[yocto] swupate.bblcass dependencies not triggering rebuild

[Andreas Fenkart]

Hi list,

I want to create a swupdate file, which is a cpio file with rootfs and
some metadata to control software update. My problem is, that it is not
rebuilt everytime the rootfs changes. I checked in the cooker log.

NOTE: recipe swupdate-image-1.0-r4: task do_populate_sysroot_setscene: Succeeded
NOTE: Running noexec task 5475 of 5478 (ID: 27,
meta-devel/recipes-core/images/swupdate-image.bb, do_build)

I generated the dot files with bitbake -g swupdate, and while do_swuimage
has to run before do_build, do_build does not depend directly on do_swuimage:

swupdate-image.do_createlink -> swupdate-image.do_swuimage
swupdate-image.do_install -> swupdate-image.do_createlink
swupdate-image.do_populate_sysroot -> swupdate-image.do_install
swupdate-image.do_build" -> swupdate-image.do_populate_sysroot

$ bitbake-diffsigs -t swupdate-image do_build
ERROR: No sigdata files found matching swupdate-image do_build

$ bitbake-diffsigs -t swupdate-image do_populate_sysroot
Unable to find matching sigdata for ....
recipes-core/images/swupdate-image.bb.do_install with hashes
c0bc8039e8dbe8d70939dd3db2ceb922 or e9d7b242613f323d4d6adff3d6d4881b

$ bitbake-diffsigs -t swupdate-image do_install
ERROR: No sigdata files found matching swupdate-image do_install

$ bitbake-diffsigs -t swupdate-image do_createlink
Hash for dependent task imagesswupdate-image.bb.do_swuimage changed
from cec64d7e21b0375ff641427d5d631254 to
45510576a402839f4c4d4ac9b9eff578
  Hash for dependent task imagesrootfs.bb.do_build changed from
876eb436b444f84efd355c0294b871bf to fabbabdd000427cdf5e721b59784d5c4
  Unable to find matching sigdata for
meta-devel/recipes-core/images/rootfs.bb.do_build with hashes
876eb436b444f84efd355c0294b871bf or fabbabdd000427cdf5e721b59784d5c4

The dependency on rootfs is added here:
https://github.com/sbabic/meta-swupdate/blob/master/classes/swupdate.bbclass#L64
with IMAGE_DEPENDS="rootfs"

Is it correct to 'depend' on :do_build? It seems rather uncommon.

I checked the latest swupdate-image.do_populate siginfo in sstate, which is
pretty large, so adding just the task-dependencies:
..
Tasks this task depends on:
['..-devel/recipes-core/images/swupdate-image.bb.do_install']
This task depends on the checksums of files: []
Hash for dependent task
./meta-devel/recipes-core/images/swupdate-image.bb.do_install is
e9d7b242613f323d4d6adff3d6d4881b
Computed Hash is d8b1d389351c25e0c4a519fb8fe9ddda
..

Which makes me wonder, since bitbake-diffsig said do_install has no sigdata

I must admit that I feel pretty lost here.

/Andreas