Re: [Xen-devel] Upping gcc requirement for x86

[George Dunlap <dunlapg@xxxxxxxxx>]

On Fri, Mar 30, 2018 at 5:11 PM, Doug Goldstein <cardoe@xxxxxxxxxx> wrote:
> On 3/30/18 3:50 AM, George Dunlap wrote:
>> On Thu, Mar 29, 2018 at 6:47 PM, Doug Goldstein <cardoe@xxxxxxxxxx> wrote:
>>> On 3/29/18 12:05 PM, George Dunlap wrote:
>>>> On Thu, Mar 29, 2018 at 4:45 PM, Wei Liu <wei.liu2@xxxxxxxxxx> wrote:
>>>>
>>>> Long term I think we want to get away from building seabios ourselves
>>>> altogether; but it's a bit late in the release cycle to work out that
>>>> kind of change.
>>>>
>>>> On the whole I'd probably go with #3 at this point.
>>>>
>>>>  -George
>>>>
>>>
>>> Violent agreement here. Every distro wants to see this so they can share
>>> these blobs. Its what lead to the change to tracking tags in
>>> 3dd926a25d866364ce6d46c21f9ac05a82fa7ffb originally.
>>
>> I don't understand what you mean -- AFAIK there's no *dependency* from
>> Xen to any particular version of SeaBIOS (unlike QEMU).  If 1.9 won't
>> compile with gcc 4.4, but 1.8 does, we can just point the tag to 4.4.
>> Distros will be compiling their own SeaBIOS versions anyway, no?
>>
>> Or am I missing your point somehow?
>>
>>  -George
>>
>
> My point was we explicitly moved to testing/shipping tags so that we
> distros could say "oh this is what the Xen folks tested with I have
> confidence that if we ship the same version it should work for users".
>
> I think we want to get away from building it ourselves and defaulting to
> telling distros they need to provide it.

Those seem like sort of contradictory goals to me, particularly if the
goal of a distro is to share seabios between KVM and Xen.

FWIW for the CentOS Virt SIG, I
* build seabios separately
* Only update when the version in "CentOS core" (i.e., RHEL) is larger
than the version I've built
* Then just pull the latest package from Fedora.

The only reason I build a separate one at all is that the one in
"CentOS Core" seems to have some KVM-focused patches which break it
under Xen.  In an ideal world I would get that fixed and just use the
seabios from the base version of the OS -- the same as I would any
other library.

If we want distros to build their own version of seabios, we should
also decouple the expectation that a given version of Xen matches (or
needs to match) a given version of seabios.

AFAIK this decoupling has already taken place, it's just that nobody
knows about it.  seabios-master has been tested with Xen for ages, so
all versions of seabios released in the last several years should Just
Work.

That's why I said to downgrade to 1.8 in our builder -- because I
expected distros to ignore that value and use 1.10 or whatever the
newest version is anyway.

Are you aware of any seabios / Xen dependencies -- particular versions
of vanilla seabios that don't work with particular versions of Xen?

 -George

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel