Commit Graph

1962 Commits

Author SHA1 Message Date
Jiri Olsa
017dab341e bpf: Check CONFIG_BPF option for resolve_btfids
Currently all the resolve_btfids 'users' are under CONFIG_BPF
code, so if we have CONFIG_BPF disabled, resolve_btfids will
fail, because there's no data to resolve.

Disabling resolve_btfids if there's CONFIG_BPF disabled,
so we won't fail such builds.

Suggested-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200923185735.3048198-1-jolsa@kernel.org
2020-09-23 12:43:04 -07:00
Linus Torvalds
ba4f184e12 Linux 5.9-rc6 2020-09-20 16:33:55 -07:00
Linus Torvalds
856deb866d Linux 5.9-rc5 2020-09-13 16:06:00 -07:00
Linus Torvalds
612ab8ad64 Livepatching changes for 5.9-rc5
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEESH4wyp42V4tXvYsjUqAMR0iAlPIFAl9V6lcACgkQUqAMR0iA
 lPId9hAAoGAOKfugHd+uGqEPwo7fA5ZJuuMTME0WN4u6IideREYFTK7zZSt6Rv9D
 oqJhy5BDFhCjkhX3fvXVvupX7H6jCn7qZGiZi/CJNustjQa1lR7OzQrYnmmwUklW
 JzReiowbEurp/s74ASfftO2KaltZ7iqBXf7nG4Cdc6tSuLBTFGYw4Kq9yinhnTBu
 OtydiY1dbzjQdEVLej919HFuC/ycVJ8hV59m4FUnONHXOp3vHRKBWW8zd4dOD4Ej
 Nx3rRr8aK2pUUqavS5KnTnn8LyhUuzho2mXDigJ6s3uUY95iol7GFcfyt+5y42Cm
 6FjCjvPQXHk1VBqDlGhwhbE+Ahi5Xhn95qpIE10/pKjSxv4JAoyERBEboSrbb45r
 ISnE7V5jzVSyoaUGVmKIFf9/gczmp0OqaXgh8hVNyRuSxrtR0r5VpyZAHF0PSz9K
 zY5HxuhRKba9gYtJFkp9sCngu9XC/pGMOkMiqWYTX3QurH3laoGzl1ogNvl6gSSj
 7sgbAf21TkqD+Pw3/IMiAqopfrD3wrSFRKSn6leUL62UFgJWS8vjfJpeIphbzywZ
 43J5s6HcJxhlvGiT7b2Xv0FuP9IdHpqqmS/JkgA9zK5U6qlpQ7hPRni8GS5zdbej
 I9xL7/pzg9Xt5V5y44hC1ojIXpNLQbvLiATbB1oJwdpvsWCjvaU=
 =Udfx
 -----END PGP SIGNATURE-----

Merge tag 'livepatching-for-5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching

Pull livepatching fix from Petr Mladek:
 "Workaround for 'unreachable instruction' objtool warnings that happen
  with some compiler versions"

* tag 'livepatching-for-5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching:
  Revert "kbuild: use -flive-patching when CONFIG_LIVEPATCH is enabled"
2020-09-08 10:52:59 -07:00
Linus Torvalds
f4d51dffc6 Linux 5.9-rc4 2020-09-06 17:11:40 -07:00
Josh Poimboeuf
318af7b80b Revert "kbuild: use -flive-patching when CONFIG_LIVEPATCH is enabled"
Use of the new -flive-patching flag was introduced with the following
commit:

  43bd3a95c9 ("kbuild: use -flive-patching when CONFIG_LIVEPATCH is enabled")

This flag has several drawbacks:

- It disables some optimizations, so it can have a negative effect on
  performance.

- According to the GCC documentation it's not compatible with LTO, which
  will become a compatibility issue as LTO support gets upstreamed in
  the kernel.

- It was intended to be used for source-based patch generation tooling,
  as opposed to binary-based patch generation tooling (e.g.,
  kpatch-build).  It probably should have at least been behind a
  separate config option so as not to negatively affect other livepatch
  users.

- Clang doesn't have the flag, so as far as I can tell, this method of
  generating patches is incompatible with Clang, which like LTO is
  becoming more mainstream.

- It breaks GCC's implicit noreturn detection for local functions.  This
  is the cause of several "unreachable instruction" objtool warnings.

- The broken noreturn detection is an obvious GCC regression, but we
  haven't yet gotten GCC developers to acknowledge that, which doesn't
  inspire confidence in their willingness to keep the feature working as
  optimizations are added or changed going forward.

- While there *is* a distro which relies on this flag for their distro
  livepatch module builds, there's not a publicly documented way to
  create safe livepatch modules with it.  Its use seems to be based on
  tribal knowledge.  It serves no benefit to those who don't know how to
  use it.

  (In fact, I believe the current livepatch documentation and samples
  are misleading and dangerous, and should be corrected.  Or at least
  amended with a disclaimer.  But I don't feel qualified to make such
  changes.)

Also, we have an idea for using objtool to detect function changes,
which could potentially obsolete the need for this flag anyway.

At this point the flag has no benefits for upstream which would
counteract the above drawbacks.  Revert it until it becomes more ready.

This reverts commit 43bd3a95c9.

Fixes: 43bd3a95c9 ("kbuild: use -flive-patching when CONFIG_LIVEPATCH is enabled")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/696262e997359666afa053fe7d1a9fb2bb373964.1595010490.git.jpoimboe@redhat.com
2020-09-03 11:24:27 +02:00
Linus Torvalds
f75aef392f Linux 5.9-rc3 2020-08-30 16:01:54 -07:00
Nathan Huckleberry
6ad7cbc015 Makefile: Add clang-tidy and static analyzer support to makefile
This patch adds clang-tidy and the clang static-analyzer as make
targets. The goal of this patch is to make static analysis tools
usable and extendable by any developer or researcher who is familiar
with basic c++.

The current static analysis tools require intimate knowledge of the
internal workings of the static analysis. Clang-tidy and the clang
static analyzers expose an easy to use api and allow users unfamiliar
with clang to write new checks with relative ease.

===Clang-tidy===

Clang-tidy is an easily extendable 'linter' that runs on the AST.
Clang-tidy checks are easy to write and understand. A check consists of
two parts, a matcher and a checker. The matcher is created using a
domain specific language that acts on the AST
(https://clang.llvm.org/docs/LibASTMatchersReference.html).  When AST
nodes are found by the matcher a callback is made to the checker. The
checker can then execute additional checks and issue warnings.

Here is an example clang-tidy check to report functions that have calls
to local_irq_disable without calls to local_irq_enable and vice-versa.
Functions flagged with __attribute((annotation("ignore_irq_balancing")))
are ignored for analysis. (https://reviews.llvm.org/D65828)

===Clang static analyzer===

The clang static analyzer is a more powerful static analysis tool that
uses symbolic execution to find bugs. Currently there is a check that
looks for potential security bugs from invalid uses of kmalloc and
kfree. There are several more general purpose checks that are useful for
the kernel.

The clang static analyzer is well documented and designed to be
extensible.
(https://clang-analyzer.llvm.org/checker_dev_manual.html)
(https://github.com/haoNoQ/clang-analyzer-guide/releases/download/v0.1/clang-analyzer-guide-v0.1.pdf)

The main draw of the clang tools is how accessible they are. The clang
documentation is very nice and these tools are built specifically to be
easily extendable by any developer. They provide an accessible method of
bug-finding and research to people who are not overly familiar with the
kernel codebase.

Signed-off-by: Nathan Huckleberry <nhuck@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-08-27 00:44:33 +09:00
Masahiro Yamada
3d32285fa9 kbuild: wire up the build rule of compile_commands.json to Makefile
Currently, you need to manually run scripts/gen_compile_commands.py
to create compile_commands.json. It parses all the .*.cmd files found
under the specified directory.

If you rebuild the kernel over again without 'make clean',
.*.cmd files from older builds will create stale entries in
compile_commands.json.

This commit wires up the compile_commands.json rule to Makefile, and
makes it parse only the .*.cmd files involved in the current build.

Pass $(KBUILD_VMLINUX_OBJS), $(KBUILD_VMLINUX_LIBS), and modules.order
to the script. The objects or archives linked to vmlinux are listed in
$(KBUILD_VMLINUX_OBJS) or $(KBUILD_VMLINUX_LIBS). All the modules are
listed in modules.order.

You can create compile_commands.json from Make:

  $ make -j$(nproc) CC=clang compile_commands.json

You can also build vmlinux, modules, and compile_commands.json all
together in a single command:

  $ make -j$(nproc) CC=clang all compile_commands.json

It works for M= builds as well. In this case, compile_commands.json
is created in the top directory of the external module.

