ref-manual: add note about license implications of bundled initramfs

Ensure users are aware that usage of INITRAMFS_IMAGE_BUNDLE is only
appropriate for use with GPLv2 compatible software.

(From yocto-docs rev: ecf4582b454aa301905f0f9e3c6f5adb98dc1991)

Signed-off-by: Daniel Wagenknecht <dwagenknecht@emlix.com>
Reviewed-by: Michael Opdenacker <michael.opdenacker@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/documentation/ref-manual/variables.rst b/documentation/ref-manual/variables.rst
index 6cb9ad9c9e..5f6f91146b 100644
--- a/documentation/ref-manual/variables.rst
+++ b/documentation/ref-manual/variables.rst
@@ -3589,6 +3589,12 @@ system and gives an overview of their function and contents.
 
       .. note::
 
+         Bundling the initramfs with the kernel conflates the code in the
+         initramfs with the GPLv2 licensed Linux kernel binary. Thus only GPLv2
+         compatible software may be part of a bundled initramfs.
+
+      .. note::
+
          Using an extra compilation pass to bundle the initramfs avoids a
          circular dependency between the kernel recipe and the initramfs
          recipe should the initramfs include kernel modules. Should that be