vdso: Rename included Makefile

As the Makefile is included into other Makefiles it can not be used to
define objects to be built from the current source directory.
However the generic datastore will

vdso: Rename included Makefile

As the Makefile is included into other Makefiles it can not be used to
define objects to be built from the current source directory.
However the generic datastore will introduce such a local source file.
Rename the included Makefile so it is clear how it is to be used and to
make room for a regular Makefile in lib/vdso/.

Signed-off-by: Thomas Weißschuh <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Link: https://lore.kernel.org/all/[email protected]

show more ...

Makefile: remove redundant tool coverage variables

Now Kbuild provides reasonable defaults for objtool, sanitizers, and
profilers.

Remove redundant variables.

Note:

This commit changes the covera

Makefile: remove redundant tool coverage variables

Now Kbuild provides reasonable defaults for objtool, sanitizers, and
profilers.

Remove redundant variables.

Note:

This commit changes the coverage for some objects:

- include arch/mips/vdso/vdso-image.o into UBSAN, GCOV, KCOV
- include arch/sparc/vdso/vdso-image-*.o into UBSAN
- include arch/sparc/vdso/vma.o into UBSAN
- include arch/x86/entry/vdso/extable.o into KASAN, KCSAN, UBSAN, GCOV, KCOV
- include arch/x86/entry/vdso/vdso-image-*.o into KASAN, KCSAN, UBSAN, GCOV, KCOV
- include arch/x86/entry/vdso/vdso32-setup.o into KASAN, KCSAN, UBSAN, GCOV, KCOV
- include arch/x86/entry/vdso/vma.o into GCOV, KCOV
- include arch/x86/um/vdso/vma.o into KASAN, GCOV, KCOV

I believe these are positive effects because all of them are kernel
space objects.

Signed-off-by: Masahiro Yamada <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Tested-by: Roberto Sassu <[email protected]>

show more ...

kbuild: use $(src) instead of $(srctree)/$(src) for source directory

Kbuild conventionally uses $(obj)/ for generated files, and $(src)/ for
checked-in source files. It is merely a convention withou

kbuild: use $(src) instead of $(srctree)/$(src) for source directory

Kbuild conventionally uses $(obj)/ for generated files, and $(src)/ for
checked-in source files. It is merely a convention without any functional
difference. In fact, $(obj) and $(src) are exactly the same, as defined
in scripts/Makefile.build:

src := $(obj)

When the kernel is built in a separate output directory, $(src) does
not accurately reflect the source directory location. While Kbuild
resolves this discrepancy by specifying VPATH=$(srctree) to search for
source files, it does not cover all cases. For example, when adding a
header search path for local headers, -I$(srctree)/$(src) is typically
passed to the compiler.

This introduces inconsistency between upstream and downstream Makefiles
because $(src) is used instead of $(srctree)/$(src) for the latter.

To address this inconsistency, this commit changes the semantics of
$(src) so that it always points to the directory in the source tree.

Going forward, the variables used in Makefiles will have the following
meanings:

$(obj) - directory in the object tree
$(src) - directory in the source tree (changed by this commit)
$(objtree) - the top of the kernel object tree
$(srctree) - the top of the kernel source tree

Consequently, $(srctree)/$(src) in upstream Makefiles need to be replaced
with $(src).

Signed-off-by: Masahiro Yamada <[email protected]>
Reviewed-by: Nicolas Schier <[email protected]>

show more ...

vdso: Improve cmd_vdso_check to check all dynamic relocations

The actual intention is that no dynamic relocation exists in the VDSO. For
this the VDSO build validates that the resulting .so file doe

vdso: Improve cmd_vdso_check to check all dynamic relocations

The actual intention is that no dynamic relocation exists in the VDSO. For
this the VDSO build validates that the resulting .so file does not have any
relocations which are specified via $(ARCH_REL_TYPE_ABS) per architecture,
which is fragile as e.g. ARM64 lacks an entry for R_AARCH64_RELATIVE. Aside
of that ARCH_REL_TYPE_ABS is a misnomer as it checks for relative
relocations too.