This is convenient, but it has a drawback; the coverage of the
compile_commands.json is reduced because only the objects linked to
vmlinux or modules are handled. For example, the following C files are
not included in the compile_commands.json:

 - Decompressor source files (arch/*/boot/)
 - VDSO source files
 - C files used to generate intermediates (e.g. kernel/bounds.c)
 - Standalone host programs

I think it is fine for most developers because our main interest is
the kernel-space code.

If you want to cover all the compiled C files, please build the kernel,
then run the script manually as you did before:

  $ make clean    # if you want to remove stale .cmd files [optional]
  $ make -j$(nproc) CC=clang
  $ scripts/gen_compile_commands.py

Here is a note for out-of-tree builds. 'make compile_commands.json'
works with O= option, but please notice compile_commands.json is
created in the object tree instead of the source tree.

Some people may want to have compile_commands.json in the source tree
because Clang Tools searches for it through all parent paths of the
first input source file.

However, you cannot do this for O= builds. Kbuild should never generate
any build artifact in the source tree when O= is given because the
source tree might be read-only. Any write attempt to the source tree
is monitored and the violation may be reported. See the commit log of
8ef14c2c41.

So, the only possible way is to create compile_commands.json in the
object tree, then specify '-p <build-path>' when you use clang-check,
clang-tidy, etc.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
2020-08-27 00:44:33 +09:00
Masahiro Yamada
23cd88c913 kbuild: hide commands to run Kconfig, and show short log for syncconfig
Some targets (localyesconfig, localmodconfig, defconfig) hide the
command running, but the others do not.

Users know which Kconfig flavor they are running, so it is OK to hide
the command. Add $(Q) to all commands consistently. If you want to see
the full command running, pass V=1 from the command line.

syncconfig is the exceptional case, which occurs without explicit
command invocation by the user. Display the Kbuild-style log for it.
The ugly bare log will go away.

[Before]

scripts/kconfig/conf  --syncconfig Kconfig

[After]

  SYNC    include/config/auto.conf

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-08-27 00:44:33 +09:00
Sedat Dilek
695afd3d7d kbuild: Simplify DEBUG_INFO Kconfig handling
While playing with [1] I saw that the handling
of CONFIG_DEBUG_INFO can be simplified.

[1] https://patchwork.kernel.org/patch/11716107/

Signed-off-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-08-27 00:44:33 +09:00
Linus Torvalds
d012a7190f Linux 5.9-rc2 2020-08-23 14:08:43 -07:00
Masahiro Yamada
efbf97265f kbuild: remove redundant patterns in filter/filter-out
The '%' in filter/filter-out matches to any number of any characters,
including empty string.

So, '%config' matches to 'config', and '%install' to 'install'.

Drop the redundant patterns.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-08-18 20:16:46 +09:00
Linus Torvalds
9123e3a74e Linux 5.9-rc1 2020-08-16 13:04:57 -07:00
Feng Tang
09c60546f0 ./Makefile: add debug option to enable function aligned on 32 bytes
Recently 0day reported many strange performance changes (regression or
improvement), in which there was no obvious relation between the culprit
commit and the benchmark at the first look, and it causes people to doubt
the test itself is wrong.

Upon further check, many of these cases are caused by the change to the
alignment of kernel text or data, as whole text/data of kernel are linked
together, change in one domain may affect alignments of other domains.

gcc has an option '-falign-functions=n' to force text aligned, and with
that option enabled, some of those performance changes will be gone, like
[1][2][3].

Add this option so that developers and 0day can easily find performance
bump caused by text alignment change, as tracking these strange bump is
quite time consuming.  Though it can't help in other cases like data
alignment changes like [4].

Following is some size data for v5.7 kernel built with a RHEL config used
in 0day:

    text      data      bss	 dec	   filename
  19738771  13292906  5554236  38585913	 vmlinux.noalign
  19758591  13297002  5529660  38585253	 vmlinux.align32

Raw vmlinux size in bytes:

	v5.7		v5.7+align32
	253950832	254018000	+0.02%

Some benchmark data, most of them have no big change:

  * hackbench:		[ -1.8%,  +0.5%]

  * fsmark:		[ -3.2%,  +3.4%]  # ext4/xfs/btrfs

  * kbuild:		[ -2.0%,  +0.9%]

  * will-it-scale:	[ -0.5%,  +1.8%]  # mmap1/pagefault3

  * netperf:
    - TCP_CRR		[+16.6%, +97.4%]
    - TCP_RR		[-18.5%,  -1.8%]
    - TCP_STREAM	[ -1.1%,  +1.9%]

[1] https://lore.kernel.org/lkml/20200114085637.GA29297@shao2-debian/
[2] https://lore.kernel.org/lkml/20200330011254.GA14393@feng-iot/
[3] https://lore.kernel.org/lkml/1d98d1f0-fe84-6df7-f5bd-f4cb2cdb7f45@intel.com/
[4] https://lore.kernel.org/lkml/20200205123216.GO12867@shao2-debian/

Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@intel.com>
Link: http://lkml.kernel.org/r/1595475001-90945-1-git-send-email-feng.tang@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-12 10:57:59 -07:00
Linus Torvalds
fc80c51fd4 Kbuild updates for v5.9
- run the checker (e.g. sparse) after the compiler
 
  - remove unneeded cc-option tests for old compiler flags
 
  - fix tar-pkg to install dtbs
 
  - introduce ccflags-remove-y and asflags-remove-y syntax
 
  - allow to trace functions in sub-directories of lib/
 
  - introduce hostprogs-always-y and userprogs-always-y syntax
 
  - various Makefile cleanups
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCgAzFiEEbmPs18K1szRHjPqEPYsBB53g2wYFAl8wJXEVHG1hc2FoaXJv
 eUBrZXJuZWwub3JnAAoJED2LAQed4NsGMGEP/0jDq/WafbfPN0aU83EqEWLt/sKg
 bluzmf/6HGx3XVRnuAzsHNNqysUx77WJiDsU/jbC/zdH8Iox3Sc1diE2sELLNAfY
 iJmQ8NBPggyU74aYG3OJdpDjz8T9EX/nVaYrjyFlbuXElM+Qvo8Z4Fz6NpWqKWlA
 gU+yGxEPPdX6MLHcSPSIu1hGWx7UT4fgfx3zDFTI2qvbQgQjKtzyTjAH5Cm3o87h
 rfomvHSSoAUg+Fh1LediRh1tJlkdVO+w7c+LNwCswmdBtkZuxecj1bQGUTS8GaLl
 CCWOKYfWp0KsVf1veXNNNaX/ecbp+Y34WErFq3V9Fdq5RmVlp+FPSGMyjDMRiQ/p
 LGvzbJLPpG586MnK8of0dOj6Es6tVPuq6WH2HuvsyTGcZJDpFTTxRcK3HDkE8ig6
 ZtuM3owB/Mep8IzwY2yWQiDrc7TX5Fz8S4hzGPU1zG9cfj4VT6TBqHGAy1Eql/0l
 txj6vJpnbQSdXiIX8MIU3yH35Y7eW3JYWgspTZH5Woj1S/wAWwuG93Fuuxq6mQIJ
 q6LSkMavtOfuCjOA9vJBZewpKXRU6yo0CzWNL/5EZ6z/r/I+DGtfb/qka8oYUDjX
 9H0cecL37AQxDHRPTxCZDQF0TpYiFJ6bmnMftK9NKNuIdvsk9DF7UBa3EdUNIj38
 yKS3rI7Lw55xWuY3
 =bkNQ
 -----END PGP SIGNATURE-----

Merge tag 'kbuild-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - run the checker (e.g. sparse) after the compiler

 - remove unneeded cc-option tests for old compiler flags

 - fix tar-pkg to install dtbs

 - introduce ccflags-remove-y and asflags-remove-y syntax

 - allow to trace functions in sub-directories of lib/

 - introduce hostprogs-always-y and userprogs-always-y syntax

 - various Makefile cleanups

* tag 'kbuild-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: stop filtering out $(GCC_PLUGINS_CFLAGS) from cc-option base
  kbuild: include scripts/Makefile.* only when relevant CONFIG is enabled
  kbuild: introduce hostprogs-always-y and userprogs-always-y
  kbuild: sort hostprogs before passing it to ifneq
  kbuild: move host .so build rules to scripts/gcc-plugins/Makefile
  kbuild: Replace HTTP links with HTTPS ones
  kbuild: trace functions in subdirectories of lib/
  kbuild: introduce ccflags-remove-y and asflags-remove-y
  kbuild: do not export LDFLAGS_vmlinux
  kbuild: always create directories of targets
  powerpc/boot: add DTB to 'targets'
  kbuild: buildtar: add dtbs support
  kbuild: remove cc-option test of -ffreestanding
  kbuild: remove cc-option test of -fno-stack-protector
  Revert "kbuild: Create directory for target DTB"
  kbuild: run the checker after the compiler
2020-08-09 14:10:26 -07:00
Masahiro Yamada
132305b3b4 kbuild: stop filtering out $(GCC_PLUGINS_CFLAGS) from cc-option base
Commit d26e941492 ("kbuild: no gcc-plugins during cc-option tests")
was neeeded because scripts/Makefile.gcc-plugins was too early.

