is needed, then you can change the line to:
>>>
>>> INITRD_VM_prepend = "${@bb.utils.contains('MACHINE_FEATURES', 'intel-ucode',
>>> '${DEPLOY_DIR_IMAGE}/microcode.cpio ', '', d)}"
>>
>> Now it gets even more confusing, with a third INITRD variant thrown into
>> the mix.
>>
>> Is it explained somewhere what these variables mean and when one is
>> supposed to use which variable?
>
> No, we should update the doc.
>
>>
>> INITRD_LIVE = "live boot CD"
>> INITRD_VM = "virtual machine"
>> INITRD = "real hardware"
>>
>> Something like that?
>
> You can't use INITRD if you want to build live and vm, otherwise, either
> of them will break. You can go on using INITRD, but there would be warnings.
>
>>
>> Either way, was the commit added to ensure that the live boot CD
>> continues to use microcode, or was it added to ensure that VM images do
>> not use it? Saul?
>
> INITRD_VM = "microcode.cpio" means the microcode.cpio will only be used
> by VM images. And if:
>
> INITRD_LIVE = "microcode.cpio" means the microdode.cpio will only be used
> by live images.

More info:

The vm image(hdddirect, vmdk, qcow2, vdi) and live image (hddimg, iso)
couldn't be built together because the following vars settings are
conflicted, for example:
   - SYSLINUX_ROOT (/dev/sda2 vs /dev/ram0)
   - LABELS (boot vs boot install)
   - INITRD (None vs live install)
   - SYSLINUX_CFG (see above)

The user should use SYSLINUX_ROOT_VM or SYSLINUX_ROOT_LIVE clearly to avoid the 
confusion, the similar to LABELS, INITRD, SYSLINUX_CFG.

>
> // Robert
>
>>
>>