Re: [qemu-s390x] [PATCH] s390-bios: Skip bootmap signature entries

[Christian Borntraeger]

On 06.05.19 13:05, Cornelia Huck wrote:
> On Mon, 6 May 2019 12:46:50 +0200
> Christian Borntraeger <address@hidden> wrote:
> 
>> On 06.05.19 12:34, Cornelia Huck wrote:
>>> On Mon, 6 May 2019 12:18:42 +0200
>>> Christian Borntraeger <address@hidden> wrote:
> 
>>>> I think we should not. Those entries might have sematic elements that the 
>>>> guest
>>>> wants to enforce. I do not think that this will come, but imagine a boot 
>>>> entry
>>>> that mandates some security wishes (e.g. do only run on non-shared cores). 
>>>>  
>>>
>>> Can we split the namespace for BOOT_SCRIPT into 'ignore if you don't
>>> know what that is' and 'fail if you don't know what that is'? I'm
>>> completely confused how 'optional' those entries are supposed to be...  
>>
>> Since we do not know if and what future entries will come the current default
>> of failing seems the best approach. We can then add things to pc-bios when
>> necessary.
> 
> That's where I'm coming from: Have some values where unknown entries
> lead to (desired) failure, and others where unknown entries are simply
> ignored. That would give us automatic toleration for optional entries.

Well, this is the first new entry after 14 years of list-directed-ipl so there
is a slight chance to over-engineer here ;-)

In the end this is a field that does not belong to Linux-only, it is also 
defined
by the machine architecture.