Commit Graph

47 Commits

Author SHA1 Message Date
Linus Torvalds 2646719a48 Kbuild updates for v5.2
- allow users to invoke 'make' out of the source tree
 
 - refactor scripts/mkmakefile
 
 - deprecate KBUILD_SRC, which was used to track the source tree
   location for O= build.
 
 - fix recordmcount.pl in case objdump output is localized
 
 - turn unresolved symbols in external modules to errors from warnings
   by default; pass KBUILD_MODPOST_WARN=1 to get them back to warnings
 
 - generate modules.builtin.modinfo to collect .modinfo data from
   built-in modules
 
 - misc Makefile cleanups
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Merge tag 'kbuild-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - allow users to invoke 'make' out of the source tree

 - refactor scripts/mkmakefile

 - deprecate KBUILD_SRC, which was used to track the source tree
   location for O= build.

 - fix recordmcount.pl in case objdump output is localized

 - turn unresolved symbols in external modules to errors from warnings
   by default; pass KBUILD_MODPOST_WARN=1 to get them back to warnings

 - generate modules.builtin.modinfo to collect .modinfo data from
   built-in modules

 - misc Makefile cleanups

* tag 'kbuild-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (21 commits)
  .gitignore: add more all*.config patterns
  moduleparam: Save information about built-in modules in separate file
  Remove MODULE_ALIAS() calls that take undefined macro
  .gitignore: add leading and trailing slashes to generated directories
  scripts/tags.sh: fix direct execution of scripts/tags.sh
  scripts: override locale from environment when running recordmcount.pl
  samples: kobject: allow CONFIG_SAMPLE_KOBJECT to become y
  samples: seccomp: turn CONFIG_SAMPLE_SECCOMP into a bool option
  kbuild: move Documentation to vmlinux-alldirs
  kbuild: move samples/ to KBUILD_VMLINUX_OBJS
  modpost: make KBUILD_MODPOST_WARN also configurable for external modules
  kbuild: check arch/$(SRCARCH)/include/generated before out-of-tree build
  kbuild: remove unneeded dependency for include/config/kernel.release
  memory: squash drivers/memory/Makefile.asm-offsets
  kbuild: use $(srctree) instead of KBUILD_SRC to check out-of-tree build
  kbuild: mkmakefile: generate a simple wrapper of top Makefile
  kbuild: mkmakefile: do not check the generated Makefile marker
  kbuild: allow Kbuild to start from any directory
  kbuild: pass $(MAKECMDGOALS) to sub-make as is
  kbuild: fix warning "overriding recipe for target 'Makefile'"
  ...
2019-05-08 12:25:12 -07:00
Alexey Gladkov 898490c010 moduleparam: Save information about built-in modules in separate file
Problem:

When a kernel module is compiled as a separate module, some important
information about the kernel module is available via .modinfo section of
the module.  In contrast, when the kernel module is compiled into the
kernel, that information is not available.

Information about built-in modules is necessary in the following cases:

1. When it is necessary to find out what additional parameters can be
passed to the kernel at boot time.

2. When you need to know which module names and their aliases are in
the kernel. This is very useful for creating an initrd image.

Proposal:

The proposed patch does not remove .modinfo section with module
information from the vmlinux at the build time and saves it into a
separate file after kernel linking. So, the kernel does not increase in
size and no additional information remains in it. Information is stored
in the same format as in the separate modules (null-terminated string
array). Because the .modinfo section is already exported with a separate
modules, we are not creating a new API.

It can be easily read in the userspace:

$ tr '\0' '\n' < modules.builtin.modinfo
ext4.softdep=pre: crc32c
ext4.license=GPL
ext4.description=Fourth Extended Filesystem
ext4.author=Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others
ext4.alias=fs-ext4
ext4.alias=ext3
ext4.alias=fs-ext3
ext4.alias=ext2
ext4.alias=fs-ext2
md_mod.alias=block-major-9-*
md_mod.alias=md
md_mod.description=MD RAID framework
md_mod.license=GPL
md_mod.parmtype=create_on_open:bool
md_mod.parmtype=start_dirty_degraded:int
...

Co-Developed-by: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org>
Signed-off-by: Gleb Fotengauer-Malinovskiy <glebfm@altlinux.org>
Signed-off-by: Alexey Gladkov <gladkov.alexey@gmail.com>
Acked-by: Jessica Yu <jeyu@kernel.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-07 21:50:24 +09:00
Andrii Nakryiko 581b31c36c kbuild: tolerate missing pahole when generating BTF
When BTF generation is enabled through CONFIG_DEBUG_INFO_BTF,
scripts/link-vmlinux.sh detects if pahole version is too old and
gracefully continues build process, skipping BTF generation build step.
But if pahole is not available, build will still fail. This patch adds
check for whether pahole exists at all and bails out gracefully, if not.