This is unneeded by including scripts/Makefile.gcc-plugins last,
and being careful to not add cc-option tests after it.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-08-10 01:32:59 +09:00
Masahiro Yamada
e0fe0bbe57 kbuild: include scripts/Makefile.* only when relevant CONFIG is enabled
Currently, the top Makefile includes all of scripts/Makefile.<feature>
even if the associated CONFIG option is disabled.

Do not include unneeded Makefiles in order to slightly optimize the
parse stage.

Include $(include-y), and ignore $(include-).

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-08-10 01:32:59 +09:00
Masahiro Yamada
3ec8a5b33d kbuild: do not export LDFLAGS_vmlinux
When you clean the build tree for ARCH=arm, you may see the following
error message from 'nm' command:

$ make -j24 ARCH=arm clean
  CLEAN   arch/arm/crypto
  CLEAN   arch/arm/kernel
  CLEAN   arch/arm/mach-at91
  CLEAN   arch/arm/mach-omap2
  CLEAN   arch/arm/vdso
  CLEAN   certs
  CLEAN   lib
  CLEAN   usr
  CLEAN   net/wireless
  CLEAN   drivers/firmware/efi/libstub
nm: 'arch/arm/boot/compressed/../../../../vmlinux': No such file
/bin/sh: 1: arithmetic expression: expecting primary: " "
  CLEAN   arch/arm/boot/compressed
  CLEAN   drivers/scsi
  CLEAN   drivers/tty/vt
  CLEAN   arch/arm/boot
  CLEAN   vmlinux.symvers modules.builtin modules.builtin.modinfo

Even if you rerun the same command, the error message will not be
shown despite vmlinux is already gone.

To reproduce it, the parallel option -j is needed. Single thread
cleaning always executes 'archclean', 'vmlinuxclean' in this order,
so vmlinux still exists when arch/arm/boot/compressed/ is cleaned.

Looking at arch/arm/boot/compressed/Makefile does not help understand
the reason of the error message. Both KBSS_SZ and LDFLAGS_vmlinux are
assigned with '=' operator, hence, they are not expanded unless used.
Obviously, 'make clean' does not use them.

In fact, the root cause exists in the top Makefile:

  export LDFLAGS_vmlinux

Since LDFLAGS_vmlinux is an exported variable, LDFLAGS_vmlinux in
arch/arm/boot/compressed/Makefile is expanded when scripts/Makefile.clean
has a command to execute. This is why the error message shows up only
when there exist build artifacts in arch/arm/boot/compressed/.

Adding 'unexport LDFLAGS_vmlinux' to arch/arm/boot/compressed/Makefile
will fix it as far as ARCH=arm is concerned, but I think the proper fix
is to get rid of 'export LDFLAGS_vmlinux' from the top Makefile.

LDFLAGS_vmlinux in the top Makefile contains linker flags for the top
vmlinux. LDFLAGS_vmlinux in arch/arm/boot/compressed/Makefile is for
arch/arm/boot/compressed/vmlinux. They just happen to have the same
variable name, but are used for different purposes. Stop shadowing
LDFLAGS_vmlinux.

This commit passes LDFLAGS_vmlinux to scripts/link-vmlinux.sh via a
command line parameter instead of via an environment variable. LD and
KBUILD_LDFLAGS are exported, but I did the same for consistency. Anyway,
they must be included in cmd_link-vmlinux to allow if_changed to detect
the changes in LD or KBUILD_LDFLAGS.

The following Makefiles are not affected:

  arch/arm/boot/compressed/Makefile
  arch/h8300/boot/compressed/Makefile
  arch/nios2/boot/compressed/Makefile
  arch/parisc/boot/compressed/Makefile
  arch/s390/boot/compressed/Makefile
  arch/sh/boot/compressed/Makefile
  arch/sh/boot/romimage/Makefile
  arch/x86/boot/compressed/Makefile

They use ':=' or '=' to clear the LDFLAGS_vmlinux inherited from the
top Makefile.

We need to take a closer look at the impact to unicore32 and xtensa.

arch/unicore32/boot/compressed/Makefile only uses '+=' operator for
LDFLAGS_vmlinux. So, the decompressor previously inherited the linker
flags from the top Makefile.

However, commit 70fac51fea ("unicore32 additional architecture files:
boot process") was merged before commit 1f2bfbd00e ("kbuild: link of
vmlinux moved to a script"). So, I rather consider this is a bug fix of
1f2bfbd00e.

arch/xtensa/boot/boot-elf/Makefile is also affected, but this is also
considered a fix for the same reason. It did not inherit LDFLAGS_vmlinux
when commit 4bedea9454 ("[PATCH] xtensa: Architecture support for
Tensilica Xtensa Part 2") was merged. I deleted $(LDFLAGS_vmlinux),
which is now empty.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
2020-08-10 01:32:58 +09:00
Linus Torvalds
47ec5303d7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller:

 1) Support 6Ghz band in ath11k driver, from Rajkumar Manoharan.

 2) Support UDP segmentation in code TSO code, from Eric Dumazet.

 3) Allow flashing different flash images in cxgb4 driver, from Vishal
    Kulkarni.

 4) Add drop frames counter and flow status to tc flower offloading,
    from Po Liu.

 5) Support n-tuple filters in cxgb4, from Vishal Kulkarni.

 6) Various new indirect call avoidance, from Eric Dumazet and Brian
    Vazquez.

 7) Fix BPF verifier failures on 32-bit pointer arithmetic, from
    Yonghong Song.

 8) Support querying and setting hardware address of a port function via
    devlink, use this in mlx5, from Parav Pandit.

 9) Support hw ipsec offload on bonding slaves, from Jarod Wilson.

10) Switch qca8k driver over to phylink, from Jonathan McDowell.

11) In bpftool, show list of processes holding BPF FD references to
    maps, programs, links, and btf objects. From Andrii Nakryiko.

12) Several conversions over to generic power management, from Vaibhav
    Gupta.

13) Add support for SO_KEEPALIVE et al. to bpf_setsockopt(), from Dmitry
    Yakunin.

14) Various https url conversions, from Alexander A. Klimov.

15) Timestamping and PHC support for mscc PHY driver, from Antoine
    Tenart.

16) Support bpf iterating over tcp and udp sockets, from Yonghong Song.

17) Support 5GBASE-T i40e NICs, from Aleksandr Loktionov.

18) Add kTLS RX HW offload support to mlx5e, from Tariq Toukan.

19) Fix the ->ndo_start_xmit() return type to be netdev_tx_t in several
    drivers. From Luc Van Oostenryck.

20) XDP support for xen-netfront, from Denis Kirjanov.

21) Support receive buffer autotuning in MPTCP, from Florian Westphal.

22) Support EF100 chip in sfc driver, from Edward Cree.

23) Add XDP support to mvpp2 driver, from Matteo Croce.

24) Support MPTCP in sock_diag, from Paolo Abeni.

25) Commonize UDP tunnel offloading code by creating udp_tunnel_nic
    infrastructure, from Jakub Kicinski.

26) Several pci_ --> dma_ API conversions, from Christophe JAILLET.

27) Add FLOW_ACTION_POLICE support to mlxsw, from Ido Schimmel.

28) Add SK_LOOKUP bpf program type, from Jakub Sitnicki.

29) Refactor a lot of networking socket option handling code in order to
    avoid set_fs() calls, from Christoph Hellwig.

30) Add rfc4884 support to icmp code, from Willem de Bruijn.

31) Support TBF offload in dpaa2-eth driver, from Ioana Ciornei.

32) Support XDP_REDIRECT in qede driver, from Alexander Lobakin.

33) Support PCI relaxed ordering in mlx5 driver, from Aya Levin.

34) Support TCP syncookies in MPTCP, from Flowian Westphal.

