On Thu, 02 Feb 2017 20:50:48 +1100 Michael Ellerman <mpe@xxxxxxxxxxxxxx> wrote: > Michael Ellerman <mpe@xxxxxxxxxxxxxx> writes: > > > Currently the kconfig logic for VFIO_IOMMU_SPAPR_TCE and VFIO_SPAPR_EEH > > is broken when SPAPR_TCE_IOMMU=n. Leading to: > > > > warning: (VFIO) selects VFIO_IOMMU_SPAPR_TCE which has unmet direct dependencies (VFIO && SPAPR_TCE_IOMMU) > > warning: (VFIO) selects VFIO_IOMMU_SPAPR_TCE which has unmet direct dependencies (VFIO && SPAPR_TCE_IOMMU) > > drivers/vfio/vfio_iommu_spapr_tce.c:113:8: error: implicit declaration of function 'mm_iommu_find' > > > > This stems from the fact that VFIO selects VFIO_IOMMU_SPAPR_TCE, and > > although it has an if clause, the condition is not correct. > > > > We could fix it by doing select VFIO_IOMMU_SPAPR_TCE if SPAPR_TCE_IOMMU, > > but the cleaner fix is to drop the selects and tie VFIO_IOMMU_SPAPR_TCE > > to the value of VFIO, and express the dependencies in only once place. > > > > Do the same for VFIO_SPAPR_EEH. > > > > The end result is that the values of VFIO_IOMMU_SPAPR_TCE and > > VFIO_SPAPR_EEH follow the value of VFIO, except when SPAPR_TCE_IOMMU=n > > and/or EEH=n. Which is exactly what we want to happen. > > Ping? > > There was a bit of discussion on this patch but I think we decided it > was correct in the end. If there are no other comments or objections, I'll queue this for v4.11. Based on this last comment: eg, using def_tristate you get: # CONFIG_VFIO_IOMMU_SPAPR_TCE is not set # CONFIG_VFIO is not set Whereas using depends all you get is: # CONFIG_VFIO is not set I prefer prefer the solution here that doesn't leave extra unselected config entries when CONFIG_VFIO is also not selected. Thanks, Alex