Cc: Alexei Starovoitov <ast@fb.com>
Reported-by: Yonghong Song <yhs@fb.com>
Fixes: e83b9f5544 ("kbuild: add ability to generate BTF type info for vmlinux")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-05-06 10:18:47 +02:00
Andrii Nakryiko 68e5ab1fc8 kbuild: handle old pahole more gracefully when generating BTF
When CONFIG_DEBUG_INFO_BTF is enabled but available version of pahole is too
old to support BTF generation, build script is supposed to emit warning and
proceed with the build. Due to using exit instead of return from BASH function,
existing handling code prematurely exits exit code 0, not completing some of
the build steps. This patch fixes issue by correctly returning just from
gen_btf() function only.

Fixes: e83b9f5544 ("kbuild: add ability to generate BTF type info for vmlinux")
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-04-16 09:47:50 +02:00
Andrii Nakryiko e83b9f5544 kbuild: add ability to generate BTF type info for vmlinux
This patch adds new config option to trigger generation of BTF type
information from DWARF debuginfo for vmlinux and kernel modules through
pahole, which in turn relies on libbpf for btf_dedup() algorithm.

The intent is to record compact type information of all types used
inside kernel, including all the structs/unions/typedefs/etc. This
enables BPF's compile-once-run-everywhere ([0]) approach, in which
tracing programs that are inspecting kernel's internal data (e.g.,
struct task_struct) can be compiled on a system running some kernel
version, but would be possible to run on other kernel versions (and
configurations) without recompilation, even if the layout of structs
changed and/or some of the fields were added, removed, or renamed.

This is only possible if BPF loader can get kernel type info to adjust
all the offsets correctly. This patch is a first time in this direction,
making sure that BTF type info is part of Linux kernel image in
non-loadable ELF section.

BTF deduplication ([1]) algorithm typically provides 100x savings
compared to DWARF data, so resulting .BTF section is not big as is
typically about 2MB in size.

[0] http://vger.kernel.org/lpc-bpf2018.html#session-2
[1] https://facebookmicrosites.github.io/bpf/blog/2018/11/14/btf-enhancement.html

Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-04-03 00:53:07 +02:00
Masahiro Yamada 94cf8acc38 kbuild: source include/config/auto.conf instead of ${KCONFIG_CONFIG}
As commit 423a8155fa ("kbuild: Fix reading of .config in
link-vmlinux.sh") addressed, some shells fail to perform '.' if
${KCONFIG_CONFIG} does not contain a slash at all.

Instead, we can source include/config/auto.conf, which obviously
contain slashes, and we do not expect its file path overridden by
a user. Perhaps, the performance might be slightly better since
unset CONFIG options are stripped from include/config/auto.conf.

scripts/setlocalversion already works this way.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-03-14 02:39:11 +09:00
Masahiro Yamada d151e9719f kbuild: merge KBUILD_VMLINUX_{INIT,MAIN} into KBUILD_VMLINUX_OBJS
The top Makefile does not need to export KBUILD_VMLINUX_INIT and
KBUILD_VMLINUX_MAIN separately.

Put every built-in.a into KBUILD_VMLINUX_OBJS. The order of
$(head-y), $(init-y), $(core-y), ... is still retained.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-01-28 09:11:17 +09:00
Masahiro Yamada dee9495303 kbuild: remove top-level built-in.a
The symbol table in the final archive is unneeded; the linker does not
require the symbol table after the --whole-archive option. Every object
file in the archive is included in the link anyway.

Pass thin archives from subdirectories directly to the linker, and
remove the final archiving step.

Fix up the document and comments as well.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
2019-01-28 09:11:17 +09:00
Masahiro Yamada d503ac531a kbuild: rename LDFLAGS to KBUILD_LDFLAGS
Commit a0f97e06a4 ("kbuild: enable 'make CFLAGS=...' to add
additional options to CC") renamed CFLAGS to KBUILD_CFLAGS.

Commit 222d394d30 ("kbuild: enable 'make AFLAGS=...' to add
additional options to AS") renamed AFLAGS to KBUILD_AFLAGS.

Commit 06c5040cdb ("kbuild: enable 'make CPPFLAGS=...' to add
additional options to CPP") renamed CPPFLAGS to KBUILD_CPPFLAGS.

For some reason, LDFLAGS was not renamed.

Using a well-known variable like LDFLAGS may result in accidental
override of the variable.

Kbuild generally uses KBUILD_ prefixed variables for the internally
appended options, so here is one more conversion to sanitize the
naming convention.

I did not touch Makefiles under tools/ since the tools build system
is a different world.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
2018-08-24 08:22:08 +09:00
Masahiro Yamada 534c9f2ec4 kallsyms: remove symbol prefix support
CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX was selected by BLACKFIN, METAG.
They were removed by commit 4ba66a9760 ("arch: remove blackfin port"),
commit bb6fb6dfcc ("metag: Remove arch/metag/"), respectively.

