linux-stable.git/arch/arm64/kernel/vdso32, branch linux-5.4.y

arm64: vdso32: suppress error message for 'make mrproper'

2021-11-26T09:47:21+00:00

commit 14831fad73f5ac30ac61760487d95a538e6ab3cb upstream.

When running the following command without arm-linux-gnueabi-gcc in
one's $PATH, the following warning is observed:

$ ARCH=arm64 CROSS_COMPILE_COMPAT=arm-linux-gnueabi- make -j72 LLVM=1 mrproper
make[1]: arm-linux-gnueabi-gcc: No such file or directory

This is because KCONFIG is not run for mrproper, so CONFIG_CC_IS_CLANG
is not set, and we end up eagerly evaluating various variables that try
to invoke CC_COMPAT.

This is a similar problem to what was observed in
commit dc960bfeedb0 ("h8300: suppress error messages for 'make clean'")

Reported-by: Lucas Henneman 
Suggested-by: Masahiro Yamada 
Signed-off-by: Nick Desaulniers 
Reviewed-by: Vincenzo Frascino 
Reviewed-by: Nathan Chancellor 
Tested-by: Nathan Chancellor 
Link: https://lore.kernel.org/r/20211019223646.1146945-4-ndesaulniers@google.com
Signed-off-by: Will Deacon 
Signed-off-by: Greg Kroah-Hartman

ARM64: vdso32: Install vdso32 from vdso_install

2020-08-26T08:41:05+00:00

[ Upstream commit 8d75785a814241587802655cc33e384230744f0c ]

Add the 32-bit vdso Makefile to the vdso_install rule so that 'make
vdso_install' installs the 32-bit compat vdso when it is compiled.

Fixes: a7f71a2c8903 ("arm64: compat: Add vDSO")
Signed-off-by: Stephen Boyd 
Reviewed-by: Vincenzo Frascino 
Acked-by: Will Deacon 
Cc: Vincenzo Frascino 
Link: https://lore.kernel.org/r/20200818014950.42492-1-swboyd@chromium.org
Signed-off-by: Catalin Marinas 
Signed-off-by: Sasha Levin

arm64: vdso32: Rename COMPATCC to CC_COMPAT

2019-10-07T12:32:13+00:00

For consistency with CROSS_COMPILE_COMPAT, mechanically rename COMPATCC
to CC_COMPAT so that specifying aspects of the compat vDSO toolchain in
the environment isn't needlessly confusing.

Acked-by: Catalin Marinas 
Signed-off-by: Will Deacon

arm64: vdso32: Pass '--target' option to clang via VDSO_CAFLAGS

2019-10-07T12:32:09+00:00

Directly passing the '--target' option to clang by appending to
COMPATCC does not work if COMPATCC has been specified explicitly as
an argument to Make unless the 'override' directive is used, which is
ugly and different to what is done in the top-level Makefile.

Move the '--target' option for clang out of COMPATCC and into
VDSO_CAFLAGS, where it will be picked up when compiling and assembling
the 32-bit vDSO under clang.

Reported-by: Catalin Marinas 
Acked-by: Catalin Marinas 
Signed-off-by: Will Deacon

arm64: vdso32: Don't use KBUILD_CPPFLAGS unconditionally

2019-10-07T12:32:05+00:00

KBUILD_CPPFLAGS is defined differently depending on whether the main
compiler is clang or not. This means that it is not possible to build
the compat vDSO with GCC if the rest of the kernel is built with clang.

Define VDSO_CPPFLAGS directly to break this dependency and allow a clang
kernel to build a compat vDSO with GCC:

  $ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- \
    CROSS_COMPILE_COMPAT=arm-linux-gnueabihf- CC=clang \
    COMPATCC=arm-linux-gnueabihf-gcc

Acked-by: Catalin Marinas 
Signed-off-by: Will Deacon

arm64: vdso32: Move definition of COMPATCC into vdso32/Makefile

2019-10-07T12:32:02+00:00

There's no need to export COMPATCC, so just define it locally in the
vdso32/Makefile, which is the only place where it is used.

Acked-by: Catalin Marinas 
Signed-off-by: Will Deacon

arm64: vdso32: Remove jump label config option in Makefile

2019-10-07T10:07:17+00:00

The jump labels are not used in vdso32 since it is not possible to run
runtime patching on them.

Remove the configuration option from the Makefile.

Cc: Will Deacon 
Cc: Catalin Marinas 
Signed-off-by: Vincenzo Frascino 
Acked-by: Catalin Marinas 
Tested-by: Catalin Marinas 
Signed-off-by: Will Deacon

arm64: vdso32: Detect binutils support for dmb ishld

2019-10-07T10:07:16+00:00

Older versions of binutils (prior to 2.24) do not support the "ISHLD"
option for memory barrier instructions, which leads to a build failure
when assembling the vdso32 library.

Add a compilation time mechanism that detects if binutils supports those
instructions and configure the kernel accordingly.

Cc: Will Deacon 
Cc: Catalin Marinas 
Reported-by: Will Deacon 
Signed-off-by: Vincenzo Frascino 
Reviewed-by: Catalin Marinas 
Tested-by: Catalin Marinas 
Signed-off-by: Will Deacon

arm64: vdso32: Fix broken compat vDSO build warnings

2019-10-07T10:07:16+00:00

The .config file and the generated include/config/auto.conf can
end up out of sync after a set of commands since
CONFIG_CROSS_COMPILE_COMPAT_VDSO is not updated correctly.

The sequence can be reproduced as follows:

$ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- defconfig
[...]
$ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- menuconfig
[set CONFIG_CROSS_COMPILE_COMPAT_VDSO="arm-linux-gnueabihf-"]
$ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu-

Which results in:

arch/arm64/Makefile:62: CROSS_COMPILE_COMPAT not defined or empty,
the compat vDSO will not be built

even though the compat vDSO has been built:

$ file arch/arm64/kernel/vdso32/vdso.so
arch/arm64/kernel/vdso32/vdso.so: ELF 32-bit LSB pie executable, ARM,
EABI5 version 1 (SYSV), dynamically linked,
BuildID[sha1]=c67f6c786f2d2d6f86c71f708595594aa25247f6, stripped

A similar case that involves changing the configuration parameter
multiple times can be reconducted to the same family of problems.

Remove the use of CONFIG_CROSS_COMPILE_COMPAT_VDSO altogether and
instead rely on the cross-compiler prefix coming from the environment
via CROSS_COMPILE_COMPAT, much like we do for the rest of the kernel.

Cc: Will Deacon 
Cc: Catalin Marinas 
Reported-by: Will Deacon 
Signed-off-by: Vincenzo Frascino 
Signed-off-by: Will Deacon

arm64: vdso: Cleanup Makefiles

2019-07-22T09:37:33+00:00

The recent changes to the vdso library for arm64 and the introduction of
the compat vdso library have generated some misalignment in the
Makefiles.

Cleanup the Makefiles for vdso and vdso32 libraries:
  * Removing unused rules.
  * Unifying the displayed compilation messages.
  * Simplifying the generic library inclusion path for
    arm64 vdso.

Cc: Catalin Marinas 
Cc: Will Deacon 
Signed-off-by: Vincenzo Frascino 
Signed-off-by: Will Deacon