[OE-core] [PATCH 1/7] linux-yocto/3.8: allow kernel feature _appends to be overriden

[Bruce Ashfield]

It was pointed out that the current way the KERNEL_FEATURES variable
is appended in the base linux-yocto recipe doesn't allow the appended
features to be prevented in a layer without using python code and
a recipe finalize hook.

To allow easier overriding of 'extra' or 'optional' features that are
defined in the linux-yocto recipe, we create a KERNEL_EXTRA_FEATURES
variable. This variable can be set in a layer to define extra features
or cleared to prevent the recipe's extra features from being appended
to the core functionality.

Signed-off-by: Bruce Ashfield <bruce.ashfield at windriver.com>
---
 meta/recipes-kernel/linux/linux-yocto_3.8.bb |    7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/meta/recipes-kernel/linux/linux-yocto_3.8.bb b/meta/recipes-kernel/linux/linux-yocto_3.8.bb
index b395e45..f29675a 100644
--- a/meta/recipes-kernel/linux/linux-yocto_3.8.bb
+++ b/meta/recipes-kernel/linux/linux-yocto_3.8.bb
@@ -23,8 +23,7 @@ KMETA = "meta"
 COMPATIBLE_MACHINE = "qemuarm|qemux86|qemuppc|qemumips|qemux86-64"
 
 # Functionality flags
-KERNEL_FEATURES_append = " features/netfilter/netfilter.scc"
-KERNEL_FEATURES_append_qemux86=" cfg/sound.scc"
-KERNEL_FEATURES_append_qemux86-64=" cfg/sound.scc"
-KERNEL_FEATURES_append_qemux86=" cfg/paravirt_kvm.scc"
+KERNEL_EXTRA_FEATURES ?= "features/netfilter/netfilter.scc"
+KERNEL_FEATURES_append_qemux86=" ${KERNEL_EXTRA_FEATURES} cfg/sound.scc cfg/paravirt_kvm.scc"
+KERNEL_FEATURES_append_qemux86-64=" ${KERNEL_EXTRA_FEATURES} cfg/sound.scc"
 KERNEL_FEATURES_append = " ${@bb.utils.contains("TUNE_FEATURES", "mx32", " cfg/x32.scc", "" ,d)}"
-- 
1.7.10.4