No more architecture enables CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX,
hence the --symbol-prefix option is unnecessary.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
2018-05-17 22:43:36 +09:00
Michael Forney a670b0b4ae kbuild: Use ls(1) instead of stat(1) to obtain file size
stat(1) is not standardized and different implementations have their own
(conflicting) flags for querying the size of a file.

ls(1) provides the same information (value of st.st_size) in the 5th
column, except when the file is a character or block device. This output
is standardized[0]. The -n option turns on -l, which writes lines
formatted like

  "%s %u %s %s %u %s %s\n", <file mode>, <number of links>,
      <owner name>, <group name>, <size>, <date and time>,
      <pathname>

but instead of writing the <owner name> and <group name>, it writes the
numeric owner and group IDs (this avoids /etc/passwd and /etc/group
lookups as well as potential field splitting issues).

The <size> field is specified as "the value that would be returned for
the file in the st_size field of struct stat".

To avoid duplicating logic in several locations in the tree, create
scripts/file-size.sh and update callers to use that instead of stat(1).

[0] http://pubs.opengroup.org/onlinepubs/9699919799/utilities/ls.html#tag_20_73_10

Signed-off-by: Michael Forney <forney@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26 02:01:24 +09:00
Nicholas Piggin f49821ee32 kbuild: rename built-in.o to built-in.a
Incremental linking is gone, so rename built-in.o to built-in.a, which
is the usual extension for archive files.

This patch does two things, first is a simple search/replace:

git grep -l 'built-in\.o' | xargs sed -i 's/built-in\.o/built-in\.a/g'

The second is to invert nesting of nested text manipulations to avoid
filtering built-in.a out from libs-y2:

-libs-y2 := $(filter-out %.a, $(patsubst %/, %/built-in.a, $(libs-y)))
+libs-y2 := $(patsubst %/, %/built-in.a, $(filter-out %.a, $(libs-y)))

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26 02:01:19 +09:00
Nicholas Piggin 6358d6e8b9 kbuild: remove incremental linking option
This removes the old `ld -r` incremental link option, which has not
been selected by any architecture since June 2017.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-26 02:01:19 +09:00
Cao jin a7b151fffb kbuild: drop superfluous GCC_PLUGINS_CFLAGS assignment
GCC_PLUGINS_CFLAGS is already in the environment, so it is superfluous
to add it in commandline of final build of init/.

Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-02 09:20:56 +09:00
Linus Torvalds 09bd7c75e5 Kbuild updates for v4.15
One of the most remarkable improvements in this cycle is, Kbuild is
 now able to cache the result of shell commands.  Some variables are
 expensive to compute, for example, $(call cc-option,...) invokes the
 compiler.  It is not efficient to redo this computation every time,
 even when we are not actually building anything.  Kbuild creates a
 hidden file ".cache.mk" that contains invoked shell commands and
 their results.  The speed-up should be noticeable.
 
 Summary:
 
 - Fix arch build issues (hexagon, sh)
 
 - Clean up various Makefiles and scripts
 
 - Fix wrong usage of {CFLAGS,LDFLAGS}_MODULE in arch Makefiles
 
 - Cache variables that are expensive to compute
 
 - Improve cc-ldopton and ld-option for Clang
 
 - Optimize output directory creation
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Merge tag 'kbuild-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:
 "One of the most remarkable improvements in this cycle is, Kbuild is
  now able to cache the result of shell commands. Some variables are
  expensive to compute, for example, $(call cc-option,...) invokes the
  compiler. It is not efficient to redo this computation every time,
  even when we are not actually building anything. Kbuild creates a
  hidden file ".cache.mk" that contains invoked shell commands and their
  results. The speed-up should be noticeable.

  Summary:

   - Fix arch build issues (hexagon, sh)

   - Clean up various Makefiles and scripts

   - Fix wrong usage of {CFLAGS,LDFLAGS}_MODULE in arch Makefiles

   - Cache variables that are expensive to compute

   - Improve cc-ldopton and ld-option for Clang

   - Optimize output directory creation"