However, some GNU ld ports produce unneeded R_*_NONE relocation entries. If
a port fails to determine the exact .rel[a].dyn size, the trailing zeros
become R_*_NONE relocations. E.g. ld's powerpc port recently fixed
https://sourceware.org/bugzilla/show_bug.cgi?id=29540). R_*_NONE are
generally a no-op in the dynamic loaders. So just ignore them.

Remove the ARCH_REL_TYPE_ABS defines and just validate that the resulting
.so file does not contain any R_* relocation entries except R_*_NONE.

Signed-off-by: Fangrui Song <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Tested-by: Vincenzo Frascino <[email protected]> # for aarch64
Reviewed-by: Christophe Leroy <[email protected]>
Reviewed-by: Vincenzo Frascino <[email protected]> # for vDSO, aarch64
Acked-by: Michael Ellerman <[email protected]> (powerpc)
Link: https://lore.kernel.org/r/[email protected]

show more ...

MIPS: remove CONFIG_MIPS_LD_CAN_LINK_VDSO

Given commit e4412739472b ("Documentation: raise minimum supported
version of binutils to 2.25"), CONFIG_MIPS_LD_CAN_LINK_VDSO is always
'y'.

Signed-off-by

MIPS: remove CONFIG_MIPS_LD_CAN_LINK_VDSO

Given commit e4412739472b ("Documentation: raise minimum supported
version of binutils to 2.25"), CONFIG_MIPS_LD_CAN_LINK_VDSO is always
'y'.

Signed-off-by: Masahiro Yamada <[email protected]>
Reviewed-by: Nathan Chancellor <[email protected]>
Reviewed-by: Philippe Mathieu-Daudé <[email protected]>
Signed-off-by: Thomas Bogendoerfer <[email protected]>

show more ...

MIPS: Use "grep -E" instead of "egrep"

The latest version of grep claims the egrep is now obsolete so the build
now contains warnings that look like:
egrep: warning: egrep is obsolescent; using gre

MIPS: Use "grep -E" instead of "egrep"

The latest version of grep claims the egrep is now obsolete so the build
now contains warnings that look like:
egrep: warning: egrep is obsolescent; using grep -E
fix this up by moving the related file to use "grep -E" instead.

Here are the steps to install the latest grep:

wget http://ftp.gnu.org/gnu/grep/grep-3.8.tar.gz
tar xf grep-3.8.tar.gz
cd grep-3.8 && ./configure && make
sudo make install
export PATH=/usr/local/bin:$PATH

Signed-off-by: Tiezhu Yang <[email protected]>
Signed-off-by: Thomas Bogendoerfer <[email protected]>

show more ...

mips: Enable KCSAN

This patch enables KCSAN for the 64-bit version. Updated rules
for the incompatible compilation units (vdso, boot/compressed).

Signed-off-by: Nemanja Rakovic <nemanja.rakovic@syr

mips: Enable KCSAN

This patch enables KCSAN for the 64-bit version. Updated rules
for the incompatible compilation units (vdso, boot/compressed).

Signed-off-by: Nemanja Rakovic <[email protected]>
Signed-off-by: Thomas Bogendoerfer <[email protected]>

show more ...

MIPS: VDSO: remove -nostdlib compiler flag

The -nostdlib option requests the compiler to not use the standard
system startup files or libraries when linking. It is effective only
when $(CC) is used

MIPS: VDSO: remove -nostdlib compiler flag

The -nostdlib option requests the compiler to not use the standard
system startup files or libraries when linking. It is effective only
when $(CC) is used as a linker driver.

Since commit 2ff906994b6c ("MIPS: VDSO: Use $(LD) instead of $(CC) to
link VDSO"), $(LD) is directly used, hence -nostdlib is unneeded.

Signed-off-by: Masahiro Yamada <[email protected]>
Signed-off-by: Thomas Bogendoerfer <[email protected]>

show more ...