35) Fix several tricky cases of PMTU handling wrt. briding, from Stefano
    Brivio.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2056 commits)
  net: thunderx: initialize VF's mailbox mutex before first usage
  usb: hso: remove bogus check for EINPROGRESS
  usb: hso: no complaint about kmalloc failure
  hso: fix bailout in error case of probe
  ip_tunnel_core: Fix build for archs without _HAVE_ARCH_IPV6_CSUM
  selftests/net: relax cpu affinity requirement in msg_zerocopy test
  mptcp: be careful on subflow creation
  selftests: rtnetlink: make kci_test_encap() return sub-test result
  selftests: rtnetlink: correct the final return value for the test
  net: dsa: sja1105: use detected device id instead of DT one on mismatch
  tipc: set ub->ifindex for local ipv6 address
  ipv6: add ipv6_dev_find()
  net: openvswitch: silence suspicious RCU usage warning
  Revert "vxlan: fix tos value before xmit"
  ptp: only allow phase values lower than 1 period
  farsync: switch from 'pci_' to 'dma_' API
  wan: wanxl: switch from 'pci_' to 'dma_' API
  hv_netvsc: do not use VF device if link is down
  dpaa2-eth: Fix passing zero to 'PTR_ERR' warning
  net: macb: Properly handle phylink on at91sam9x
  ...
2020-08-05 20:13:21 -07:00
Linus Torvalds
5b5d3be5d6 Automatic variable initialization updates for v5.9-rc1
- Introduce CONFIG_INIT_STACK_ALL_ZERO (Alexander Potapenko)
 -----BEGIN PGP SIGNATURE-----
 
 iQJKBAABCgA0FiEEpcP2jyKd1g9yPm4TiXL039xtwCYFAl8oXX4WHGtlZXNjb29r
 QGNocm9taXVtLm9yZwAKCRCJcvTf3G3AJt/FD/wJISl6Va3UvJrwGWcjLqb3iQh/
 38Nq7LV9ysUStpi5ibxhiB95uawFtAUsBLKyBKLtOERUz5RXiHrR9MI4UWNPBgNc
 7/H5ZAkkD21LpzC76FH+a4SWQp1kQTiyu/iONn03LE8p4vSwSVZzoGqA1r4fpzGY
 Np++2Ym/bzWV7R0Xdq/LI5oH9109dm75PhcCqCZPAtlIq+USXpyNAozimgREplVl
 /clYmj7oruoRYiF5uheOlbpCEXYlybwVHfDKE2Uh5IcXcpm3OYZU9HEK5ot5oudJ
 Z7bIcMeS2mMtSH/hhyjFbi0cZBVtJFc9exHRmuiDiYzNkWzaT2/5xAMUzw65q7Yk
 BTpr5AU+nkVQwuAmkN3AyBLrqQYyhWL0+xnWRmbbjt2yoqCx5x3AyxaBgHDV4vgF
 sTNhczFQdGqhlmvbxOw93PARV+lU9pozcc6b8TpXVdsE+bFFN5mBuRljIOTCRvke
 yxFsLF9olfNB3CXTHXAWLC/RuqdH/Vk7zC0vS34tlmvWgVC07P9QXyWciqcldAgL
 BsFXsRt6bRvOukyunhRfQkLVRxsOCLhQuYC33cRX9xY9vwCkM5v6TQH5WRcfxK7Q
 swujqqvozYZ/njblBTeagg8sGg0OiqxpCvJZD6qA6s1mO3lG58CDqqwxd4DemIDF
 /BxVarzUtmvBuiMBSQ==
 =c2Rf
 -----END PGP SIGNATURE-----

Merge tag 'var-init-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull automatic variable initialization updates from Kees Cook:
 "This adds the "zero" init option from Clang, which is being used
  widely in production builds of Android and Chrome OS (though it also
  keeps the "pattern" init, which is better for debug builds).

   - Introduce CONFIG_INIT_STACK_ALL_ZERO (Alexander Potapenko)"

* tag 'var-init-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  security: allow using Clang's zero initialization for stack variables
2020-08-04 13:38:35 -07:00
Linus Torvalds
c0dfadfed8 The main change in this cycle was to add support for ZSTD-compressed
kernel and initrd images.
 
 ZSTD has a very fast decompressor, yet it compresses better than gzip.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAl8oNX0RHG1pbmdvQGtl
 cm5lbC5vcmcACgkQEnMQ0APhK1jdcg/9GaPGjmNgMqi3tbfzU3z11OrbraRBgMj5
 jHIZ89DuzwsqU+jbwGHGiF45ge85iPK6i2ovR3ePzL0LAlLYT3gqzPcl3kkog4E9
 0E0JAddx974uW4toc8cGFEHNf4vXtvvi45FL2yvDoap9xLEcpJsQRdu9upPB4U3s
 +qotO6wJitM74g4l2WdbStzCAcL4ZXFA/ix19nUyLh4QlFBDqUHwufIhW1G0ciL4
 txMXJ23L7e+b6FUvGyK3vFhba1isPdz5xQdQTy2DCK20rQhGu1IBsqzymEibbgIp
 /j4yHfUKSpxdblFcpZfknI1VM1mbt/WN5dKDKm9UnYBhA/R/2PN0klfrAQAT4SOS
 sP3bxXqTRXBjmop0NjOLCdjGCySYnPLFPlB6REIrMcvs6LYUSTqMZEusj7McwD7h
 IqS4zGEMa5A+c6Q4160Qz+zrXIyh/n/bTR/6uOKUktkUQaJ+079P64NK9RtCYZTk
 dkIHJChjmWZGxxXHEbo+4e7bM8gAMHDmX2pdWE5u72oYJRqBv7PVyl+SHBk+onxM
 crtKvqOp8Q8coirlfjx5UynZeZmH1VuIFjpvnwlAtqxZGvuTWZ0ojq3E3Y/XwHQj
 bVejr9AQ1gS9ZBTKwwd5cf7mnOuiXrHrBP3E7buoRw8bWtL+yqHyybqccZnSOUVN
 lGFshs+7J5o=
 =bARW
 -----END PGP SIGNATURE-----

Merge tag 'x86-boot-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 boot updates from Ingo Molnar:
 "The main change in this cycle was to add support for ZSTD-compressed
  kernel and initrd images.

  ZSTD has a very fast decompressor, yet it compresses better than gzip"

* tag 'x86-boot-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Documentation: dontdiff: Add zstd compressed files
  .gitignore: Add ZSTD-compressed files
  x86: Add support for ZSTD compressed kernel
  x86: Bump ZO_z_extra_bytes margin for zstd
  usr: Add support for zstd compressed initramfs
  init: Add support for zstd compressed kernel
  lib: Add zstd support to decompress
  lib: Prepare zstd for preboot environment, improve performance
2020-08-03 16:03:23 -07:00
Linus Torvalds
bcf876870b Linux 5.8 2020-08-02 14:21:45 -07:00
David S. Miller
bd0b33b248 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Resolved kernel/bpf/btf.c using instructions from merge commit
69138b34a7

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-02 01:02:12 -07:00
Nick Terrell
48f7ddf785 init: Add support for zstd compressed kernel
- Add the zstd and zstd22 cmds to scripts/Makefile.lib

- Add the HAVE_KERNEL_ZSTD and KERNEL_ZSTD options

Architecture specific support is still needed for decompression.

Signed-off-by: Nick Terrell <terrelln@fb.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200730190841.2071656-4-nickrterrell@gmail.com
2020-07-31 11:49:08 +02:00
Linus Torvalds
92ed301919 Linux 5.8-rc7 2020-07-26 14:14:06 -07:00
Linus Torvalds
1c8594b842 Kbuild fixes for v5.8 (3rd)
- do not use non-portable strsep() in a host program
 
  - fix single target builds for external modules
 
  - change Clang's --prefix option to make it work for the latest Clang
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCgAzFiEEbmPs18K1szRHjPqEPYsBB53g2wYFAl8d53AVHG1hc2FoaXJv
 eUBrZXJuZWwub3JnAAoJED2LAQed4NsGRdgQAJZLfQfQuKOpvtV7OBmVffbI8rdx
 anZKWJ/ILtrlc6UkAP5eHlMw6x/uP+UjaiOSDbfHiiP4OfuEHjlfUvS36+rWCKtb
 g0F3Pf1EqABYrNScL8/n0K8GS++REf6X8DUqZ7MYtJFftPVsbkaXuxIFM9Et1U6d
 vrfvxH8z4S4/LzgANcrYd2sR0eLZNnoLpQb6qBWLLIdNXtF4xNQ17y0B4Ihpr/o3
 PnQu9ttJ8Xoh1kCMfkQkQKh3oL6rT7Tay7KB5AfABb0RHX5eI/x7vSThAxtgTzNA
 dOUxKeBFpPInw3XG8rTjRnr0msRGhFbDxC2zygiAv5Y+nz7D/ct9m7tAtCK1Zurn
 lLTkkXAcchbdk3z57wzEiiRS3ylE/b+Jn38BIQIbefwPYJpuIkFCfcvbmo5Z2rXs
 d/0x1co/PYcSCvlZJlLp8VpeM9yeZ0xXlmERJbPjFXEyh7XQw9NwShzvTPhaNjV8
 Ax4ZZ+U9m9/IJsO103HOTdFlFo3gmhgR8uVCsZ0+VT1VZtZ5PN5olJKcgOv0YrW3
 4/nqK7NsNJLMZEPImyam7UMUIspi8V8x6ujwgglBPftRIaYpHpG6sQ75deyqGVMh
 MSxiw/fysexABBUEC3QEh65qvLEcwzc8YN59TfCaPLJiN/B+2/nayqns8ozfSVzl
 PAYnj3FFWjZ9ij/B
 =zebF
 -----END PGP SIGNATURE-----

Merge tag 'kbuild-fixes-v5.8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild into master

Pull Kbuild fixes from Masahiro Yamada:

 - do not use non-portable strsep() in a host program

 - fix single target builds for external modules

 - change Clang's --prefix option to make it work for the latest Clang

* tag 'kbuild-fixes-v5.8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  Makefile: Fix GCC_TOOLCHAIN_DIR prefix for Clang cross compilation
  kbuild: fix single target builds for external modules
  modpost: remove use of non-standard strsep() in HOSTCC code
2020-07-26 13:46:57 -07:00
David S. Miller
a57066b1a0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
The UDP reuseport conflict was a little bit tricky.

