Re: [Qemu-trivial] [Qemu-devel] [PATCH 1/4] Replace '-machine accel=xyz' with '-accel xyz'

[Thomas Huth]

On 13.06.2018 15:54, Paolo Bonzini wrote:
> On 13/06/2018 14:53, Thomas Huth wrote:
>> On 13.06.2018 14:48, Paolo Bonzini wrote:
>>> On 13/06/2018 07:05, Thomas Huth wrote:
>>>> diff --git a/tests/vmgenid-test.c b/tests/vmgenid-test.c
>>>> index 8d915c6..4324034 100644
>>>> --- a/tests/vmgenid-test.c
>>>> +++ b/tests/vmgenid-test.c
>>>> @@ -131,7 +131,7 @@ static void read_guid_from_monitor(QemuUUID *guid)
>>>>  static char disk[] = "tests/vmgenid-test-disk-XXXXXX";
>>>>  
>>>>  #define GUID_CMD(guid)                          \
>>>> -    "-machine accel=kvm:tcg "                   \
>>>> +    "-accel kvm:tcg "                           \
>>>>      "-device vmgenid,id=testvgid,guid=%s "      \
>>>
>>> "-accel kvm:tcg" works, but it really shouldn't (and I think we can
>>> change it without a deprecation period).   The right syntax would be
>>> "-accel kvm -accel tcg", so that you can specify options that are valid
>>> only for KVM, or onlty for TCG.
>>
>> I see your point, but this would break these qtests that are trying to
>> override the "-machine accel=qtest" from libqtest.c this way...
> 
> The solution would be to put "-accel kvm -accel tcg" before "-accel qtest".
> 
>> and if
>> any other tool out there in the wild is already depending on this
>> behavior, too, we can not change it so easily anymore.
> 
> I think -accel is new and obscure enough that it's unlikely to be used
> with a colon.  In my opinion, the risk is worth the benefit of finally
> getting a proper interface for accelerators.

I agree with you. Let's try to get this right before it's too late!

 Thomas