MIPS: Makefile: Replace -pg with CC_FLAGS_FTRACE

This patch replaces the "open-coded" -pg compile flag with a CC_FLAGS_FTRACE
makefile variable which architectures can override if a different option

MIPS: Makefile: Replace -pg with CC_FLAGS_FTRACE

This patch replaces the "open-coded" -pg compile flag with a CC_FLAGS_FTRACE
makefile variable which architectures can override if a different option
should be used for code generation.

Signed-off-by: zhaoxiao <[email protected]>
Signed-off-by: Thomas Bogendoerfer <[email protected]>

show more ...

MIPS: VDSO: Use CLANG_FLAGS instead of filtering out '--target='

Commit ee67855ecd9d ("MIPS: vdso: Allow clang's --target flag in VDSO
cflags") allowed the '--target=' flag from the main Makefile to

MIPS: VDSO: Use CLANG_FLAGS instead of filtering out '--target='

Commit ee67855ecd9d ("MIPS: vdso: Allow clang's --target flag in VDSO
cflags") allowed the '--target=' flag from the main Makefile to filter
through to the vDSO. However, it did not bring any of the other clang
specific flags for controlling the integrated assembler and the GNU
tools locations (--prefix=, --gcc-toolchain=, and -no-integrated-as).
Without these, we will get a warning (visible with tinyconfig):

arch/mips/vdso/elf.S:14:1: warning: DWARF2 only supports one section per
compilation unit
.pushsection .note.Linux, "a",@note ; .balign 4 ; .long 2f - 1f ; .long
4484f - 3f ; .long 0 ; 1:.asciz "Linux" ; 2:.balign 4 ; 3:
^
arch/mips/vdso/elf.S:34:2: warning: DWARF2 only supports one section per
compilation unit
.section .mips_abiflags, "a"
^

All of these flags are bundled up under CLANG_FLAGS in the main Makefile
and exported so that they can be added to Makefiles that set their own
CFLAGS. Use this value instead of filtering out '--target=' so there is
no warning and all of the tools are properly used.

Cc: [email protected]
Fixes: ee67855ecd9d ("MIPS: vdso: Allow clang's --target flag in VDSO cflags")
Link: https://github.com/ClangBuiltLinux/linux/issues/1256
Reported-by: Anders Roxell <[email protected]>
Signed-off-by: Nathan Chancellor <[email protected]>
Tested-by: Anders Roxell <[email protected]>
Signed-off-by: Thomas Bogendoerfer <[email protected]>

show more ...

kbuild: explicitly specify the build id style

ld's --build-id defaults to "sha1" style, while lld defaults to "fast".
The build IDs are very different between the two, which may confuse
programs tha

kbuild: explicitly specify the build id style

ld's --build-id defaults to "sha1" style, while lld defaults to "fast".
The build IDs are very different between the two, which may confuse
programs that reference them.

Signed-off-by: Bill Wendling <[email protected]>
Acked-by: David S. Miller <[email protected]>
Signed-off-by: Masahiro Yamada <[email protected]>

show more ...

kbuild: remove cc-option test of -fno-stack-protector

Some Makefiles already pass -fno-stack-protector unconditionally.
For example, arch/arm64/kernel/vdso/Makefile, arch/x86/xen/Makefile.

No probl

kbuild: remove cc-option test of -fno-stack-protector

Some Makefiles already pass -fno-stack-protector unconditionally.
For example, arch/arm64/kernel/vdso/Makefile, arch/x86/xen/Makefile.

No problem report so far about hard-coding this option. So, we can
assume all supported compilers know -fno-stack-protector.

GCC 4.8 and Clang support this option (https://godbolt.org/z/_HDGzN)

Get rid of cc-option from -fno-stack-protector.

Remove CONFIG_CC_HAS_STACKPROTECTOR_NONE, which is always 'y'.

