Re: [OE-core] [PATCH v3 09/11] image_types_wic.bbclass: capture verbose wic output by default

Trevor Woerner
2025-04-14T20:44:08Z

On Fri 2025-04-04 @ 07:29:30 PM, Mikko Rapeli via lists.openembedded.org wrote:
> Call wic with --debug to capture logs from wic internals
> so that it's clear which partitions get created and which
> files get copied where. wic plugins contain for example
> race conditions which don't install files at all and thus
> images fail to boot and it's not possible to debug these without
> something in wic task logs.
>
> For example core-image-initramfs-boot do_image_wic
> log is now 576 lines which is not excessive but very
> important when debugging problems, especially race
> conditions which are only hit in some builds in CI.
>
> Signed-off-by: Mikko Rapeli <mikko.rapeli@linaro.org>
> ---
> meta/classes-recipe/image_types_wic.bbclass | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/meta/classes-recipe/image_types_wic.bbclass b/meta/classes-recipe/image_types_wic.bbclass
> index 1b422b6280..10888bc12b 100644
> --- a/meta/classes-recipe/image_types_wic.bbclass
> +++ b/meta/classes-recipe/image_types_wic.bbclass
> @@ -72,7 +72,7 @@ IMAGE_CMD:wic () {
> if [ -z "$wks" ]; then
> bbfatal "No kickstart files from WKS_FILES were found: ${WKS_FILES}. Please set WKS_FILE or WKS_FILES appropriately."
> fi
> - BUILDDIR="${TOPDIR}" PSEUDO_UNLOAD=1 wic create "$wks" --vars "${STAGING_DIR}/${MACHINE}/imgdata/" -e "${IMAGE_BASENAME}" -o "$build_wic/" -w "$tmp_wic" ${WIC_CREATE_EXTRA_ARGS}
> + BUILDDIR="${TOPDIR}" PSEUDO_UNLOAD=1 wic create --debug "$wks" --vars "${STAGING_DIR}/${MACHINE}/imgdata/" -e "${IMAGE_BASENAME}" -o "$build_wic/" -w "$tmp_wic" ${WIC_CREATE_EXTRA_ARGS}
>
> # look to see if the user specifies a custom imager
> IMAGER=direct

When I need to debug a wic issue, I add "--debug" to WIC_CREATE_EXTRA_ARGS in
my conf/local.conf, debug the issue, then submit the patch which modifies the
layer without any debugging remnants left behind. I can then either leave wic
debugging turned on, or turn it off for my builds as I see fit. Turning on
debugging by default for everyone using wic is not what we should be doing.
It will slow down builds, and will inflate log files... by miniscule amounts,
sure, but not the direction we should be taking.

If you feel there are messages that should be logged on every wic invocation
(on which I doubt there will be consensus) then they should be moved out from
behind a --debug flag. The whole point of a debug flag is to identify messages
that do not need to be logged on every build, but only under special
circumstances. Lots of software projects have debug flags; I can't think of any
that turn their debug flags on by default.