On Thu, 25 May 2017, "Du, Changbin" changbin.du@intel.com wrote:
Hi, Jani, just relized you are in i915 team. :)
+menu "Intel GVT-g graphics virtualization host support"
- depends on DRM_I915
- depends on 64BIT
config DRM_I915_GVT
bool "Enable Intel GVT-g graphics virtualization host support"depends on DRM_I915depends on 64BITdefault nhelp
- bool "Enable Intel GVT-g graphics virtualization host support"
- default n
- depends on DRM_I915_GVT_KVMGT
- help
With this change, you can't actually change this config option. It's purely subject to CONFIG_DRM_I915_GVT_KVMGT. You need to enable KVMGT to even see this option, but enabling it will enable this one too. You can't disable this before you disable KVMGT, but then disabling KVMGT will disable this one too. This config option becomes pointless as a visible option. Which isn't all that bad, considering Documentation/kbuild/kconfig-language.txt:
Jani, this is by design in this patch. We will add another xengt hypervisor glue layer to support XenGT. After that, enable DRM_I915_GVT only if at least one of KVMGT or XENGT enabled or both. Also it doesn't make sense that we only build KVMGT/XenGT module without DRM_I915_GVT.
Such mechanism is not as straigforward as two simple 'choice', so I agree with 'choice' if you prefer it. As you said, it is not a big problem.
Note: select should be used with care. select will force a symbol to a value without visiting the dependencies. By abusing select you are able to select a symbol FOO even if FOO depends on BAR that is not set. In general use select only for non-visible symbols (no prompts anywhere) and for symbols with no dependencies. That will limit the usefulness but on the other hand avoid the illegal configurations all over.
Yes, we should always be carefull with 'select' and should not use it if possible. So here I must create a 'menu' to ensure its safety.
I'm trying to say, why do you make DRM_I915_GVT visible in menuconfig at all when you can't actually change it in menuconfig?
BR, Jani.
BR, Jani.
Choose this option if you want to enable Intel GVT-g graphics virtualization technology host support with integrated graphics. With GVT-g, it's possible to have one integrated graphics@@ -116,13 +119,14 @@ config DRM_I915_GVT
config DRM_I915_GVT_KVMGT tristate "Enable KVM/VFIO support for Intel GVT-g"
- depends on DRM_I915_GVT
- select DRM_I915_GVT depends on KVM depends on VFIO_MDEV && VFIO_MDEV_DEVICE default n help Choose this option if you want to enable KVMGT support for Intel GVT-g.
+endmenu
menu "drm/i915 Debugging" depends on DRM_I915
-- Jani Nikula, Intel Open Source Technology Center _______________________________________________ intel-gvt-dev mailing list intel-gvt-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gvt-dev