Note:
arch/mips/vdso/Makefile adds -fno-stack-protector twice, first
unconditionally, and second conditionally. I removed the second one.

Signed-off-by: Masahiro Yamada <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Acked-by: Ard Biesheuvel <[email protected]>
Reviewed-by: Nick Desaulniers <[email protected]>

show more ...

MIPS: VDSO: Use $(LD) instead of $(CC) to link VDSO

Currently, the VDSO is being linked through $(CC). This does not match
how the rest of the kernel links objects, which is through the $(LD)
variab

MIPS: VDSO: Use $(LD) instead of $(CC) to link VDSO

Currently, the VDSO is being linked through $(CC). This does not match
how the rest of the kernel links objects, which is through the $(LD)
variable.

When clang is built in a default configuration, it first attempts to use
the target triple's default linker then the system's default linker,
unless told otherwise through -fuse-ld=... We do not use -fuse-ld=
because it can be brittle and we have support for invoking $(LD)
directly. See commit fe00e50b2db8c ("ARM: 8858/1: vdso: use $(LD)
instead of $(CC) to link VDSO") and commit 691efbedc60d2 ("arm64: vdso:
use $(LD) instead of $(CC) to link VDSO") for examples of doing this in
the VDSO.

Do the same thing here. Replace the custom linking logic with $(cmd_ld)
and ldflags-y so that $(LD) is respected. We need to explicitly add two
flags to the linker that were implicitly passed by the compiler:
-G 0 (which comes from ccflags-vdso) and --eh-frame-hdr.

Before this patch (generated by adding '-v' to VDSO_LDFLAGS):

<gcc_prefix>/libexec/gcc/mips64-linux/9.3.0/collect2 \
-plugin <gcc_prefix>/libexec/gcc/mips64-linux/9.3.0/liblto_plugin.so \
-plugin-opt=<gcc_prefix>/libexec/gcc/mips64-linux/9.3.0/lto-wrapper \
-plugin-opt=-fresolution=/tmp/ccGEi5Ka.res \
--eh-frame-hdr \
-G 0 \
-EB \
-mips64r2 \
-shared \
-melf64btsmip \
-o arch/mips/vdso/vdso.so.dbg.raw \
-L<gcc_prefix>/lib/gcc/mips64-linux/9.3.0/64 \
-L<gcc_prefix>/lib/gcc/mips64-linux/9.3.0 \
-L<gcc_prefix>/lib/gcc/mips64-linux/9.3.0/../../../../mips64-linux/lib \
-Bsymbolic \
--no-undefined \
-soname=linux-vdso.so.1 \
-EB \
--hash-style=sysv \
--build-id \
-T arch/mips/vdso/vdso.lds \
arch/mips/vdso/elf.o \
arch/mips/vdso/vgettimeofday.o \
arch/mips/vdso/sigreturn.o

After this patch:

<gcc_prefix>/bin/mips64-linux-ld \
-m elf64btsmip \
-Bsymbolic \
--no-undefined \
-soname=linux-vdso.so.1 \
-EB \
-nostdlib \
-shared \
-G 0 \
--eh-frame-hdr \
--hash-style=sysv \
--build-id \
-T arch/mips/vdso/vdso.lds \
arch/mips/vdso/elf.o \
arch/mips/vdso/vgettimeofday.o
arch/mips/vdso/sigreturn.o \
-o arch/mips/vdso/vdso.so.dbg.raw

Note that we leave behind -mips64r2. Turns out that ld ignores it (see
get_emulation in ld/ldmain.c). This is true of current trunk and 2.23,
which is the minimum supported version for the kernel:

https://sourceware.org/git/?p=binutils-gdb.git;a=blob;f=ld/ldmain.c;hb=aa4209e7b679afd74a3860ce25659e71cc4847d5#l593
https://sourceware.org/git/?p=binutils-gdb.git;a=blob;f=ld/ldmain.c;hb=a55e30b51bc6227d8d41f707654d0a5620978dcf#l641

