[libvirt] [PATCH 1/5] S390: Override QEMU_CAPS_NO_ACPI for s390x

[Viktor Mihajlovski]

On 06/22/2012 11:59 AM, Daniel P. Berrange wrote:
> On Fri, Jun 22, 2012 at 09:50:25AM +0200, Michal Privoznik wrote:
>> On 21.06.2012 18:15, Viktor Mihajlovski wrote:
>>>
>>> Starting a KVM guest on s390 fails immediately. This is because
>>> "qemu --help" reports -no-acpi even for the s390(x) architecture but
>>> -no-acpi isn't supported there.
>>> Workaround is to remove QEMU_CAPS_NO_ACPI from the capability set
>>> after the version/capability extraction.
>>>
>>> Signed-off-by: Viktor Mihajlovski<mihajlov at linux.vnet.ibm.com>
>>> ---
>>>   src/qemu/qemu_capabilities.c |    5 +++++
>>>   1 files changed, 5 insertions(+), 0 deletions(-)
>>>
>>> diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c
>>> index 4308833..0c01cb0 100644
>>> --- a/src/qemu/qemu_capabilities.c
>>> +++ b/src/qemu/qemu_capabilities.c
>>> @@ -1511,6 +1511,11 @@ int qemuCapsExtractVersionInfo(const char *qemu, const char *arch,
>>>           qemuCapsSet(flags, QEMU_CAPS_PCI_MULTIBUS);
>>>       }
>>>
>>> +    /* S390 and probably other archs do not support no-acpi -
>>> +       maybe the qemu option parsing should be re-thought. */
>>> +    if (STREQLEN(arch, "s390x", 5))
>>> +        qemuCapsClear(flags, QEMU_CAPS_NO_ACPI);
>>> +
>>>       /* qemuCapsExtractDeviceStr will only set additional flags if qemu
>>>        * understands the 0.13.0+ notion of "-device driver,".  */
>>>       if (qemuCapsGet(flags, QEMU_CAPS_DEVICE)&&
>>>
>>
>> I don't think this is the right approach. I mean, if qemu's broken
>> shouldn't it be fixed?
>
> In principal I agree with you, but this aspect of QEMU is not likely
> to be changed in the forseeable future, not least because QEMU don't
> like us using -help in the first place.
>
> So, ACK to this patch on that basis
>
> Daniel

actually, the newest upstream version has removed the -no-acpi option 
for non-x86 archs. Still it is probably prudent to keep this workaround 
to support older qemu versions. Thanks.

-- 

Mit freundlichen Grüßen/Kind Regards
    Viktor Mihajlovski

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