treewide: Add SPDX license identifier - Makefile/Kconfig

Add SPDX license identifiers to all Make/Kconfig files which:

- Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

selftests: remove duplicated all and clean target

Currently, kselftest use TEST_PROGS, TEST_PROGS_EXTENDED, TEST_FILES to
indicate the test program, extended test program and test files. It is
easy to understand the purpose of these files. But mix of compiled and
uncompiled files lead to duplicated "all" and "clean" targets.

In order to remove the duplicated targets, introduce TEST_GEN_PROGS,
TEST_GEN_PROGS_EXTENDED, TEST_GEN_FILES to indicate the compiled
objects.

Also, the later patch will make use of TEST_GEN_XXX to redirect these
files to output directory indicated by KBUILD_OUTPUT or O.

And add this changes to "Contributing new tests(details)" of
Documentation/kselftest.txt.

Signed-off-by: Bamvor Jian Zhang <bamvor.zhangjian@linaro.org>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>

selftests/sigaltstack: Add new testcase for sigaltstack(SS_ONSTACK|SS_AUTODISARM)

This patch adds the test case for SS_AUTODISARM flag.
The test-case tries to set SS_AUTODISARM flag and checks if
the nested signal corrupts the stack after swapcontext().

Signed-off-by: Stas Sergeev <stsp@list.ru>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-api@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1460665206-13646-5-git-send-email-stsp@list.ru
Signed-off-by: Ingo Molnar <mingo@kernel.org>