ktest: Add test type make_min_config

After doing a make localyesconfig, your kernel configuration may
not be the most useful minimum configuration. Having a true minimum
config that you can use against other configs is very useful if
someone else has a config that breaks on your code. By only forcing
those configurations that are truly required to boot your machine
will give you less of a chance that one of your set configurations
will make the bug go away. This will give you a better chance to
be able to reproduce the reported bug matching the broken config.

Note, this does take some time, and may require you to run the
test over night, or perhaps over the weekend. But it also allows
you to interrupt it, and gives you the current minimum config
that was found till that time.

Note, this test automatically assumes a BUILD_TYPE of oldconfig
and its test type acts like boot.

TODO: add a test version that makes the config do more than just
      boot, like having network access.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 50 insertions, 0 deletions

diff --git a/tools/testing/ktest/sample.conf b/tools/testing/ktest/sample.conf
index 82c966c32d61..a83846d829bd 100644
--- a/tools/testing/ktest/sample.conf
+++ b/tools/testing/ktest/sample.conf
@@ -814,3 +814,53 @@
 #   MIN_CONFIG = /home/test/config-min
 #   BISECT_MANUAL = 1
 #
+#
+#
+# For TEST_TYPE = make_min_config
+#
+#  After doing a make localyesconfig, your kernel configuration may
+#  not be the most useful minimum configuration. Having a true minimum
+#  config that you can use against other configs is very useful if
+#  someone else has a config that breaks on your code. By only forcing
+#  those configurations that are truly required to boot your machine
+#  will give you less of a chance that one of your set configurations
+#  will make the bug go away. This will give you a better chance to
+#  be able to reproduce the reported bug matching the broken config.
+#
+#  Note, this does take some time, and may require you to run the
+#  test over night, or perhaps over the weekend. But it also allows
+#  you to interrupt it, and gives you the current minimum config
+#  that was found till that time.
+#
+#  Note, this test automatically assumes a BUILD_TYPE of oldconfig
+#  and its test type acts like boot.
+#  TODO: add a test version that makes the config do more than just
+#   boot, like having network access.
+#
+#  OUTPUT_MIN_CONFIG is the path and filename of the file that will
+#   be created from the MIN_CONFIG. If you interrupt the test, set
+#   this file as your new min config, and use it to continue the test.
+#   This file does not need to exist on start of test.
+#   This file is not created until a config is found that can be removed.
+#   (required field)
+#
+#  START_MIN_CONFIG is the config to use to start the test with.
+#   you can set this as the same OUTPUT_MIN_CONFIG, but if you do
+#   the OUTPUT_MIN_CONFIG file must exist.
+#   (default MIN_CONFIG)
+#
+#  IGNORE_CONFIG is used to specify a config file that has configs that
+#   you already know must be set. Configs are written here that have
+#   been tested and proved to be required. It is best to define this
+#   file if you intend on interrupting the test and running it where
+#   it left off. New configs that it finds will be written to this file
+#   and will not be tested again in later runs.
+#   (optional)
+#
+# Example:
+#
+#  TEST_TYPE = make_min_config
+#  OUTPUT_MIN_CONFIG = /path/to/config-new-min
+#  START_MIN_CONFIG = /path/to/config-min
+#  IGNORE_CONFIG = /path/to/config-tested
+#