The net-next code, via bpf-next, extracted the reuseport handling
into a helper so that the BPF sk lookup code could invoke it.

At the same time, the logic for reuseport handling of unconnected
sockets changed via commit efc6b6f6c3
which changed the logic to carry on the reuseport result into the
rest of the lookup loop if we do not return immediately.

This requires moving the reuseport_has_conns() logic into the callers.

While we are here, get rid of inline directives as they do not belong
in foo.c files.

The other changes were cases of more straightforward overlapping
modifications.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-25 17:49:04 -07:00
Fangrui Song
ca9b31f6bb Makefile: Fix GCC_TOOLCHAIN_DIR prefix for Clang cross compilation
When CROSS_COMPILE is set (e.g. aarch64-linux-gnu-), if
$(CROSS_COMPILE)elfedit is found at /usr/bin/aarch64-linux-gnu-elfedit,
GCC_TOOLCHAIN_DIR will be set to /usr/bin/.  --prefix= will be set to
/usr/bin/ and Clang as of 11 will search for both
$(prefix)aarch64-linux-gnu-$needle and $(prefix)$needle.

GCC searchs for $(prefix)aarch64-linux-gnu/$version/$needle,
$(prefix)aarch64-linux-gnu/$needle and $(prefix)$needle. In practice,
$(prefix)aarch64-linux-gnu/$needle rarely contains executables.

To better model how GCC's -B/--prefix takes in effect in practice, newer
Clang (since
3452a0d8c1)
only searches for $(prefix)$needle. Currently it will find /usr/bin/as
instead of /usr/bin/aarch64-linux-gnu-as.

Set --prefix= to $(GCC_TOOLCHAIN_DIR)$(notdir $(CROSS_COMPILE))
(/usr/bin/aarch64-linux-gnu-) so that newer Clang can find the
appropriate cross compiling GNU as (when -no-integrated-as is in
effect).

Cc: stable@vger.kernel.org
Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Fangrui Song <maskray@google.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/1099
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-07-23 11:29:07 +09:00
Linus Torvalds
ba47d845d7 Linux 5.8-rc6 2020-07-19 15:41:18 -07:00
David S. Miller
07dd1b7e68 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2020-07-13

The following pull-request contains BPF updates for your *net-next* tree.

We've added 36 non-merge commits during the last 7 day(s) which contain
a total of 62 files changed, 2242 insertions(+), 468 deletions(-).

The main changes are:

1) Avoid trace_printk warning banner by switching bpf_trace_printk to use
   its own tracing event, from Alan.

2) Better libbpf support on older kernels, from Andrii.

3) Additional AF_XDP stats, from Ciara.

4) build time resolution of BTF IDs, from Jiri.

5) BPF_CGROUP_INET_SOCK_RELEASE hook, from Stanislav.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-13 18:04:05 -07:00
Jiri Olsa
c9a0f3b85e bpf: Resolve BTF IDs in vmlinux image
Using BTF_ID_LIST macro to define lists for several helpers
using BTF arguments.

And running resolve_btfids on vmlinux elf object during linking,
so the .BTF_ids section gets the IDs resolved.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200711215329.41165-5-jolsa@kernel.org
2020-07-13 10:42:02 -07:00
Jiri Olsa
33a57ce0a5 bpf: Compile resolve_btfids tool at kernel compilation start
The resolve_btfids tool will be used during the vmlinux linking,
so it's necessary it's ready for it.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200711215329.41165-3-jolsa@kernel.org
2020-07-13 10:42:02 -07:00
Linus Torvalds
11ba468877 Linux 5.8-rc5 2020-07-12 16:34:50 -07:00
Masahiro Yamada
20b1be5952 kbuild: fix single target builds for external modules
Commit f566e1fbad ("kbuild: make multiple directory targets work")
broke single target builds for external modules. Fix this.

Fixes: f566e1fbad ("kbuild: make multiple directory targets work")
Reported-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Bjørn Mork <bjorn@mork.no>
2020-07-11 23:56:21 +09:00
Masahiro Yamada
893ab00439 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 <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2020-07-07 11:13:10 +09:00
Linus Torvalds
dcb7fd82c7 Linux 5.8-rc4 2020-07-05 16:20:22 -07:00
Linus Torvalds
4bc927367d Kbuild fixes for v5.8 (2nd)
- fix various bugs in xconfig
 
  - fix some issues in cross-compilation using Clang
 
  - fix documentation
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCgAzFiEEbmPs18K1szRHjPqEPYsBB53g2wYFAl8B7PAVHG1hc2FoaXJv
 eUBrZXJuZWwub3JnAAoJED2LAQed4NsGKnwP/2lAwlPJYRjBv0cLZ8HI1F8xbVFl
 P+/JPkF0me/4mXU0ZJzP+zeLq9rfjL9298FwkVtPoTybPCSsONVEuoIMZ5gCXYxc
 IJ6o7pwmSF7T7VNtI6lx+l4BKmULYnPpTnZsqutKKLjAO+o2SiHju3ZSgfWUXVuc
 NyQIFSBQzoI1KkbNHpuAryWc0WXm6Gfeg3//Sqqk/pPmXkNcQAIzM274HvrSnCvq
 /RLUd0SDTXP7XlbleZQhms1FJp3IXkSXAGdA0HsF8sH8oCz+4wWcXk72k4j9INXi
 aPACxZvO/hM4N9LJliL4eJjjHfmbnDppczr+Kb5KYCb9dEV9vVkbYWyz98YA+/Y/
 1EgynxLxHrU534M7tAhRAb0k/xVGodhRj0KEMPGRgzeWGtXaxKSe0Z5NBqs0nj5Z
 dMtJuzEMG1ey56jhRj2408IUUmOmHEh+IDsM8HQ/tcjrI5fpKP505RT6gvLBWX6M
 IPPYo2cC9wHfyEC1dPjJ+aaOeqnSJ9+7ui7iv5vJQ1M6PyOkHeXaU1jCeOGg5qLe
 zfjn2U11uK3BLgedzahB/lEBXfblDlFuG0b7XyXnyyhkICt1CT7aPvznrGxSUlEw
 EuZLrIMHqRwMyrs7PTo41m2hf3hqh+juhPuxiEngi5NqH/GKBnvLJQDGFkbupqim
 ZFGZnMVeZR7Prulc
 =0BKC
 -----END PGP SIGNATURE-----

Merge tag 'kbuild-fixes-v5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes frin Masahiro Yamada:

 - fix various bugs in xconfig

 - fix some issues in cross-compilation using Clang

 - fix documentation

* tag 'kbuild-fixes-v5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  .gitignore: Do not track `defconfig` from `make savedefconfig`
  kbuild: make Clang build userprogs for target architecture
  kbuild: fix CONFIG_CC_CAN_LINK(_STATIC) for cross-compilation with Clang
  kconfig: qconf: parse newer types at debug info
  kconfig: qconf: navigate menus on hyperlinks
  kconfig: qconf: don't show goback button on splitMode
  kconfig: qconf: simplify the goBack() logic
  kconfig: qconf: re-implement setSelected()
  kconfig: qconf: make debug links work again
  kconfig: qconf: make search fully work again on split mode
  kconfig: qconf: cleanup includes
  docs: kbuild: fix ReST formatting
  gcc-plugins: fix gcc-plugins directory path in documentation
2020-07-05 12:14:24 -07:00
Masahiro Yamada
7f58b487e9 kbuild: make Clang build userprogs for target architecture
Programs added 'userprogs' should be compiled for the target
architecture i.e. the same architecture as the kernel.

GCC does this correctly since the target architecture is implied
by the toolchain prefix.

Clang builds userspace programs always for the host architecture
because the target triple is currently missing.

Fix this.