Before this patch, LD=ld.lld did nothing:

$ llvm-readelf -p.comment arch/mips/vdso/vdso.so.dbg | sed 's/(.*//'
String dump of section '.comment':
[ 0] ClangBuiltLinux clang version 11.0.0

After this patch, it does:

$ llvm-readelf -p.comment arch/mips/vdso/vdso.so.dbg | sed 's/(.*//'
String dump of section '.comment':
[ 0] Linker: LLD 11.0.0
[ 62] ClangBuiltLinux clang version 11.0.0

Link: https://github.com/ClangBuiltLinux/linux/issues/785
Signed-off-by: Nathan Chancellor <[email protected]>
Signed-off-by: Thomas Bogendoerfer <[email protected]>

show more ...

MIPS: VDSO: Move disabling the VDSO logic to Kconfig

After commit 9553d16fa671 ("init/kconfig: Add LD_VERSION Kconfig"), we
have access to GNU ld's version at configuration time. As a result, we
can

MIPS: VDSO: Move disabling the VDSO logic to Kconfig

After commit 9553d16fa671 ("init/kconfig: Add LD_VERSION Kconfig"), we
have access to GNU ld's version at configuration time. As a result, we
can make it clearer under what configuration circumstances the MIPS VDSO
needs to be disabled.

This is a prerequisite for getting rid of the MIPS VDSO binutils
warning and linking the VDSO when LD is ld.lld. Wrapping the call to
ld-ifversion with CONFIG_LD_IS_LLD does not work because the config
values are wiped away during 'make clean'.

Signed-off-by: Nathan Chancellor <[email protected]>
Signed-off-by: Thomas Bogendoerfer <[email protected]>

show more ...

MIPS: vdso: Wrap -mexplicit-relocs in cc-option

Clang does not support this option and errors out:

clang-11: error: unknown argument: '-mexplicit-relocs'

Clang does not appear to need this flag li

MIPS: vdso: Wrap -mexplicit-relocs in cc-option

Clang does not support this option and errors out:

clang-11: error: unknown argument: '-mexplicit-relocs'

Clang does not appear to need this flag like GCC does because the jalr
check that was added in commit 976c23af3ee5 ("mips: vdso: add build
time check that no 'jalr t9' calls left") passes just fine with

$ make ARCH=mips CC=clang CROSS_COMPILE=mipsel-linux-gnu- malta_defconfig arch/mips/vdso/

even before commit d3f703c4359f ("mips: vdso: fix 'jalr t9' crash in
vdso code").

-mrelax-pic-calls has been supported since clang 9, which is the
earliest version that could build a working MIPS kernel, and it is the
default for clang so just leave it be.

Fixes: d3f703c4359f ("mips: vdso: fix 'jalr t9' crash in vdso code")
Link: https://github.com/ClangBuiltLinux/linux/issues/890
Signed-off-by: Nathan Chancellor <[email protected]>
Reviewed-by: Nick Desaulniers <[email protected]>
Tested-by: Nick Desaulniers <[email protected]>
Signed-off-by: Paul Burton <[email protected]>
Cc: Ralf Baechle <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]

show more ...

mips: vdso: add build time check that no 'jalr t9' calls left

vdso shared object cannot have GOT based PIC 'jalr t9' calls
because nobody set GOT table in vdso. Contributing into vdso
.o files are c

mips: vdso: add build time check that no 'jalr t9' calls left

vdso shared object cannot have GOT based PIC 'jalr t9' calls
because nobody set GOT table in vdso. Contributing into vdso
.o files are compiled in PIC mode and as result for internal
static functions calls compiler will generate 'jalr t9'
instructions. Those are supposed to be converted into PC
relative 'bal' calls by linker when relocation are processed.

Mips global GOT entries do have dynamic relocations and they
will be caught by cmd_vdso_check Makefile rule. Static PIC
calls go through mips local GOT entries that do not have
dynamic relocations. For those 'jalr t9' calls could be present
but without dynamic relocations and they need to be converted
to 'bal' calls by linker.