* tag 'kbuild-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (30 commits)
  kbuild: move coccicheck help from scripts/Makefile.help to top Makefile
  sh: decompressor: add shipped files to .gitignore
  frv: .gitignore: ignore vmlinux.lds
  selinux: remove unnecessary assignment to subdir-
  kbuild: specify FORCE in Makefile.headersinst as .PHONY target
  kbuild: remove redundant mkdir from ./Kbuild
  kbuild: optimize object directory creation for incremental build
  kbuild: create object directories simpler and faster
  kbuild: filter-out PHONY targets from "targets"
  kbuild: remove redundant $(wildcard ...) for cmd_files calculation
  kbuild: create directory for make cache only when necessary
  sh: select KBUILD_DEFCONFIG depending on ARCH
  kbuild: fix linker feature test macros when cross compiling with Clang
  kbuild: shrink .cache.mk when it exceeds 1000 lines
  kbuild: do not call cc-option before KBUILD_CFLAGS initialization
  kbuild: Cache a few more calls to the compiler
  kbuild: Add a cache for generated variables
  kbuild: add forward declaration of default target to Makefile.asm-generic
  kbuild: remove KBUILD_SUBDIR_ASFLAGS and KBUILD_SUBDIR_CCFLAGS
  hexagon/kbuild: replace CFLAGS_MODULE with KBUILD_CFLAGS_MODULE
  ...
2017-11-17 17:45:29 -08:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Masahiro Yamada 278ae60403 kbuild: link-vmlinux.sh: simplify .version increment
Since commit 1f2bfbd00e ("kbuild: link of vmlinux moved to a
script"), it is easy to increment .version without using a temporary
file .old_version.

I do not see anybody who creates the .tmp_version.  Probably it is a
left-over of commit 4e25d8bb95 ("[PATCH] kbuild: adjust .version
updating").  Just remove it.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-10-09 23:28:46 +09:00
Nicholas Piggin 3a166fc2d4 kbuild: handle libs-y archives separately from built-in.o archives
The thin archives build currently puts all lib.a and built-in.o
files together and links them with --whole-archive.

This works because thin archives can recursively refer to thin
archives. However some architectures include libgcc.a, which may
not be a thin archive, or it may not be constructed with the "P"
option, in which case its contents do not get linked correctly.

So don't pull .a libs into the root built-in.o archive. These
libs should already have symbol tables and indexes built, so they
can be direct linker inputs. Move them out of the --whole-archive
option, which restore the conditional linking behaviour of lib.a
to thin archives builds.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-06-30 09:03:03 +09:00
Nicholas Piggin 9a6cfca4f4 kbuild: thin archives use P option to ar
The P option makes ar do full path name matching and can prevent ar
from discarding files with duplicate names in some cases of creating
thin archives from thin archives. The sh architecture in particular
loses some object files from its kernel/cpu/sh*/ directories without
this option.

This could be a bug in binutils ar, but the P option should not cause
any negative effects so it is safe to use to work around this with.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-06-30 09:03:03 +09:00
Nicholas Piggin 1328a1ae0e kbuild: thin archives final link close --whole-archives option
Close the --whole-archives option with --no-whole-archive. Some
architectures end up including additional .o and files multiple
times after this, and they get duplicate symbols when they are
brought under the --whole-archives option.

This matches more closely with the incremental final link.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-06-30 09:03:02 +09:00
Nicholas Piggin abac4c8973 kbuild: minor improvement for thin archives build
The root built-in.o archive is currently generated before all object
files are built for the final link, due to final build of init/ after
version update. In practice it seems like it doesn't matter because
the archive symbol table does not change, but it is more logical to
create the final archive as the last step.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-11-29 15:58:57 +01:00
Nicholas Piggin 7e2b37c971 kbuild: kallsyms allow 3-pass generation if symbols size has changed
kallsyms generation is not foolproof, due to some linkers adding
symbols (e.g., branch trampolines) when a binary size changes.
Have it attempt a 3rd pass automatically if the kallsyms size changes
in the 2nd pass.

This allows powerpc64 allyesconfig to build without adding another
pass when it's not required.

This can be solved other ways by directing the linker not to add labels
on branch stubs, or to move kallsyms near the end of the image. The
former is undesirable for debugging/tracing, and the latter is a more
significant change that requires more testing and review.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-11-29 15:53:19 +01:00
Stephen Rothwell a5967db9af kbuild: allow architectures to use thin archives instead of ld -r
ld -r is an incremental link used to create built-in.o files in build
subdirectories. It produces relocatable object files containing all
its input files, and these are are then pulled together and relocated
in the final link. Aside from the bloat, this constrains the final
link relocations, which has bitten large powerpc builds with
unresolvable relocations in the final link.

Alan Modra has recommended the kernel use thin archives for linking.
This is an alternative and means that the linker has more information
available to it when it links the kernel.

This patch enables a config option architectures can select, which
causes all built-in.o files to be built as thin archives. built-in.o
files in subdirectories do not get symbol table or index attached,
which improves speed and size. The final link pass creates a
built-in.o archive in the root output directory which includes the
symbol table and index. The linker then uses takes this file to link.

The --whole-archive linker option is required, because the linker now
has visibility to every individual object file, and it will otherwise
just completely avoid including those without external references
(consider a file with EXPORT_SYMBOL or initcall or hardware exceptions
as its only entry points). The traditional built works "by luck" as
built-in.o files are large enough that they're going to get external
references. However this optimisation is unpredictable for the kernel
(due to above external references), ineffective at culling unused, and
costly because the .o files have to be searched for references.
Superior alternatives for link-time culling should be used instead.

