Re: [PATCH 0/7] hw/kvm: Exit gracefully when KVM is not supported

Philippe Mathieu-Daudé
2021-02-19T13:11:48Z

On 2/19/21 1:18 PM, Daniel P. Berrangé wrote:
> On Fri, Feb 19, 2021 at 01:15:25PM +0100, Philippe Mathieu-Daudé wrote:
>> On 2/19/21 1:00 PM, Daniel P. Berrangé wrote:
>>> On Fri, Feb 19, 2021 at 12:44:21PM +0100, Philippe Mathieu-Daudé wrote:
>>>> Hi,
>>>>
>>>> This series aims to improve user experience by providing
>>>> a better error message when the user tries to enable KVM
>>>> on machines not supporting it.
>>>
>>> Improved error message is good, but it is better if the mgmt apps knows
>>> not to try this in the first place.
>>
>> I am not sure this is the same problem. This series addresses
>> users from the command line (without mgmt app).
>
> Users of mgmt apps can launch the same problematic raspbi + KVM config
> as people who don't use a mgmt app.
>
>>> IOW, I think we want "query-machines" to filter out machines
>>> which are not available with the currently configured accelerator.
>>>
>>> libvirt will probe separately with both TCG and KVM enabled, so if
>>> query-machines can give the right answer in these cases, libvirt
>>> will probably "just work" and not offer to even start such a VM.
>>
>> Yes, agreed. There are other discussions about 'query-machines'
>> and an eventual 'query-accels'. This series doesn't aim to fix
>> the mgmt app problems.
>
> I think this should be fixing query-machines right now. It shouldn't
> be much harder than a single if (...) test in the code.

OK I misunderstood you at first, now I got it. Will include that in v2.