Add additional build time check to make sure that no 'jalr t9'
slip through because of some toolchain misconfiguration that
prevents 'jalr t9' to 'bal' conversion.

Signed-off-by: Victor Kamensky <[email protected]>
Signed-off-by: Paul Burton <[email protected]>
Cc: [email protected]
Cc: Ralf Baechle <[email protected]>
Cc: James Hogan <[email protected]>
Cc: Vincenzo Frascino <[email protected]>
Cc: [email protected]
Cc: [email protected]

show more ...

MIPS: Disable VDSO time functionality on microMIPS

A check we're about to add to pick up on function calls that depend on
bogus use of the GOT in the VDSO picked up on instances of such function
cal

MIPS: Disable VDSO time functionality on microMIPS

A check we're about to add to pick up on function calls that depend on
bogus use of the GOT in the VDSO picked up on instances of such function
calls in microMIPS builds. Since the code appears genuinely problematic,
and given the relatively small amount of use & testing that microMIPS
sees, go ahead & disable the VDSO for microMIPS builds.

Signed-off-by: Paul Burton <[email protected]>

show more ...

mips: vdso: fix 'jalr t9' crash in vdso code

Observed that when kernel is built with Yocto mips64-poky-linux-gcc,
and mips64-poky-linux-gnun32-gcc toolchain, resulting vdso contains
'jalr t9' instru

mips: vdso: fix 'jalr t9' crash in vdso code

Observed that when kernel is built with Yocto mips64-poky-linux-gcc,
and mips64-poky-linux-gnun32-gcc toolchain, resulting vdso contains
'jalr t9' instructions in its code and since in vdso case nobody
sets GOT table code crashes when instruction reached. On other hand
observed that when kernel is built mips-poky-linux-gcc toolchain, the
same 'jalr t9' instruction are replaced with PC relative function
calls using 'bal' instructions.

The difference boils down to -mrelax-pic-calls and -mexplicit-relocs
gcc options that gets different default values depending on gcc
target triplets and corresponding binutils. -mrelax-pic-calls got
enabled by default only in mips-poky-linux-gcc case. MIPS binutils
ld relies on R_MIPS_JALR relocation to convert 'jalr t9' into 'bal'
and such relocation is generated only if -mrelax-pic-calls option
is on.

Please note 'jalr t9' conversion to 'bal' can happen only to static
functions. These static PIC calls use mips local GOT entries that
are supposed to be filled with start of DSO value by run-time linker
(missing in VDSO case) and they do not have dynamic relocations.
Global mips GOT entries must have dynamic relocations and they should
be prevented by cmd_vdso_check Makefile rule.

Solution call out -mrelax-pic-calls and -mexplicit-relocs options
explicitly while compiling MIPS vdso code. That would get correct
and consistent between different toolchains behaviour.

Reported-by: Bruce Ashfield <[email protected]>
Signed-off-by: Victor Kamensky <[email protected]>
Signed-off-by: Paul Burton <[email protected]>
Cc: [email protected]
Cc: Ralf Baechle <[email protected]>
Cc: James Hogan <[email protected]>
Cc: Vincenzo Frascino <[email protected]>
Cc: [email protected]

show more ...

kbuild: rename hostprogs-y/always to hostprogs/always-y

In old days, the "host-progs" syntax was used for specifying host
programs. It was renamed to the current "hostprogs-y" in 2004.

It is typica

kbuild: rename hostprogs-y/always to hostprogs/always-y

In old days, the "host-progs" syntax was used for specifying host
programs. It was renamed to the current "hostprogs-y" in 2004.

It is typically useful in scripts/Makefile because it allows Kbuild to
selectively compile host programs based on the kernel configuration.

