linux.git/arch/powerpc/boot/wrapper, branch v6.6

powerpc/boot: Fix incorrect version calculation issue in ld_version

2023-01-11T05:28:43+00:00

The ld_version() function computes the wrong version value for certain
ld versions such as the following:

  $ ld --version
  GNU ld (GNU Binutils; SUSE Linux Enterprise 15)
  2.37.20211103-150100.7.37

For input 2.37.20211103, the value computed is 202348030000 which is
higher than the value for a later version like 2.39.0, which is
23900000.

This issue was highlighted because with the above ld version, the
powerpc kernel build started failing with ld error: "unrecognized option
--no-warn-rwx-segments". This was caused due to the recent commit
579aee9fc594 ("powerpc: suppress some linker warnings in recent linker
versions") which added the --no-warn-rwx-segments linker flag if the ld
version is greater than 2.39.

Due to the bug in ld_version(), ld version 2.37.20111103 is wrongly
calculated to be greater than 2.39 and the unsupported flag is added.

To fix it, if version is of the form x.y.z and length(z) == 8, then most
probably it is a date [yyyymmdd] commonly used for release snapshots and
not an actual new version. Hence, ignore the date part replacing it with
0.

Fixes: 579aee9fc594 ("powerpc: suppress some linker warnings in recent linker versions")
Signed-off-by: Ojaswin Mujoo 
[mpe: Tweak change log wording/formatting, add Fixes tag]
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20230104202437.90039-1-ojaswin@linux.ibm.com

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

2022-11-24T12:31:51+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.

  sed -i "s/egrep/grep -E/g" `grep egrep -rwl arch/powerpc`

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: Michael Ellerman 
Link: https://lore.kernel.org/r/1668764429-11540-1-git-send-email-yangtiezhu@loongson.cn

powerpc: suppress some linker warnings in recent linker versions

2022-11-24T12:31:49+00:00

This is a follow on from commit

  0d362be5b142 ("Makefile: link with -z noexecstack --no-warn-rwx-segments")

for arch/powerpc/boot to address wanrings like:

  ld: warning: opal-calls.o: missing .note.GNU-stack section implies executable stack
  ld: NOTE: This behaviour is deprecated and will be removed in a future version of the linker
  ld: warning: arch/powerpc/boot/zImage.epapr has a LOAD segment with RWX permissions

This fixes issue https://github.com/linuxppc/issues/issues/417

Signed-off-by: Stephen Rothwell 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20221010165721.106267e6@canb.auug.org.au

kbuild: build init/built-in.a just once

2022-09-28T19:40:15+00:00

Kbuild builds init/built-in.a twice; first during the ordinary
directory descending, second from scripts/link-vmlinux.sh.

We do this because UTS_VERSION contains the build version and the
timestamp. We cannot update it during the normal directory traversal
since we do not yet know if we need to update vmlinux. UTS_VERSION is
temporarily calculated, but omitted from the update check. Otherwise,
vmlinux would be rebuilt every time.

When Kbuild results in running link-vmlinux.sh, it increments the
version number in the .version file and takes the timestamp at that
time to really fix UTS_VERSION.

However, updating the same file twice is a footgun. To avoid nasty
timestamp issues, all build artifacts that depend on init/built-in.a
are atomically generated in link-vmlinux.sh, where some of them do not
need rebuilding.

To fix this issue, this commit changes as follows:

[1] Split UTS_VERSION out to include/generated/utsversion.h from
    include/generated/compile.h

    include/generated/utsversion.h is generated just before the
    vmlinux link. It is generated under include/generated/ because
    some decompressors (s390, x86) use UTS_VERSION.

[2] Split init_uts_ns and linux_banner out to init/version-timestamp.c
    from init/version.c

    init_uts_ns and linux_banner contain UTS_VERSION. During the ordinary
    directory descending, they are compiled with __weak and used to
    determine if vmlinux needs relinking. Just before the vmlinux link,
    they are compiled without __weak to embed the real version and
    timestamp.

Signed-off-by: Masahiro Yamada

powerpc: Fix all occurences of "the the"

2022-05-22T05:59:43+00:00

Rather than waiting for the bots to fix these one-by-one, fix all
occurences of "the the" throughout arch/powerpc.

Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220518142629.513007-1-mpe@ellerman.id.au

powerpc/boot: Set LC_ALL=C in wrapper script

2021-10-27T11:31:22+00:00

While trying to build a simple Image for ACADIA platform, I got the
following error:

	  WRAP    arch/powerpc/boot/simpleImage.acadia
	INFO: Uncompressed kernel (size 0x6ae7d0) overlaps the address of the wrapper(0x400000)
	INFO: Fixing the link_address of wrapper to (0x700000)
	powerpc64-linux-gnu-ld : mode d'émulation non reconnu : -T
	Émulations prises en charge : elf64ppc elf32ppc elf32ppclinux elf32ppcsim elf64lppc elf32lppc elf32lppclinux elf32lppcsim
	make[1]: *** [arch/powerpc/boot/Makefile:424 : arch/powerpc/boot/simpleImage.acadia] Erreur 1
	make: *** [arch/powerpc/Makefile:285 : simpleImage.acadia] Erreur 2

Trying again with V=1 shows the following command

	powerpc64-linux-gnu-ld -m -T arch/powerpc/boot/zImage.lds -Ttext 0x700000 --no-dynamic-linker -o arch/powerpc/boot/simpleImage.acadia -Map wrapper.map arch/powerpc/boot/fixed-head.o arch/powerpc/boot/simpleboot.o ./zImage.3278022.o arch/powerpc/boot/wrapper.a

The argument of '-m' is missing.

This is due to the wrapper script calling 'objdump -p vmlinux' and
looking for 'file format', whereas the output of objdump is:

	vmlinux:     format de fichier elf32-powerpc

	En-tête de programme:
	    LOAD off    0x00010000 vaddr 0xc0000000 paddr 0x00000000 align 2**16
	         filesz 0x0069e1d4 memsz 0x006c128c flags rwx
	    NOTE off    0x0064591c vaddr 0xc063591c paddr 0x0063591c align 2**2
	         filesz 0x00000054 memsz 0x00000054 flags ---

Add LC_ALL=C at the beginning of the wrapper script in order to get the
output expected by the script:

	vmlinux:     file format elf32-powerpc

	Program Header:
	    LOAD off    0x00010000 vaddr 0xc0000000 paddr 0x00000000 align 2**16
	         filesz 0x0069e1d4 memsz 0x006c128c flags rwx
	    NOTE off    0x0064591c vaddr 0xc063591c paddr 0x0063591c align 2**2
	         filesz 0x00000054 memsz 0x00000054 flags ---

Signed-off-by: Christophe Leroy 
Acked-by: Segher Boessenkool 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/a9ff3bc98035f63b122c051f02dc47c7aed10430.1635256089.git.christophe.leroy@csgroup.eu

powerpc: retire sbc8548 board support

2021-08-26T14:48:11+00:00

The support was for this was mainlined 13 years ago, in v2.6.25
[0e0fffe88767] just around the ppc --> powerpc migration.

I believe the board was introduced a year or two before that, so it
is roughly a 15 year old platform - with the CPU speed and memory size
that was typical for that era.

I haven't had one of these boards for several years, and availability
was discontinued several years before that.

Given that, there is no point in adding a burden to testing coverage
that builds all possible defconfigs, so it makes sense to remove it.

Of course it will remain in the git history forever, for anyone who
happens to find a functional board and wants to tinker with it.

Acked-by: Scott Wood 
Signed-off-by: Paul Gortmaker 
Signed-off-by: Michael Ellerman

powerpc/boot: Add a boot wrapper for Microwatt

2021-06-21T11:16:32+00:00

This allows microwatt's kernel to be built with an embedded device tree.

Load to arch/powerpc/boot/dtbImage.microwatt to 0x500000:

 mw_debug -b fpga stop load arch/powerpc/boot/dtbImage.microwatt 500000 start

Signed-off-by: Joel Stanley 
Signed-off-by: Paul Mackerras 
Reviewed-by: Segher Boessenkool 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/YMwX19wym3kQ7guu@thinks.paulus.ozlabs.org

kbuild: replace LANG=C with LC_ALL=C

2021-05-01T15:43:35+00:00

LANG gives a weak default to each LC_* in case it is not explicitly
defined. LC_ALL, if set, overrides all other LC_* variables.

  LANG  <  LC_CTYPE, LC_COLLATE, LC_MONETARY, LC_NUMERIC, ...  <  LC_ALL

This is why documentation such as [1] suggests to set LC_ALL in build
scripts to get the deterministic result.

LANG=C is not strong enough to override LC_* that may be set by end
users.

[1]: https://reproducible-builds.org/docs/locales/

Signed-off-by: Masahiro Yamada 
Acked-by: Michael Ellerman  (powerpc)
Reviewed-by: Matthias Maennich 
Acked-by: Matthieu Baerts  (mptcp)
Reviewed-by: Greg Kroah-Hartman

powerpc/boot/wrapper: Add "-z notext" flag to disable diagnostic

2020-11-26T11:05:43+00:00

The "-z notext" flag disables reporting an error if DT_TEXTREL is set.

  ld.lld: error: can't create dynamic relocation R_PPC64_ADDR64 against
    symbol: _start in readonly segment; recompile object files with
    -fPIC or pass '-Wl,-z,notext' to allow text relocations in the
    output
  >>> defined in
  >>> referenced by crt0.o:(.text+0x8) in archive arch/powerpc/boot/wrapper.a

The BFD linker disables this by default (though it's configurable in
current versions). LLD enables this by default. So we add the flag to
keep LLD from emitting the error.

Signed-off-by: Bill Wendling 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20201120224034.191382-2-morbo@google.com