Re: [Qemu-devel] [PATCH] xen: Restrict build to x86 targets

[Jan Kiszka <jan.kiszka@siemens.com>]

Am 29.11.2010 15:15, Alexander Graf wrote:
> 
> On 29.11.2010, at 13:44, Jan Kiszka wrote:
> 
>> Am 29.11.2010 13:40, Alexander Graf wrote:
>>>
>>> On 29.11.2010, at 13:30, Jan Kiszka wrote:
>>>
>>>> Am 29.11.2010 13:24, Alexander Graf wrote:
>>>>>
>>>>> On 28.11.2010, at 16:59, Jan Kiszka wrote:
>>>>>
>>>>>> From: Jan Kiszka <jan.kiszka@siemens.com>
>>>>>>
>>>>>> Xen target bits in qemu are intended for x86. Let the build system
>>>>>> reflect this and avoid useless building/linking for other targets.
>>>>>
>>>>> Not sure I understand the split. Xen is x86 only, yes. But why split it into host and target? Target usually defines the guest. The piece you marked as _HOST are target specific.
>>>>
>>>> At least so far, the HOST part is build once for all targets into the
>>>> host backend library. As this step injected CONFIG_XEN into all target
>>>> builds, even non-x86 targets built xen_machine_pv and xen_domainbuild.
>>>> That's addressed by the patch.
>>>
>>> I still don't understand the need for that split.
>>
>> Enable Xen and build some non-x86 targets, then you see the need.
>>
>>> The device drivers should be built only once, as do the xen_machine_pv parts. Both are useless on non-x86. CONFIG_XEN should simply always be a target specific option.
>>
>> Maybe the split-up between the "generic" host-side interfaces and
>> xen_machine_pv/xen_domainbuild is the problem. You know the dependencies
>> better than me, maybe you find a better fix.
> 
> Should be enough to just replace obj-$(CONFIG_XEN) by obj-i386-$(CONFIG_XEN).

Indeed (as long as qemu's xen remains x86-only).

> Unless it's very urgent, please wait with this patch until qemu-dm and xenner are in. It's pretty suboptimal to have 3 patches flying around that hit the exact same code spot :).

It isn't urgent. If patches series refactor the stuff and fix the
dependency, I'm happy to wait for them.

Jan

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