[PATCH v2] meta: fix generation of kernel CONFIG_ in SPDX3

[Benjamin Robin <benjamin.robin@bootlin.com>]

With the current solution, using a separate task
(do_create_kernel_config_spdx) there is a dependency issue. Sometimes
the final rootfs SBOM does not contain the CONFIG_ values.

do_create_kernel_config_spdx is executed after do_create_spdx which
deploys the SPDX file. do_create_kernel_config_spdx calls
oe.sbom30.find_root_obj_in_jsonld to read from the deploy directory,
which is OK, but the do_create_kernel_config_spdx ends up writing to
this deployed file (updating it).

do_create_rootfs_spdx has an explicit dependency to all do_create_spdx
tasks, but there is nothing that prevents executing
do_create_kernel_config_spdx after do_create_rootfs_spdx.

To fix it, instead, now read from the workdir, and write to the
workdir, and do the processing from the do_create_spdx task:
we append to the do_create_spdx task.
Furthermore, update oeqa selftest to execute do_create_spdx instead
of removed function.

Also only execute this task if create-spdx-3.0 was inherited,
previously this code could be executed if create-spdx-2.2 is
inherited.

Fixes: 228a968e7c47 ("kernel.bbclass: Add task to export kernel configuration to SPDX")
Signed-off-by: Benjamin Robin (Schneider Electric) <benjamin.robin@bootlin.com>
---
Changes in v2:
- Update spdx oeqa selftest
- Link to v1: https://lore.kernel.org/r/20260213-fix-kernel-config-spdx-v1-1-4fd66ca5cb5d@bootlin.com
---
 meta/classes-recipe/kernel.bbclass   | 22 ++++++++++------------
 meta/lib/oeqa/selftest/cases/spdx.py |  2 +-
 2 files changed, 11 insertions(+), 13 deletions(-)

diff --git a/meta/classes-recipe/kernel.bbclass b/meta/classes-recipe/kernel.bbclass
index f989b31c477c..ce43f6c13036 100644
--- a/meta/classes-recipe/kernel.bbclass
+++ b/meta/classes-recipe/kernel.bbclass
@@ -864,13 +864,9 @@ addtask deploy after do_populate_sysroot do_packagedata
 
 EXPORT_FUNCTIONS do_deploy
 
-python __anonymous() {
-    inherits = (d.getVar("INHERIT") or "")
-    if "create-spdx" in inherits:
-        bb.build.addtask('do_create_kernel_config_spdx', 'do_populate_lic do_deploy', 'do_create_spdx', d)
-}
-
-python do_create_kernel_config_spdx() {
+do_create_spdx:append() {
+    if not bb.data.inherits_class("create-spdx-3.0", d):
+        return
     if d.getVar("SPDX_INCLUDE_KERNEL_CONFIG", True) == "1":
         import oe.spdx30
         import oe.spdx30_tasks
@@ -903,9 +899,11 @@ python do_create_kernel_config_spdx() {
         except Exception as e:
             bb.error(f"Failed to parse kernel config file: {e}")
 
-        build, build_objset = oe.sbom30.find_root_obj_in_jsonld(
-            d, "recipes", f"recipe-{pn}", oe.spdx30.build_Build
-        )
+        path = oe.sbom30.jsonld_arch_path(d, pkg_arch, "recipes", f"recipe-{pn}", deploydir=deploydir)
+        build_objset = oe.sbom30.load_jsonld(d, path, required=True)
+        build = build_objset.find_root(oe.spdx30.build_Build)
+        if not build:
+            bb.fatal("No root %s found in %s" % (oe.spdx30.build_Build.__name__, path))
 
         kernel_build = build_objset.add_root(
             oe.spdx30.build_Build(
@@ -924,9 +922,9 @@ python do_create_kernel_config_spdx() {
             [kernel_build]
         )
 
-        oe.sbom30.write_jsonld_doc(d, build_objset, deploydir / pkg_arch / "recipes" / f"recipe-{pn}.spdx.json")
+        oe.sbom30.write_jsonld_doc(d, build_objset, path)
 }
-do_create_kernel_config_spdx[depends] = "virtual/kernel:do_configure"
+do_create_spdx[depends] += "virtual/kernel:do_configure"
 
 # Add using Device Tree support
 inherit kernel-devicetree
diff --git a/meta/lib/oeqa/selftest/cases/spdx.py b/meta/lib/oeqa/selftest/cases/spdx.py
index 41ef52fce1ca..5830d7c0872a 100644
--- a/meta/lib/oeqa/selftest/cases/spdx.py
+++ b/meta/lib/oeqa/selftest/cases/spdx.py
@@ -369,7 +369,7 @@ class SPDX30Check(SPDX3CheckBase, OESelftestTestCase):
         objset = self.check_recipe_spdx(
             kernel_recipe,
             spdx_path,
-            task="do_create_kernel_config_spdx",
+            task="do_create_spdx",
             extraconf="""\
                 INHERIT += "create-spdx"
                 SPDX_INCLUDE_KERNEL_CONFIG = "1"

---
base-commit: 3a8f0075d52cb653118774baa03aa8d5231f943c
change-id: 20260213-fix-kernel-config-spdx-99223936e69f

Best regards,
-- 
Benjamin Robin (Schneider Electric) <benjamin.robin@bootlin.com>