This commit renames like follows:

always -> always-y
hostprogs-y -> hostprogs

So, scripts/Makefile will look like this:

always-$(CONFIG_BUILD_BIN2C) += ...
always-$(CONFIG_KALLSYMS) += ...
...
hostprogs := $(always-y) $(always-m)

I think this makes more sense because a host program is always a host
program, irrespective of the kernel configuration. We want to specify
which ones to compile by CONFIG options, so always-y will be handier.

The "always", "hostprogs-y", "hostprogs-m" will be kept for backward
compatibility for a while.

Signed-off-by: Masahiro Yamada <[email protected]>

show more ...

MIPS: vdso: Define BUILD_VDSO32 when building a 32bit kernel

The confinement of the 32bit specific VDSO functions missed to define
BUILD_VDSO32 when building a 32bit MIPS kernel:

arch/mips/vdso/vge

MIPS: vdso: Define BUILD_VDSO32 when building a 32bit kernel

The confinement of the 32bit specific VDSO functions missed to define
BUILD_VDSO32 when building a 32bit MIPS kernel:

arch/mips/vdso/vgettimeofday.c: In function __vdso_clock_gettime:
arch/mips/vdso/vgettimeofday.c:17:9: error: implicit declaration of function __cvdso_clock_gettime32

arch/mips/vdso/vgettimeofday.c: In function __vdso_clock_getres:
arch/mips/vdso/vgettimeofday.c:39:9: error: implicit declaration of function __cvdso_clock_getres_time32

Force the define for 32bit builds in the VDSO Makefile.

Fixes: bf279849ad59 ("lib/vdso: Build 32 bit specific functions in the right context")
Reported-by: kbuild test robot <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Acked-by: Paul Burton <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

show more ...

MIPS: allow building with kcov coverage

Add ARCH_HAS_KCOV and HAVE_GCC_PLUGINS to MIPS config.
Disable instrumentation of vdso to avoid build failure.

Signed-off-by: Alexey Khoroshilov <khoroshilov

MIPS: allow building with kcov coverage

Add ARCH_HAS_KCOV and HAVE_GCC_PLUGINS to MIPS config.
Disable instrumentation of vdso to avoid build failure.

Signed-off-by: Alexey Khoroshilov <[email protected]>
Signed-off-by: Paul Burton <[email protected]>
Cc: Ralf Baechle <[email protected]>
Cc: James Hogan <[email protected]>
Cc: [email protected]
Cc: [email protected]

show more ...

MIPS: Disable Loongson MMI instructions for kernel build

GCC 9.x automatically enables support for Loongson MMI instructions when
using some -march= flags, and then errors out when -msoft-float is
s

MIPS: Disable Loongson MMI instructions for kernel build

GCC 9.x automatically enables support for Loongson MMI instructions when
using some -march= flags, and then errors out when -msoft-float is
specified with:

cc1: error: ‘-mloongson-mmi’ must be used with ‘-mhard-float’

The kernel shouldn't be using these MMI instructions anyway, just as it
doesn't use floating point instructions. Explicitly disable them in
order to fix the build with GCC 9.x.

Signed-off-by: Paul Burton <[email protected]>
Fixes: 3702bba5eb4f ("MIPS: Loongson: Add GCC 4.4 support for Loongson2E")
Fixes: 6f7a251a259e ("MIPS: Loongson: Add basic Loongson 2F support")
Fixes: 5188129b8c9f ("MIPS: Loongson-3: Improve -march option and move it to Platform")
Cc: Huacai Chen <[email protected]>
Cc: Jiaxun Yang <[email protected]>
Cc: [email protected] # v2.6.32+
Cc: [email protected]

show more ...

MIPS: VDSO: Fix build for binutils < 2.25

Versions of binutils prior to 2.25 are unable to link our VDSO due to an
unsupported R_MIPS_PC32 relocation generated by the ".word _start - ."
line of the

MIPS: VDSO: Fix build for binutils < 2.25

Versions of binutils prior to 2.25 are unable to link our VDSO due to an
unsupported R_MIPS_PC32 relocation generated by the ".word _start - ."
line of the inline asm in get_vdso_base(). As such, the intent is that
when building with binutils older than 2.25 we don't build code for
gettimeofday() & friends in the VDSO that rely upon get_vdso_base().