Build characteristics for inclink vs thinarc, on a small powerpc64le
pseries VM with a modest .config:

                                  inclink       thinarc
sizes
vmlinux                        15 618 680    15 625 028
sum of all built-in.o          56 091 808     1 054 334
sum excluding root built-in.o                   151 430

find -name built-in.o | xargs rm ; time make vmlinux
real                              22.772s       21.143s
user                              13.280s       13.430s
sys                                4.310s        2.750s

- Final kernel pulled in only about 6K more, which shows how
  ineffective the object file culling is.
- Build performance looks improved due to less pagecache activity.
  On IO constrained systems it could be a bigger win.
- Build size saving is significant.

Side note, the toochain understands archives, so there's some tricks,
$ ar t built-in.o          # list all files you linked with
$ size built-in.o          # and their sizes
$ objdump -d built-in.o    # disassembly (unrelocated) with filenames

Implementation by sfr, minor tweaks by npiggin.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-09-09 10:31:19 +02:00
Emese Revfy 6b90bd4ba4 GCC plugin infrastructure
This patch allows to build the whole kernel with GCC plugins. It was ported from
grsecurity/PaX. The infrastructure supports building out-of-tree modules and
building in a separate directory. Cross-compilation is supported too.
Currently the x86, arm, arm64 and uml architectures enable plugins.

The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory
there. The plugins compile with these options:
 * -fno-rtti: gcc is compiled with this option so the plugins must use it too
 * -fno-exceptions: this is inherited from gcc too
 * -fasynchronous-unwind-tables: this is inherited from gcc too
 * -ggdb: it is useful for debugging a plugin (better backtrace on internal
    errors)
 * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h)
 * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version
    variable, plugin-version.h)

The infrastructure introduces a new Makefile target called gcc-plugins. It
supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script
chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++).
This script also checks the availability of the included headers in
scripts/gcc-plugins/gcc-common.h.

The gcc-common.h header contains frequently included headers for GCC plugins
and it has a compatibility layer for the supported gcc versions.

The gcc-generate-*-pass.h headers automatically generate the registration
structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes.

Note that 'make clean' keeps the *.so files (only the distclean or mrproper
targets clean all) because they are needed for out-of-tree modules.

Based on work created by the PaX Team.

Signed-off-by: Emese Revfy <re.emese@gmail.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-06-07 22:57:10 +02:00
Ard Biesheuvel d4ffe41819 ARM: 8552/1: kallsyms: remove special lower address limit for CONFIG_ARM
Now that we no longer emit .stubs symbols into a section VMA loaded
at absolute address 0x1000, we can drop the ARM-specific override that
sets a lower limit based on CONFIG_PAGE_OFFSET, below which symbols are
filtered from the kallsyms output.

Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Chris Brandt <chris.brandt@renesas.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-04-07 21:57:15 +01:00
Linus Torvalds 2162b80fca Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild updates from Michal Marek:

 - make dtbs_install fix

 - Error handling fix fixdep and link-vmlinux.sh

 - __UNIQUE_ID fix for clang

 - Fix for if_changed_* to suppress the "is up to date." message

 - The kernel is built with -Werror=incompatible-pointer-types

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  kbuild: Add option to turn incompatible pointer check into error
  kbuild: suppress annoying "... is up to date." message
  kbuild: fixdep: Check fstat(2) return value
  scripts/link-vmlinux.sh: force error on kallsyms failure
  Kbuild: provide a __UNIQUE_ID for clang
  dtbsinstall: don't move target directory out of the way
2016-03-24 19:26:47 -07:00
Ard Biesheuvel 2213e9a66b kallsyms: add support for relative offsets in kallsyms address table
Similar to how relative extables are implemented, it is possible to emit
the kallsyms table in such a way that it contains offsets relative to
some anchor point in the kernel image rather than absolute addresses.

On 64-bit architectures, it cuts the size of the kallsyms address table
in half, since offsets between kernel symbols can typically be expressed
in 32 bits.  This saves several hundreds of kilobytes of permanent
.rodata on average.  In addition, the kallsyms address table is no
longer subject to dynamic relocation when CONFIG_RELOCATABLE is in
effect, so the relocation work done after decompression now doesn't have
to do relocation updates for all these values.  This saves up to 24
bytes (i.e., the size of a ELF64 RELA relocation table entry) per value,
which easily adds up to a couple of megabytes of uncompressed __init
data on ppc64 or arm64.  Even if these relocation entries typically
compress well, the combined size reduction of 2.8 MB uncompressed for a
ppc64_defconfig build (of which 2.4 MB is __init data) results in a ~500
KB space saving in the compressed image.

