wic builds an empty rootfs on second image build with rm_work enabled

[Mikko Rapeli <mikko.rapeli@linaro.org>]

Hi,

After image build completes, rootfs directory is wiped by rm_work_rootfs.

If the image recipe is built again without clean, for example when
TESTIMAGE_AUTO is enabled to run tests, then rootfs task will not
run and thus wic uses an empty rootfs directory to populate the rootfs which
of course then fails at runtime.

How to fix this?

I know RP doesn't like rm_work, but I really need it. I can't leave all
builds laying around and bitbake IPC setup fails if a lot of IO is wiping
build/tpm's while recipe parsing is happening (the famous 30 second timeout).

wic image related tasks could possible depend on do_rootfs instead of
do_image_complete but seems to break the whole do_image_complete design.

Should rm_work_rootfs be moved from after do_image_complete to after do_image_wic
if wic images are used?

Or should users just remember to "bitbake -c clean image && bitbake image" if things
fail?

There are some other issues with testimage.bbclass and leaking cooker processes
which confused me for a long time but I'll try to send patches for those.

Cheers,

-Mikko