Fixes: 7f3a59db27 ("kbuild: add infrastructure to build userspace programs")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
2020-07-02 00:58:00 +09:00
Linus Torvalds
9ebcfadb06 Linux 5.8-rc3 2020-06-28 15:00:24 -07:00
Linus Torvalds
48778464bb Linux 5.8-rc2 2020-06-21 15:45:29 -07:00
Masahiro Yamada
2c6d9636ad Revert "Makefile: install modules.builtin even if CONFIG_MODULES=n"
This reverts commit e0b250b57d,
which broke build systems that need to install files to a certain
path, but do not set INSTALL_MOD_PATH when invoking 'make install'.

  $ make INSTALL_PATH=/tmp/destdir install
  mkdir: cannot create directory ‘/lib/modules/5.8.0-rc1+/’: Permission denied
  Makefile:1342: recipe for target '_builtin_inst_' failed
  make: *** [_builtin_inst_] Error 1

While modules.builtin is useful also for CONFIG_MODULES=n, this change
in the behavior is quite unexpected. Maybe "make modules_install"
can install modules.builtin irrespective of CONFIG_MODULES as Jonas
originally suggested.

Anyway, that commit should be reverted ASAP.

Reported-by: Douglas Anderson <dianders@chromium.org>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Cc: Jonas Karlman <jonas@kwiboo.se>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
2020-06-22 00:19:14 +09:00
glider@google.com
f0fe00d497 security: allow using Clang's zero initialization for stack variables
In addition to -ftrivial-auto-var-init=pattern (used by
CONFIG_INIT_STACK_ALL now) Clang also supports zero initialization for
locals enabled by -ftrivial-auto-var-init=zero. The future of this flag
is still being debated (see https://bugs.llvm.org/show_bug.cgi?id=45497).
Right now it is guarded by another flag,
-enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang,
which means it may not be supported by future Clang releases. Another
possible resolution is that -ftrivial-auto-var-init=zero will persist
(as certain users have already started depending on it), but the name
of the guard flag will change.

In the meantime, zero initialization has proven itself as a good
production mitigation measure against uninitialized locals. Unlike pattern
initialization, which has a higher chance of triggering existing bugs,
zero initialization provides safe defaults for strings, pointers, indexes,
and sizes. On the other hand, pattern initialization remains safer for
return values. Chrome OS and Android are moving to using zero
initialization for production builds.

Performance-wise, the difference between pattern and zero initialization
is usually negligible, although the generated code for zero
initialization is more compact.

This patch renames CONFIG_INIT_STACK_ALL to CONFIG_INIT_STACK_ALL_PATTERN
and introduces another config option, CONFIG_INIT_STACK_ALL_ZERO, that
enables zero initialization for locals if the corresponding flags are
supported by Clang.

Cc: Kees Cook <keescook@chromium.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Alexander Potapenko <glider@google.com>
Link: https://lore.kernel.org/r/20200616083435.223038-1-glider@google.com
Reviewed-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
2020-06-16 02:06:23 -07:00
Arvind Sankar
7b16994437 Makefile: Improve compressed debug info support detection
Commit
  10e68b02c8 ("Makefile: support compressed debug info")
added support for compressed debug sections.

Support is detected by checking
- does the compiler support -gz=zlib
- does the assembler support --compressed-debug-sections=zlib
- does the linker support --compressed-debug-sections=zlib

However, the gcc driver's support for this option is somewhat
convoluted. The driver's builtin specs are set based on the version of
binutils that it was configured with. It reports an error if the
configure-time linker/assembler (i.e., not necessarily the actual
assembler that will be run) do not support the option, but only if the
assembler (or linker) is actually invoked when -gz=zlib is passed.

The cc-option check in scripts/Kconfig.include does not invoke the
assembler, so the gcc driver reports success even if it does not support
the option being passed to the assembler.

Because the as-option check passes the option directly to the assembler
via -Wa,--compressed-debug-sections=zlib, the gcc driver does not see
this option and will never report an error.

Combined with an installed version of binutils that is more recent than
the one the compiler was built with, it is possible for all three tests
to succeed, yet an actual compilation with -gz=zlib to fail.

Moreover, it is unnecessary to explicitly pass
--compressed-debug-sections=zlib to the assembler via -Wa, since the
driver will do that automatically when it supports -gz=zlib.

Convert the as-option to just -gz=zlib, simplifying it as well as
performing a better test of the gcc driver's capabilities.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-15 10:26:42 +09:00
Linus Torvalds
b3a9e3b962 Linux 5.8-rc1 2020-06-14 12:45:04 -07:00
Linus Torvalds
6adc19fd13 Kbuild updates for v5.8 (2nd)
- fix build rules in binderfs sample
 
  - fix build errors when Kbuild recurses to the top Makefile
 
  - covert '---help---' in Kconfig to 'help'
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCgAzFiEEbmPs18K1szRHjPqEPYsBB53g2wYFAl7lBuYVHG1hc2FoaXJv
 eUBrZXJuZWwub3JnAAoJED2LAQed4NsGHvIP/3iErjPshpg/phwH8NTCS4SFkiti
 BZRM+2lupSn7Qs53BTpVzIkXoHBJQZlJxlQ5HY8ScO+fiz28rKZr+b40us+je1Q+
 SkvSPfwZzxjEg7lAZutznG4KgItJLWJKmDyh9T8Y8TAuG4f8WO0hKnXoAp3YorS2
 zppEIxso8O5spZPjp+fF/fPbxPjIsabGK7Jp2LpSVFR5pVDHI/ycTlKQS+MFpMEx
 6JIpdFRw7TkvKew1dr5uAWT5btWHatEqjSR3JeyVHv3EICTGQwHmcHK67cJzGInK
 T51+DT7/CpKtmRgGMiTEu/INfMzzoQAKl6Fcu+vMaShTN97Hk9DpdtQyvA6P/h3L
 8GA4UBct05J7fjjIB7iUD+GYQ0EZbaFujzRXLYk+dQqEJRbhcCwvdzggGp0WvGRs
 1f8/AIpgnQv8JSL/bOMgGMS5uL2dSLsgbzTdr6RzWf1jlYdI1i4u7AZ/nBrwWP+Z
 iOBkKsVceEoJrTbaynl3eoYqFLtWyDau+//oBc2gUvmhn8ioM5dfqBRiJjxJnPG9
 /giRj6xRIqMMEw8Gg8PCG7WebfWxWyaIQwlWBbPok7DwISURK5mvOyakZL+Q25/y
 6MBr2H8NEJsf35q0GTINpfZnot7NX4JXrrndJH8NIRC7HEhwd29S041xlQJdP0rs
 E76xsOr3hrAmBu4P
 =1NIT
 -----END PGP SIGNATURE-----

Merge tag 'kbuild-v5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull more Kbuild updates from Masahiro Yamada:

 - fix build rules in binderfs sample

 - fix build errors when Kbuild recurses to the top Makefile

 - covert '---help---' in Kconfig to 'help'

* tag 'kbuild-v5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  treewide: replace '---help---' in Kconfig files with 'help'
  kbuild: fix broken builds because of GZIP,BZIP2,LZOP variables
  samples: binderfs: really compile this sample and fix build issues
2020-06-13 13:29:16 -07:00
Thomas Gleixner
37d1a04b13 Rebase locking/kcsan to locking/urgent
Merge the state of the locking kcsan branch before the read/write_once()
and the atomics modifications got merged.

Squash the fallout of the rebase on top of the read/write once and atomic
fallback work into the merge. The history of the original branch is
preserved in tag locking-kcsan-2020-06-02.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2020-06-11 20:02:46 +02:00
Denis Efremov
e4a42c82e9 kbuild: fix broken builds because of GZIP,BZIP2,LZOP variables
Redefine GZIP, BZIP2, LZOP variables as KGZIP, KBZIP2, KLZOP resp.
GZIP, BZIP2, LZOP env variables are reserved by the tools. The original
attempt to redefine them internally doesn't work in makefiles/scripts
intercall scenarios, e.g., "make GZIP=gzip bindeb-pkg" and results in
broken builds. There can be other broken build commands because of this,
so the universal solution is to use non-reserved env variables for the
compression tools.

