Add recipe for linux kselftest

Kselftest is a set of unit and regression tests under the
tools/testing/selftests/ directory of the Linux kernel. These are used
for testing individual code paths in the kernel.

Kselftest is not debianized and is not available as part of the official
Debian repository.

This patch provides a recipe to build kselftest from the linux source of
your choice.

Sometimes developers/testers tend to use the latest version of selftests
from Linux upstream stable releases for testing and hence the need for a
separate recipe instead of being part of the linux recipe of ISAR.

Some kselftest test cases build are known to break in certain linux
versions, this has to be addressed upstream. Right now kselftest build
succeeds even if atleast one of the testcase case build succeeds.

You can change that by setting KSELFTEST_FORCE_TARGETS=1.

TARGETS, TARGETS_SKIP, FORCE_TARGETS can be set using the appropriate
KSELFTEST_* recipe variable.

Signed-off-by: Vijai Kumar K <Vijaikumar_Kanagarajan@mentor.com>

meta-isar/recipes-kernel/kselftest/kselftest_5.6.13.bb

@@ -0,0 +1,11 @@
+# Kselftest package
+#
+# This software is a part of ISAR.
+# Copyright (c) Mentor Graphics, a Siemens business, 2020
+#
+# SPDX-License-Identifier: MIT
+
+require recipes-kernel/kselftest/kselftest.inc
+
+SRC_URI += "https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-${PV}.tar.xz"
+SRC_URI[sha256sum] = "f125d79c8f6974213638787adcad6b575bbd35a05851802fd83f622ec18ff987"

meta/recipes-kernel/kselftest/files/rules

@@ -0,0 +1,41 @@
+#!/usr/bin/make -f
+
+# Debian rules for Kselftest build
+#
+# This software is a part of ISAR.
+# Copyright (c) Mentor, A Siemens Business
+#
+# SPDX-License-Identifier: MIT
+
+deb_top_dir:=$(CURDIR)/debian
+kselftest_install_dir :=$(deb_top_dir)/kselftest/usr/libexec/kselftest
+export CROSS_COMPILE=$(DEB_HOST_GNU_TYPE)-
+
+ifeq ($(DEB_HOST_GNU_CPU), arm)
+export ARCH=arm
+endif
+ifeq ($(DEB_HOST_GNU_CPU), aarch64)
+export ARCH=arm64
+endif
+ifeq ($(DEB_HOST_GNU_CPU), riscv64)
+export ARCH=riscv
+endif
+ifneq (,$(findstring 86,$(DEB_HOST_GNU_CPU)))
+export ARCH=x86
+endif
+
+PARALLEL_BUILD=-j $(shell echo $$(($$(nproc) * 2)))
+
+override_dh_auto_build:
+	$(MAKE) defconfig
+	$(MAKE) $(PARALLEL_BUILD) -C tools/testing/selftests/ ${KSELFTEST_ARGS}
+
+override_dh_auto_install:
+	mkdir -p ${kselftest_install_dir}
+	cd tools/testing/selftests/ && KSFT_INSTALL_PATH=${kselftest_install_dir} $(MAKE) $(PARALLEL_BUILD) install ${KSELFTEST_ARGS}
+
+override_dh_auto_clean:
+	rm -rf ${deb_top_dir}/kselftest/
+
+%:
+	CFLAGS= LDFLAGS= dh $@ --parallel

meta/recipes-kernel/kselftest/kselftest.inc

@@ -0,0 +1,58 @@
+# Kselftest package for Linux
+#
+# This software is a part of ISAR.
+# Copyright (c) Mentor Graphics, a Siemens Business, 2020
+#
+# SPDX-License-Identifier: MIT
+
+inherit dpkg
+
+FILESEXTRAPATHS_prepend := "${THISDIR}/files:"
+
+# Some test-cases like memfd compilation failed in cross-compilation.
+# Force native compilation for now to have consistent output across
+# ISAR native/cross compilation setups.
+ISAR_CROSS_COMPILE = "0"
+
+DESCRIPTION ?= "Kernel selftests from Linux kernel ${PV}"
+
+DEBIAN_BUILD_DEPENDS ?= " \
+    rsync, \
+    flex,  \
+    bison, \
+    fuse, \
+    libelf-dev:native, \
+    libcap-ng-dev:native, \
+    libpopt-dev:native, \
+    libcap-dev:native, \
+    libmount-dev:native, \
+    libfuse-dev:native, \
+    libmnl-dev:native, \
+    pkg-config, \
+    clang:native, \
+    llvm:native, \
+"
+
+SRC_URI += "file://rules"
+S = "${WORKDIR}/linux-${PV}"
+
+KSELFTEST_TARGETS ?= ""
+KSELFTEST_SKIP_TARGETS ?= ""
+KSELFTEST_FORCE_TARGETS ?= "0"
+
+do_prepare_build[cleandirs] += "${S}/debian"
+do_prepare_build() {
+    deb_debianize
+}
+
+dpkg_runbuild_prepend() {
+    if [ -n "${KSELFTEST_TARGETS}" ];then
+        export KSELFTEST_ARGS="TARGETS=\"${KSELFTEST_TARGETS}\""
+    fi
+    if [ ${KSELFTEST_FORCE_TARGETS} -eq 1 ];then
+        export KSELFTEST_ARGS="${KSELFTEST_ARGS} FORCE_TARGETS=1"
+    fi
+    if [ -n "${KSELFTEST_SKIP_TARGETS}" ];then
+        export KSELFTEST_ARGS="${KSELFTEST_ARGS} SKIP_TARGETS=\"${KSELFTEST_SKIP_TARGETS}\""
+    fi
+}

scripts/ci_build.sh

@@ -166,6 +166,7 @@ cat >>conf/local.conf <<EOF
 ISAR_ENABLE_COMPAT_ARCH_amd64 = "1"
 ISAR_ENABLE_COMPAT_ARCH_arm64 = "1"
 ISAR_ENABLE_COMPAT_ARCH_debian-stretch_amd64 = "0"
+IMAGE_INSTALL += "kselftest"
 EOF
 
 if [ -n "$CROSS_BUILD" ]; then