Commit c3ff2a5193 ("powerpc/32: add stack protector support")
caused kernel panic on PowerPC when an external module is used with
CONFIG_STACKPROTECTOR because the 'prepare' target was not executed
for the external module build.
Commit e07db28eea ("kbuild: fix single target build for external
module") turned it into a build error because the 'prepare' target is
now executed but the 'prepare0' target is missing for the external
module build.
External module on arm/arm64 with CONFIG_STACKPROTECTOR_PER_TASK is
also broken in the same way.
Move 'PHONY += prepare0' to the common place. GNU Make is fine with
missing rule for phony targets. I also removed the comment which is
wrong irrespective of this commit.
I minimize the change so it can be easily backported to 4.20.x
To fix v4.20, please backport e07db28eea ("kbuild: fix single target
build for external module"), and then this commit.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=201891
Fixes: e07db28eea ("kbuild: fix single target build for external module")
Fixes: c3ff2a5193 ("powerpc/32: add stack protector support")
Fixes: 189af46571 ("ARM: smp: add support for per-task stack canaries")
Fixes: 0a1213fa74 ("arm64: enable per-task stack canaries")
Cc: linux-stable <stable@vger.kernel.org> # v4.20
Reported-by: Samuel Holland <samuel@sholland.org>
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.