Fixes: 8dfb61dcba ("kbuild: add variables for compression tools")
Signed-off-by: Denis Efremov <efremov@linux.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-11 20:14:41 +09:00
Linus Torvalds
cff11abeca Kbuild updates for v5.8
- fix warnings in 'make clean' for ARCH=um, hexagon, h8300, unicore32
 
  - ensure to rebuild all objects when the compiler is upgraded
 
  - exclude system headers from dependency tracking and fixdep processing
 
  - fix potential bit-size mismatch between the kernel and BPF user-mode
    helper
 
  - add the new syntax 'userprogs' to build user-space programs for the
    target architecture (the same arch as the kernel)
 
  - compile user-space sample code under samples/ for the target arch
    instead of the host arch
 
  - make headers_install fail if a CONFIG option is leaked to user-space
 
  - sanitize the output format of scripts/checkstack.pl
 
  - handle ARM 'push' instruction in scripts/checkstack.pl
 
  - error out before modpost if a module name conflict is found
 
  - error out when multiple directories are passed to M= because this
    feature is broken for a long time
 
  - add CONFIG_DEBUG_INFO_COMPRESSED to support compressed debug info
 
  - a lot of cleanups of modpost
 
  - dump vmlinux symbols out into vmlinux.symvers, and reuse it in the
    second pass of modpost
 
  - do not run the second pass of modpost if nothing in modules is updated
 
  - install modules.builtin(.modinfo) by 'make install' as well as by
    'make modules_install' because it is useful even when CONFIG_MODULES=n
 
  - add new command line variables, GZIP, BZIP2, LZOP, LZMA, LZ4, and XZ
    to allow users to use alternatives such as pigz, pbzip2, etc.
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCgAzFiEEbmPs18K1szRHjPqEPYsBB53g2wYFAl7brm0VHG1hc2FoaXJv
 eUBrZXJuZWwub3JnAAoJED2LAQed4NsGjeEP/Rrf8H9cp/Tq+ALQCBycI3W5ZEHg
 n2EqprZkVP2MlOV0d+8b9t4PdZf6E5Wmfv26sMaBAhl6X1KQI/0NgPMnTINvy5jJ
 Q2SMhj9y8Gwr3XKFu9Hd/0U+Sax5rz+LmY84tdF95dXzPIUWjAEVnbmN+ofY6T++
 sNf2YGNFSR6iiqr3uCYA0hHZmpKlfhVgDPAdncWa5aadSsuQb79nZQWefGeVEsuD
 HrISpwnkhBc0qY1xyWry6agE92xWmkNkdjKq6A7peguZL02XySWLRWjyHoiiaPOB
 6U4urKs/NSXqPgxGxwZthhwERHryC3+g4s8wRBDKE6ISRWKBBA2ruHpgdF5h/utu
 re1ZP2qRcAt8NBFynr4MEb2AU0mYkv7iEgfLJ7NUCRlMOtqrn5RFwnS4r8ReyQp5
 1UM11RbPhYgYjM5g9hBHJ7nK944/kfvy1/4jF4I1+M5O7QL6f00pu3r2bBIa/65g
 DWrNOpIliKG27GgnRlxi7HgLfxs9etFcXTpHO0ymgnMmlz+7FQsdceR9qqybGU9o
 yBWw6zculMQjb3E+k0DTnE5kLWsycbua921wxM9ABSxRmJi7WciNF73RdLUIBoAY
 VUbwrP2aIpdL+2uyX6RqdTaWzEBpW8omszr46aQ96pX+RiqMrPvJRLaA/tr3ZH8g
 tdHenJPWdHSaOcO4
 =GKe5
 -----END PGP SIGNATURE-----

Merge tag 'kbuild-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - fix warnings in 'make clean' for ARCH=um, hexagon, h8300, unicore32

 - ensure to rebuild all objects when the compiler is upgraded

 - exclude system headers from dependency tracking and fixdep processing

 - fix potential bit-size mismatch between the kernel and BPF user-mode
   helper

 - add the new syntax 'userprogs' to build user-space programs for the
   target architecture (the same arch as the kernel)

 - compile user-space sample code under samples/ for the target arch
   instead of the host arch

 - make headers_install fail if a CONFIG option is leaked to user-space

 - sanitize the output format of scripts/checkstack.pl

 - handle ARM 'push' instruction in scripts/checkstack.pl

 - error out before modpost if a module name conflict is found

 - error out when multiple directories are passed to M= because this
   feature is broken for a long time

 - add CONFIG_DEBUG_INFO_COMPRESSED to support compressed debug info

 - a lot of cleanups of modpost

 - dump vmlinux symbols out into vmlinux.symvers, and reuse it in the
   second pass of modpost

 - do not run the second pass of modpost if nothing in modules is
   updated

 - install modules.builtin(.modinfo) by 'make install' as well as by
   'make modules_install' because it is useful even when
   CONFIG_MODULES=n

 - add new command line variables, GZIP, BZIP2, LZOP, LZMA, LZ4, and XZ
   to allow users to use alternatives such as pigz, pbzip2, etc.

* tag 'kbuild-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (96 commits)
  kbuild: add variables for compression tools
  Makefile: install modules.builtin even if CONFIG_MODULES=n
  mksysmap: Fix the mismatch of '.L' symbols in System.map
  kbuild: doc: rename LDFLAGS to KBUILD_LDFLAGS
  modpost: change elf_info->size to size_t
  modpost: remove is_vmlinux() helper
  modpost: strip .o from modname before calling new_module()
  modpost: set have_vmlinux in new_module()
  modpost: remove mod->skip struct member
  modpost: add mod->is_vmlinux struct member
  modpost: remove is_vmlinux() call in check_for_{gpl_usage,unused}()
  modpost: remove mod->is_dot_o struct member
  modpost: move -d option in scripts/Makefile.modpost
  modpost: remove -s option
  modpost: remove get_next_text() and make {grab,release_}file static
  modpost: use read_text_file() and get_line() for reading text files
  modpost: avoid false-positive file open error
  modpost: fix potential mmap'ed file overrun in get_src_version()
  modpost: add read_text_file() and get_line() helpers
  modpost: do not call get_modinfo() for vmlinux(.o)
  ...
2020-06-06 12:00:25 -07:00
Denis Efremov
8dfb61dcba kbuild: add variables for compression tools
Allow user to use alternative implementations of compression tools,
such as pigz, pbzip2, pxz. For example, multi-threaded tools to
speed up the build:
$ make GZIP=pigz BZIP2=pbzip2

Variables _GZIP, _BZIP2, _LZOP are used internally because original env
vars are reserved by the tools. The use of GZIP in gzip tool is obsolete
since 2015. However, alternative implementations (e.g., pigz) still rely
on it. BZIP2, BZIP, LZOP vars are not obsolescent.

The credit goes to @grsecurity.

As a sidenote, for multi-threaded lzma, xz compression one can use:
$ export XZ_OPT="--threads=0"

Signed-off-by: Denis Efremov <efremov@linux.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:42:01 +09:00
Jonas Zeiger
e0b250b57d Makefile: install modules.builtin even if CONFIG_MODULES=n
Many applications check for available kernel features via:

  - /proc/modules (loaded modules, present if CONFIG_MODULES=y)
  - $(MODLIB)/modules.builtin (builtin modules)

They fail to detect features if the kernel was built with CONFIG_MODULES=n
and modules.builtin isn't installed.

Therefore, add the target "_builtin_inst_" and make "install" and
"modules_install" depend on it.

Tests results:

  - make install: kernel image is copied as before, modules.builtin copied
  - make modules_install: (CONFIG_MODULES=n) nothing is copied, exit 1

Signed-off-by: Jonas Zeiger <jonas.zeiger@talpidae.net>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:41:49 +09:00
Masahiro Yamada
48a0f72797 modpost: show warning if any of symbol dump files is missing
If modpost fails to load a symbol dump file, it cannot check unresolved
symbols, hence module dependency will not be added. Nor CRCs can be added.

Currently, external module builds check only $(objtree)/Module.symvers,
but it should check files specified by KBUILD_EXTRA_SYMBOLS as well.

Move the warning message from the top Makefile to scripts/Makefile.modpost
and print the warning if any dump file is missing.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:12 +09:00
Masahiro Yamada
269a535ca9 modpost: generate vmlinux.symvers and reuse it for the second modpost
The full build runs modpost twice, first for vmlinux.o and second for
modules.

The first pass dumps all the vmlinux symbols into Module.symvers, but
the second pass parses vmlinux again instead of reusing the dump file,
presumably because it needs to avoid accumulating stale symbols.

Loading symbol info from a dump file is faster than parsing an ELF object.
Besides, modpost deals with various issues to parse vmlinux in the second
pass.

A solution is to make the first pass dumps symbols into a separate file,
vmlinux.symvers. The second pass reads it, and parses module .o files.
The merged symbol information is dumped into Module.symvers in the same
way as before.

This makes further modpost cleanups possible.

Also, it fixes the problem of 'make vmlinux', which previously overwrote
Module.symvers, throwing away module symbols.

I slightly touched scripts/link-vmlinux.sh so that vmlinux is re-linked
when you cross this commit. Otherwise, vmlinux.symvers would not be
generated.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:12 +09:00
Masahiro Yamada
b2c8855491 kbuild: update modules.order only when contained modules are updated
Make modules.order depend on $(obj-m), and use if_changed to build it.
This will avoid unneeded update of modules.order, which will be useful
to optimize the modpost stage.