Since it is useful for some architectures (like x86) to retain the
ability to emit absolute values as well, this patch also adds support
for capturing both absolute and relative values when
KALLSYMS_ABSOLUTE_PERCPU is in effect, by emitting absolute per-cpu
addresses as positive 32-bit values, and addresses relative to the
lowest encountered relative symbol as negative values, which are
subtracted from the runtime address of this base symbol to produce the
actual address.

Support for the above is enabled by default for all architectures except
IA-64 and Tile-GX, whose symbols are too far apart to capture in this
manner.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Kees Cook <keescook@chromium.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15 16:55:16 -07:00
Ard Biesheuvel 4d5d5664c9 x86: kallsyms: disable absolute percpu symbols on !SMP
scripts/kallsyms.c has a special --absolute-percpu command line option
which deals with the zero based per cpu offsets that are used when
building for SMP on x86_64.  This means that the option should only be
passed in that case, so add a Kconfig symbol with the correct predicate,
and use that instead.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Kees Cook <keescook@chromium.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15 16:55:16 -07:00
Ard Biesheuvel a043934207 scripts/link-vmlinux.sh: force error on kallsyms failure
Since the output of the invocation of scripts/kallsyms is piped directly
into the assembler, error messages it emits are visible on stderr, but
a non-zero return code is ignored, and the build simply proceeds in that
case. However, the resulting kernel is most likely broken, and will crash
at boot.

So instead, capture the output of kallsyms in a separate .S file, and pass
that to the assembler in a separate step.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-02-08 20:45:09 +01:00
Vegard Nossum a7df4716d1 um: link with -lpthread
Similarly to commit fb1770aa78, with gcc 5
on Ubuntu and CONFIG_STATIC_LINK=y I was seeing these linker errors:

/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/librt.a(timer_create.o): In function `__timer_create_new':
(.text+0xcd): undefined reference to `pthread_once'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/librt.a(timer_create.o): In function `__timer_create_new':
(.text+0x126): undefined reference to `pthread_attr_init'
/usr/lib/gcc/x86_64-linux-gnu/5/../../../x86_64-linux-gnu/librt.a(timer_create.o): In function `__timer_create_new':
(.text+0x168): undefined reference to `pthread_attr_setdetachstate'
[...]

Obviously we also need -lpthread for librt.a.

Cc: stable@vger.kernel.org # 4.4
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2016-01-10 21:49:48 +01:00
Lorenzo Colitti fb1770aa78 arch: um: fix error when linking vmlinux.
On gcc Ubuntu 4.8.4-2ubuntu1~14.04, linking vmlinux fails with:

arch/um/os-Linux/built-in.o: In function `os_timer_create':
/android/kernel/android/arch/um/os-Linux/time.c:51: undefined reference to `timer_create'
arch/um/os-Linux/built-in.o: In function `os_timer_set_interval':
/android/kernel/android/arch/um/os-Linux/time.c:84: undefined reference to `timer_settime'
arch/um/os-Linux/built-in.o: In function `os_timer_remain':
/android/kernel/android/arch/um/os-Linux/time.c:109: undefined reference to `timer_gettime'
arch/um/os-Linux/built-in.o: In function `os_timer_one_shot':
/android/kernel/android/arch/um/os-Linux/time.c:132: undefined reference to `timer_settime'
arch/um/os-Linux/built-in.o: In function `os_timer_disable':
/android/kernel/android/arch/um/os-Linux/time.c:145: undefined reference to `timer_settime'

This is because -lrt appears in the generated link commandline
after arch/um/os-Linux/built-in.o. Fix this by removing -lrt from
arch/um/Makefile and adding it to the UM-specific section of
scripts/link-vmlinux.sh.

Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2015-12-08 22:25:13 +01:00
Maxime Coquelin cc84753052 scripts: link-vmlinux: Don't pass page offset to kallsyms if XIP Kernel
When Kernel is executed in place from ROM, the symbol addresses can be
lower than the page offset.

Tested-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Tested-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2015-05-21 19:17:44 +08:00
Sylvain BERTRAND ab160dbbc4 scripts: fix link-vmlinux.sh bash-ism
While building linux with dash shell:
  LINK    vmlinux
trap: SIGHUP: bad trap
/src/linux-4.0/Makefile:933: recipe for target 'vmlinux' failed
make[1]: *** [vmlinux] Error 1

See the following document for behavior of posix shell trap instruction:
http://pubs.opengroup.org/onlinepubs/000095399/utilities/trap.html

Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sylvain BERTRAND <sylvain.bertrand@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2015-05-07 12:42:03 +02:00
Michal Marek 06ed5c2bfa kbuild: Make scripts executable
The Makefiles call the respective interpreter explicitly, but this makes
it easier to use the scripts manually.

Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-08-20 16:03:45 +02:00
Rusty Russell c6bda7c988 kallsyms: fix percpu vars on x86-64 with relocation.
x86-64 has a problem: per-cpu variables are actually represented by
their absolute offsets within the per-cpu area, but the symbols are
not emitted as absolute.  Thus kallsyms naively creates them as offsets
from _text, meaning their values change if the kernel is relocated
(especially noticeable with CONFIG_RANDOMIZE_BASE):

 $ egrep ' (gdt_|_(stext|_per_cpu_))' /root/kallsyms.nokaslr
 0000000000000000 D __per_cpu_start
 0000000000004000 D gdt_page
 0000000000014280 D __per_cpu_end
 ffffffff810001c8 T _stext
 ffffffff81ee53c0 D __per_cpu_offset
 $ egrep ' (gdt_|_(stext|_per_cpu_))' /root/kallsyms.kaslr1
 000000001f200000 D __per_cpu_start
 000000001f204000 D gdt_page
 000000001f214280 D __per_cpu_end
 ffffffffa02001c8 T _stext
 ffffffffa10e53c0 D __per_cpu_offset

Making them absolute symbols is the Right Thing, but requires fixes to
the relocs tool.  So for the moment, we add a --absolute-percpu option
which makes them absolute from a kallsyms perspective:

 $ egrep ' (gdt_|_(stext|_per_cpu_))' /proc/kallsyms # no KASLR
 0000000000000000 A __per_cpu_start
 000000000000a000 A gdt_page
 0000000000013040 A __per_cpu_end
 ffffffff802001c8 T _stext
 ffffffff8099b180 D __per_cpu_offset
 ffffffff809a3000 D __per_cpu_load
 $ egrep ' (gdt_|_(stext|_per_cpu_))' /proc/kallsyms # With KASLR
 0000000000000000 A __per_cpu_start
 000000000000a000 A gdt_page
 0000000000013040 A __per_cpu_end
 ffffffff89c001c8 T _stext
 ffffffff8a39d180 D __per_cpu_offset
 ffffffff8a3a5000 D __per_cpu_load

Based-on-the-original-screenplay-by: Andy Honig <ahonig@google.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Kees Cook <keescook@chromium.org>
2014-03-17 14:55:27 +10:30
Ming Lei 7122c3e915 scripts/link-vmlinux.sh: only filter kernel symbols for arm
Actually CONFIG_PAGE_OFFSET isn't same with PAGE_OFFSET, so
it isn't easy to figue out PAGE_OFFSET defined in header
file from scripts.

Because CONFIG_PAGE_OFFSET may not be defined in some ARCHs(
64bit ARCH), or defined as bogus value in !MMU case, so
this patch only applys the filter on ARM when CONFIG_PAGE_OFFSET
is defined as the original problem is only on ARM.

Cc: <stable@vger.kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Fixes: f6537f2f0e
Singed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-12-10 16:49:19 +10:30
Ming Lei f6537f2f0e scripts/kallsyms: filter symbols not in kernel address space
This patch uses CONFIG_PAGE_OFFSET to filter symbols which
are not in kernel address space because these symbols are
generally for generating code purpose and can't be run at
kernel mode, so we needn't keep them in /proc/kallsyms.

For example, on ARM there are some symbols which may be
linked in relocatable code section, then perf can't parse
symbols any more from /proc/kallsyms, this patch fixes the
problem (introduced b9b32bf70f)

Cc: Russell King <linux@arm.linux.org.uk>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: stable@vger.kernel.org
2013-11-02 09:13:02 +10:30
Rusty Russell b92021b09d CONFIG_SYMBOL_PREFIX: cleanup.
We have CONFIG_SYMBOL_PREFIX, which three archs define to the string
"_".  But Al Viro broke this in "consolidate cond_syscall and
SYSCALL_ALIAS declarations" (in linux-next), and he's not the first to
do so.

Using CONFIG_SYMBOL_PREFIX is awkward, since we usually just want to
prefix it so something.  So various places define helpers which are
defined to nothing if CONFIG_SYMBOL_PREFIX isn't set:

1) include/asm-generic/unistd.h defines __SYMBOL_PREFIX.
2) include/asm-generic/vmlinux.lds.h defines VMLINUX_SYMBOL(sym)
3) include/linux/export.h defines MODULE_SYMBOL_PREFIX.
4) include/linux/kernel.h defines SYMBOL_PREFIX (which differs from #7)
5) kernel/modsign_certificate.S defines ASM_SYMBOL(sym)
6) scripts/modpost.c defines MODULE_SYMBOL_PREFIX
7) scripts/Makefile.lib defines SYMBOL_PREFIX on the commandline if
   CONFIG_SYMBOL_PREFIX is set, so that we have a non-string version
   for pasting.

(arch/h8300/include/asm/linkage.h defines SYMBOL_NAME(), too).