Commit 24640f233b46 ("mips: Add support for generic vDSO") converted us
to using generic VDSO infrastructure, and as part of that the
gettimeofday() functionality moved to a new vgettimeofday.c file. The
check for binutils < 2.25 wasn't updated to handle this new filename,
and so it continues trying to remove the old unused filename from the
build. The end result is that we try to include the gettimeofday() code
in builds that will fail to link.

Fix this by updating the binutils < 2.25 case to remove vgettimeofday.c
from obj-vdso-y, rather than gettimeofday.c.

Signed-off-by: Paul Burton <[email protected]>
Fixes: 24640f233b46 ("mips: Add support for generic vDSO")
Cc: Vincenzo Frascino <[email protected]>
Cc: [email protected]

show more ...

mips: vdso: Fix flip/flop vdso building bug

Running "make" on an already compiled kernel tree will rebuild the
vdso library even if this has not been modified.

$ make
GEN Makefile
Using lin

mips: vdso: Fix flip/flop vdso building bug

Running "make" on an already compiled kernel tree will rebuild the
vdso library even if this has not been modified.

$ make
GEN Makefile
Using linux as source for kernel
CALL linux/scripts/atomic/check-atomics.sh
CALL linux/scripts/checksyscalls.sh
<stdin>:1511:2: warning: #warning syscall clone3 not implemented [-Wcpp]
CHK include/generated/compile.h
VDSO arch/mips/vdso/vdso.so.dbg.raw
OBJCOPY arch/mips/vdso/vdso.so.raw
GENVDSO arch/mips/vdso/vdso-image.c
CC arch/mips/vdso/vdso-image.o
AR arch/mips/vdso/built-in.a
AR arch/mips/built-in.a
CHK include/generated/autoksyms.h
GEN .version
CHK include/generated/compile.h
UPD include/generated/compile.h
CC init/version.o
AR init/built-in.a
LD vmlinux.o
MODPOST vmlinux.o
MODINFO modules.builtin.modinfo
KSYM .tmp_kallsyms1.o
KSYM .tmp_kallsyms2.o
LD vmlinux
SORTEX vmlinux
SYSMAP System.map
Building modules, stage 2.
ITS arch/mips/boot/vmlinux.gz.its
OBJCOPY arch/mips/boot/vmlinux.bin
MODPOST 7 modules
GZIP arch/mips/boot/vmlinux.bin.gz
ITB arch/mips/boot/vmlinux.gz.itb

The issue is generated by the fact that "if_changed" is called twice
in a single target.

Fix the build bug merging the two commands into a single function.

Signed-off-by: Vincenzo Frascino <[email protected]>
Signed-off-by: Paul Burton <[email protected]>

show more ...

mips: vdso: Fix source path

The vdso library for o32 and n32 does not compile compile correctly when
building outside of the source tree due to a wrong inclusion path for
config-n32-o32-env.c result

mips: vdso: Fix source path

The vdso library for o32 and n32 does not compile compile correctly when
building outside of the source tree due to a wrong inclusion path for
config-n32-o32-env.c resulting in the error below:

cc1: fatal error: arch/mips/vdso/config-n32-o32-env.c:
No such file or dnirectory
compilation terminated.
arch/mips/vdso/Makefile:153: recipe for target
'arch/mips/vdso/vgettimeofday-o32.o' failed
make[3]: *** [arch/mips/vdso/vgettimeofday-o32.o] Error 1
scripts/Makefile.build:490: recipe for target 'arch/mips/vdso' failed

Fix the config-n32-o32-env.c inclusion path prepending the $(srctree)
variable.

Signed-off-by: Vincenzo Frascino <[email protected]>
[[email protected]: Note that this occurs specifically when building
outside of the source tree.]
Signed-off-by: Paul Burton <[email protected]>

show more ...