linux-toradex.git/arch/mips/vdso, branch v6.7

MIPS: VDSO: Conditionally export __vdso_gettimeofday()

2023-08-23T07:06:38+00:00

ld.lld 16.0.0 and newer defaults to '--no-undefined-version', which
causes the following error when CONFIG_MIPS_CLOCK_VSYSCALL is not set:

  ld.lld: error: version script assignment of 'LINUX_2.6' to symbol '__vdso_gettimeofday' failed: symbol not defined

Only export __vdso_gettimeofday() when it will be present in the final
object file, which clears up the error.

Reported-by: kernel test robot 
Closes: https://lore.kernel.org/oe-kbuild-all/202308170532.zxFFv25c-lkp@intel.com/
Signed-off-by: Nathan Chancellor 
Reviewed-by: Fangrui Song 
Reviewed-by: Nick Desaulniers 
Reviewed-by: Philippe Mathieu-Daudé 
Signed-off-by: Thomas Bogendoerfer

vdso: Improve cmd_vdso_check to check all dynamic relocations

2023-03-21T20:15:34+00:00

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 
Signed-off-by: Thomas Gleixner 
Tested-by: Vincenzo Frascino  # for aarch64
Reviewed-by: Christophe Leroy 
Reviewed-by: Vincenzo Frascino  # for vDSO, aarch64
Acked-by: Michael Ellerman  (powerpc)
Link: https://lore.kernel.org/r/20230310190750.3323802-1-maskray@google.com

MIPS: remove CONFIG_MIPS_LD_CAN_LINK_VDSO

2023-01-27T16:14:48+00:00

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 
Reviewed-by: Nathan Chancellor 
Reviewed-by: Philippe Mathieu-Daudé 
Signed-off-by: Thomas Bogendoerfer

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

2022-11-21T16:56:53+00:00

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 
Signed-off-by: Thomas Bogendoerfer

mips: Enable KCSAN

2022-02-07T17:31:57+00:00

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

Signed-off-by: Nemanja Rakovic 
Signed-off-by: Thomas Bogendoerfer

MIPS: VDSO: remove -nostdlib compiler flag

2021-11-09T15:09:37+00:00

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 
Signed-off-by: Thomas Bogendoerfer

MIPS: Makefile: Replace -pg with CC_FLAGS_FTRACE

2021-04-21T11:44:35+00:00

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 
Signed-off-by: Thomas Bogendoerfer

Merge tag 'kbuild-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2021-02-25T18:17:31+00:00

Pull Kbuild updates from Masahiro Yamada:

 - Fix false-positive build warnings for ARCH=ia64 builds

 - Optimize dictionary size for module compression with xz

 - Check the compiler and linker versions in Kconfig

 - Fix misuse of extra-y

 - Support DWARF v5 debug info

 - Clamp SUBLEVEL to 255 because stable releases 4.4.x and 4.9.x
   exceeded the limit

 - Add generic syscall{tbl,hdr}.sh for cleanups across arches

 - Minor cleanups of genksyms

 - Minor cleanups of Kconfig

* tag 'kbuild-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (38 commits)
  initramfs: Remove redundant dependency of RD_ZSTD on BLK_DEV_INITRD
  kbuild: remove deprecated 'always' and 'hostprogs-y/m'
  kbuild: parse C= and M= before changing the working directory
  kbuild: reuse this-makefile to define abs_srctree
  kconfig: unify rule of config, menuconfig, nconfig, gconfig, xconfig
  kconfig: omit --oldaskconfig option for 'make config'
  kconfig: fix 'invalid option' for help option
  kconfig: remove dead code in conf_askvalue()
  kconfig: clean up nested if-conditionals in check_conf()
  kconfig: Remove duplicate call to sym_get_string_value()
  Makefile: Remove # characters from compiler string
  Makefile: reuse CC_VERSION_TEXT
  kbuild: check the minimum linker version in Kconfig
  kbuild: remove ld-version macro
  scripts: add generic syscallhdr.sh
  scripts: add generic syscalltbl.sh
  arch: syscalls: remove $(srctree)/ prefix from syscall tables
  arch: syscalls: add missing FORCE and fix 'targets' to make if_changed work
  gen_compile_commands: prune some directories
  kbuild: simplify access to the kernel's version
  ...

kbuild: LD_VERSION redenomination

2021-02-11T20:12:31+00:00

Commit ccbef1674a15 ("Kbuild, lto: add ld-version and ld-ifversion
macros") introduced scripts/ld-version.sh for GCC LTO.

At that time, this script handled 5 version fields because GCC LTO
needed the downstream binutils. (https://lkml.org/lkml/2014/4/8/272)

The code snippet from the submitted patch was as follows:

    # We need HJ Lu's Linux binutils because mainline binutils does not
    # support mixing assembler and LTO code in the same ld -r object.
    # XXX check if the gcc plugin ld is the expected one too
    # XXX some Fedora binutils should also support it. How to check for that?
    ifeq ($(call ld-ifversion,-ge,22710001,y),y)
        ...

However, GCC LTO was not merged into the mainline after all.
(https://lkml.org/lkml/2014/4/8/272)

So, the 4th and 5th fields were never used, and finally removed by
commit 0d61ed17dd30 ("ld-version: Drop the 4th and 5th version
components").

Since then, the last 4-digits returned by this script is always zeros.

Remove the meaningless last 4-digits. This makes the version format
consistent with GCC_VERSION, CLANG_VERSION, LLD_VERSION.

Signed-off-by: Masahiro Yamada 
Acked-by: Will Deacon 
Acked-by: Thomas Bogendoerfer

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

2021-01-18T14:40:14+00:00

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: stable@vger.kernel.org
Fixes: ee67855ecd9d ("MIPS: vdso: Allow clang's --target flag in VDSO cflags")
Link: https://github.com/ClangBuiltLinux/linux/issues/1256
Reported-by: Anders Roxell 
Signed-off-by: Nathan Chancellor 
Tested-by: Anders Roxell 
Signed-off-by: Thomas Bogendoerfer