Let's solve this properly:
1) No more generic prefix, just CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX.
2) Make linux/export.h usable from asm.
3) Define VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR().
4) Make everyone use them.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Tested-by: James Hogan <james.hogan@imgtec.com> (metag)
2013-03-15 15:09:43 +10:30
Michal Marek 423a8155fa kbuild: Fix reading of .config in link-vmlinux.sh
The shell '.' command is not required to search the current directory as
a fallback and in fact newer versions of bash in sh-mode do not do this.
Force reading the file from the current directory if $KCONFIG_CONFIG
contains no '/'.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2013-02-25 16:14:48 +01:00
Michael Grzeschik 03b25b47e0 scripts/link-vmlinux.sh: source variables from KCONFIG_CONFIG
Its possible to superseed the config file with KCONFIG_CONFIG and have
completely no .config in the tree. The current script is sourcing
.config in every case, so the kernel will never build succesfully. This
patch fixes that issue by sourcing KCONFIG_CONFIG instead.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2013-02-22 10:37:18 +01:00
Linus Torvalds 2a1497c3c4 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lliubbo/blackfin
Pull blackfin updates from Bob Liu:
 "One kbuild and a smp build fix."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lliubbo/blackfin:
  kbuild: add symbol prefix arg to kallsyms
  blackfin: smp: adapt to generic smp helpers
2012-09-12 07:12:53 +08:00
James Hogan 6895f97e15 kbuild: add symbol prefix arg to kallsyms
Commit 1f2bfbd00e ("kbuild: link of
vmlinux moved to a script") introduced in v3.5-rc1 broke kallsyms on
architectures which have symbol prefixes.

The --symbol-prefix argument used to be added to the KALLSYMS command
line from the architecture Makefile, however this isn't picked up by the
new scripts/link-vmlinux.sh. This resulted in symbols like
kallsyms_addresses being added which weren't correctly overriding the
weak symbols such as _kallsyms_addresses. These could then trigger
BUG_ONs in kallsyms code.

This is fixed by removing the KALLSYMS addition from the architecture
Makefile, and using CONFIG_SYMBOL_PREFIX in the link-vmlinux.sh script
to determine whether to add the --symbol-prefix argument.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Bob Liu <lliubbo@gmail.com>
2012-09-11 10:25:12 +08:00
Michal Marek 367e43c50d link-vmlinux.sh: Fix stray "echo" in error message
Reported-by: Jan Engelhardt <jengelh@inai.de>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2012-08-10 11:55:11 +02:00
Michal Marek 5369f55021 kbuild: Print errors to stderr
... at least in the top-level Makefile and scripts/link-vmlinux.sh.
There are some more instances of the 'echo <error>; exit 1' pattern in
some arch Makefiles and kconfig.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2012-07-07 23:33:31 +02:00
Linus Torvalds 1347a2cebc Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild updates from Michal Marek.

Fixed up nontrivial merge conflict in Makefile as per Stephen Rothwell
and linux-next (and trivial arch/sparc/Makefile changes due to removed
sparc32 logic).

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  mips: Fix KBUILD_CPPFLAGS definition
  kbuild: fix ia64 link
  kbuild: document KBUILD_LDS, KBUILD_VMLINUX_{INIT,MAIN} and LDFLAGS_vmlinux
  kbuild: link of vmlinux moved to a script
  kbuild: refactor final link of sparc32
  kbuild: drop unused KBUILD_VMLINUX_OBJS from top-level Makefile
  kbuild: Makefile: remove unnecessary check for m68knommu ARCH
2012-05-28 10:32:28 -07:00
Sam Ravnborg 00e6c28c68 kbuild: fix ia64 link
ia64 build failed like this:

  CC      init/version.o
  LD      init/built-in.o
  KSYM    .tmp_kallsyms1.o
ld: .tmp_kallsyms1.o: linking constant-gp files with non-constant-gp files
ld: failed to merge target specific data of file .tmp_kallsyms1.o
make: *** [vmlinux] Error 1

This was introduced when link of vmlinux was migrated to a script.
Add missing option to as to fix this.

Reported-by: Tony Luck <tony.luck@gmail.com>
Tested-by: Tony Luck <tony.luck@gmail.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2012-05-10 14:09:21 +02:00
Sam Ravnborg 1f2bfbd00e kbuild: link of vmlinux moved to a script
Move the final link of vmlinux to a script to improve
readability and maintainability of the code.

The Makefile fragments used to link vmlinux has over the
years seen far too many changes and the logic had become
hard to follow.

As the process by nature is serialized there was
nothing gained including this in the Makefile.

"um" has special link requirments - and the
only way to handle this was to hard-code the linking
of "um" in the script.
This was better than trying to modularize it only for the
benefit of "um" anyway.

The shell script has been improved after input from:
Arnaud Lacombe <lacombar@gmail.com>
Nick Bowler <nbowler@elliptictech.com>

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Arnaud Lacombe <lacombar@gmail.com>
Cc: Nick Bowler <nbowler@elliptictech.com>
Cc: Richard Weinberger <richard@nod.at>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2012-05-05 21:19:33 +02:00