Re: [PATCH] vfio: Fix build break when SPAPR_TCE_IOMMU=n

From: Michael Ellerman
Date: Mon Nov 07 2016 - 03:36:05 EST


Paolo Bonzini <pbonzini@xxxxxxxxxx> writes:
> On 04/11/2016 06:48, Michael Ellerman wrote:
>> diff --git a/drivers/vfio/Kconfig b/drivers/vfio/Kconfig
>> index da6e2ce77495..6b51a4ebed8a 100644
>> --- a/drivers/vfio/Kconfig
>> +++ b/drivers/vfio/Kconfig
>> @@ -6,12 +6,12 @@ config VFIO_IOMMU_TYPE1
>> config VFIO_IOMMU_SPAPR_TCE
>> tristate
>> depends on VFIO && SPAPR_TCE_IOMMU
>> - default n
>> + default VFIO
>
> No need to depend on VFIO since you already have it in "default".

True, I can take that out.

> (I assume you cannot use "default y" because "depends on" doesn't downgrade
> "y" to "m" when VFIO is a module.

Correct.

> A shorthand is
>
> def_tristate VFIO && SPAPR_TCE_IOMMU

Yep. My experience though is that a lot of folks don't really know what
that means. So I prefer to spell it out with an explicit type, depends
and default.

But I'll respin it that way if Alex prefers the shorter style.

cheers