original_kernel

source code of Linux source code

Go to file

Nathan Chancellor ff8acf9290 arm64: futex: Restore oldval initialization to work around buggy compilers Commit `045afc2412` ("arm64: futex: Fix FUTEX_WAKE_OP atomic ops with non-zero result value") removed oldval's zero initialization in arch_futex_atomic_op_inuser because it is not necessary. Unfortunately, Android's arm64 GCC 4.9.4 [1] does not agree: ../kernel/futex.c: In function 'do_futex': ../kernel/futex.c:1658:17: warning: 'oldval' may be used uninitialized in this function [-Wmaybe-uninitialized] return oldval == cmparg; ^ In file included from ../kernel/futex.c:73:0: ../arch/arm64/include/asm/futex.h:53:6: note: 'oldval' was declared here int oldval, ret, tmp; ^ GCC fails to follow that when ret is non-zero, futex_atomic_op_inuser returns right away, avoiding the uninitialized use that it claims. Restoring the zero initialization works around this issue. [1]: https://android.googlesource.com/platform/prebuilts/gcc/linux-x86/aarch64/aarch64-linux-android-4.9/ Cc: stable@vger.kernel.org Fixes: `045afc2412` ("arm64: futex: Fix FUTEX_WAKE_OP atomic ops with non-zero result value") Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>		2019-04-18 18:17:08 +01:00
Documentation	…
LICENSES	…
arch	arm64: futex: Restore oldval initialization to work around buggy compilers	2019-04-18 18:17:08 +01:00
block	…
certs	…
crypto	…
drivers	…
fs	Merge branch 'page-refs' (page ref overflow)	2019-04-14 15:09:40 -07:00
include	Merge branch 'page-refs' (page ref overflow)	2019-04-14 15:09:40 -07:00
init	…
ipc	…
kernel	Merge branch 'page-refs' (page ref overflow)	2019-04-14 15:09:40 -07:00
lib	…
mm	Merge branch 'page-refs' (page ref overflow)	2019-04-14 15:09:40 -07:00
net	…
samples	…
scripts	…
security	…
sound	…
tools	…
usr	…
virt	…
.clang-format	…
.cocciconfig	…
.get_maintainer.ignore	…
.gitattributes	…
.gitignore	…
.mailmap	…
COPYING	…
CREDITS	…
Kbuild	…
Kconfig	…
MAINTAINERS	…
Makefile	Linux 5.1-rc5	2019-04-14 15:17:41 -07:00
README	…

README

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.