docs: kselftest: Document the FORCE_TARGETS build variable

FORCE_TARGETS has been part of the kselftest build system for
some time but is absent from the developer documentation. Without
an entry here, users relying on kselftest in CI pipelines would
have to read the selftests Makefile directly to discover the
option.

A build that exits zero despite some targets failing can mask
real breakage and mislead automated systems into reporting
success. Add a dedicated section so that CI authors can easily
find and adopt FORCE_TARGETS=1 to turn such silent partial
failures into hard errors.

Link: https://lore.kernel.org/r/20260417-selftests-docs-v1-1-32e4a78214eb@suse.com
Signed-off-by: Ricardo B. Marlière <rbm@suse.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

diff --git a/Documentation/dev-tools/kselftest.rst b/Documentation/dev-tools/kselftest.rst
index 18c2da67fae424788087906ae7b81b0f7844d29f..d7bfe320338ce264ee42a634875597ddadb4ff0b 100644 (file)
--- a/Documentation/dev-tools/kselftest.rst
+++ b/Documentation/dev-tools/kselftest.rst
@@ -126,6 +126,18 @@ dedicated skiplist::
 See the top-level tools/testing/selftests/Makefile for the list of all
 possible targets.
 
+Requiring all targets to build successfully
+===========================================
+
+By default, the build succeeds as long as at least one target builds
+without error. Set ``FORCE_TARGETS=1`` to instead require every target to
+build successfully; make will abort as soon as any target fails::
+
+  $ make -C tools/testing/selftests FORCE_TARGETS=1
+
+This applies to both the ``all`` and ``install`` targets and is useful in
+CI environments where a silent partial build would be misleading.
+
 Running the full range hotplug selftests
 ========================================