Currently, the second pass of modpost is always invoked. By checking the
timestamp of modules.order, we can avoid the unneeded modpost.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-03 13:22:17 +09:00
Masahiro Yamada
f0d50ca045 kbuild: refactor KBUILD_VMLINUX_{OBJS,LIBS} calculation
Do not overwrite core-y or drivers-y. Remove libs-y1 and libs-y2.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-03 13:22:07 +09:00
Linus Torvalds
533b220f7b arm64 updates for 5.8
- Branch Target Identification (BTI)
 	* Support for ARMv8.5-BTI in both user- and kernel-space. This
 	  allows branch targets to limit the types of branch from which
 	  they can be called and additionally prevents branching to
 	  arbitrary code, although kernel support requires a very recent
 	  toolchain.
 
 	* Function annotation via SYM_FUNC_START() so that assembly
 	  functions are wrapped with the relevant "landing pad"
 	  instructions.
 
 	* BPF and vDSO updates to use the new instructions.
 
 	* Addition of a new HWCAP and exposure of BTI capability to
 	  userspace via ID register emulation, along with ELF loader
 	  support for the BTI feature in .note.gnu.property.
 
 	* Non-critical fixes to CFI unwind annotations in the sigreturn
 	  trampoline.
 
 - Shadow Call Stack (SCS)
 	* Support for Clang's Shadow Call Stack feature, which reserves
 	  platform register x18 to point at a separate stack for each
 	  task that holds only return addresses. This protects function
 	  return control flow from buffer overruns on the main stack.
 
 	* Save/restore of x18 across problematic boundaries (user-mode,
 	  hypervisor, EFI, suspend, etc).
 
 	* Core support for SCS, should other architectures want to use it
 	  too.
 
 	* SCS overflow checking on context-switch as part of the existing
 	  stack limit check if CONFIG_SCHED_STACK_END_CHECK=y.
 
 - CPU feature detection
 	* Removed numerous "SANITY CHECK" errors when running on a system
 	  with mismatched AArch32 support at EL1. This is primarily a
 	  concern for KVM, which disabled support for 32-bit guests on
 	  such a system.
 
 	* Addition of new ID registers and fields as the architecture has
 	  been extended.
 
 - Perf and PMU drivers
 	* Minor fixes and cleanups to system PMU drivers.
 
 - Hardware errata
 	* Unify KVM workarounds for VHE and nVHE configurations.
 
 	* Sort vendor errata entries in Kconfig.
 
 - Secure Monitor Call Calling Convention (SMCCC)
 	* Update to the latest specification from Arm (v1.2).
 
 	* Allow PSCI code to query the SMCCC version.
 
 - Software Delegated Exception Interface (SDEI)
 	* Unexport a bunch of unused symbols.
 
 	* Minor fixes to handling of firmware data.
 
 - Pointer authentication
 	* Add support for dumping the kernel PAC mask in vmcoreinfo so
 	  that the stack can be unwound by tools such as kdump.
 
 	* Simplification of key initialisation during CPU bringup.
 
 - BPF backend
 	* Improve immediate generation for logical and add/sub
 	  instructions.
 
 - vDSO
 	- Minor fixes to the linker flags for consistency with other
 	  architectures and support for LLVM's unwinder.
 
 	- Clean up logic to initialise and map the vDSO into userspace.
 
 - ACPI
 	- Work around for an ambiguity in the IORT specification relating
 	  to the "num_ids" field.
 
 	- Support _DMA method for all named components rather than only
 	  PCIe root complexes.
 
 	- Minor other IORT-related fixes.
 
 - Miscellaneous
 	* Initialise debug traps early for KGDB and fix KDB cacheflushing
 	  deadlock.
 
 	* Minor tweaks to early boot state (documentation update, set
 	  TEXT_OFFSET to 0x0, increase alignment of PE/COFF sections).
 
 	* Refactoring and cleanup
 -----BEGIN PGP SIGNATURE-----
 
 iQFEBAABCgAuFiEEPxTL6PPUbjXGY88ct6xw3ITBYzQFAl7U9csQHHdpbGxAa2Vy
 bmVsLm9yZwAKCRC3rHDchMFjNLBHCACs/YU4SM7Om5f+7QnxIKao5DBr2CnGGvdC
 yTfDghFDTLQVv3MufLlfno3yBe5G8sQpcZfcc+hewfcGoMzVZXu8s7LzH6VSn9T9
 jmT3KjDMrg0RjSHzyumJp2McyelTk0a4FiKArSIIKsJSXUyb1uPSgm7SvKVDwEwU
 JGDzL9IGilmq59GiXfDzGhTZgmC37QdwRoRxDuqtqWQe5CHoRXYexg87HwBKOQxx
 HgU9L7ehri4MRZfpyjaDrr6quJo3TVnAAKXNBh3mZAskVS9ZrfKpEH0kYWYuqybv
 znKyHRecl/rrGePV8RTMtrwnSdU26zMXE/omsVVauDfG9hqzqm+Q
 =w3qi
 -----END PGP SIGNATURE-----

Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Will Deacon:
 "A sizeable pile of arm64 updates for 5.8.

  Summary below, but the big two features are support for Branch Target
  Identification and Clang's Shadow Call stack. The latter is currently
  arm64-only, but the high-level parts are all in core code so it could
  easily be adopted by other architectures pending toolchain support

  Branch Target Identification (BTI):

   - Support for ARMv8.5-BTI in both user- and kernel-space. This allows
     branch targets to limit the types of branch from which they can be
     called and additionally prevents branching to arbitrary code,
     although kernel support requires a very recent toolchain.

   - Function annotation via SYM_FUNC_START() so that assembly functions
     are wrapped with the relevant "landing pad" instructions.

   - BPF and vDSO updates to use the new instructions.

   - Addition of a new HWCAP and exposure of BTI capability to userspace
     via ID register emulation, along with ELF loader support for the
     BTI feature in .note.gnu.property.

   - Non-critical fixes to CFI unwind annotations in the sigreturn
     trampoline.

  Shadow Call Stack (SCS):

   - Support for Clang's Shadow Call Stack feature, which reserves
     platform register x18 to point at a separate stack for each task
     that holds only return addresses. This protects function return
     control flow from buffer overruns on the main stack.

   - Save/restore of x18 across problematic boundaries (user-mode,
     hypervisor, EFI, suspend, etc).

   - Core support for SCS, should other architectures want to use it
     too.

   - SCS overflow checking on context-switch as part of the existing
     stack limit check if CONFIG_SCHED_STACK_END_CHECK=y.

  CPU feature detection:

   - Removed numerous "SANITY CHECK" errors when running on a system
     with mismatched AArch32 support at EL1. This is primarily a concern
     for KVM, which disabled support for 32-bit guests on such a system.

   - Addition of new ID registers and fields as the architecture has
     been extended.

  Perf and PMU drivers:

   - Minor fixes and cleanups to system PMU drivers.

  Hardware errata:

   - Unify KVM workarounds for VHE and nVHE configurations.

   - Sort vendor errata entries in Kconfig.

  Secure Monitor Call Calling Convention (SMCCC):

   - Update to the latest specification from Arm (v1.2).

   - Allow PSCI code to query the SMCCC version.

  Software Delegated Exception Interface (SDEI):

   - Unexport a bunch of unused symbols.

   - Minor fixes to handling of firmware data.

  Pointer authentication:

   - Add support for dumping the kernel PAC mask in vmcoreinfo so that
     the stack can be unwound by tools such as kdump.

   - Simplification of key initialisation during CPU bringup.

  BPF backend:

   - Improve immediate generation for logical and add/sub instructions.

  vDSO:

   - Minor fixes to the linker flags for consistency with other
     architectures and support for LLVM's unwinder.

   - Clean up logic to initialise and map the vDSO into userspace.

  ACPI:

   - Work around for an ambiguity in the IORT specification relating to
     the "num_ids" field.

   - Support _DMA method for all named components rather than only PCIe
     root complexes.

   - Minor other IORT-related fixes.

  Miscellaneous:

   - Initialise debug traps early for KGDB and fix KDB cacheflushing
     deadlock.

   - Minor tweaks to early boot state (documentation update, set
     TEXT_OFFSET to 0x0, increase alignment of PE/COFF sections).

   - Refactoring and cleanup"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (148 commits)
  KVM: arm64: Move __load_guest_stage2 to kvm_mmu.h
  KVM: arm64: Check advertised Stage-2 page size capability
  arm64/cpufeature: Add get_arm64_ftr_reg_nowarn()
  ACPI/IORT: Remove the unused __get_pci_rid()
  arm64/cpuinfo: Add ID_MMFR4_EL1 into the cpuinfo_arm64 context
  arm64/cpufeature: Add remaining feature bits in ID_AA64PFR1 register
  arm64/cpufeature: Add remaining feature bits in ID_AA64PFR0 register
  arm64/cpufeature: Add remaining feature bits in ID_AA64ISAR0 register
  arm64/cpufeature: Add remaining feature bits in ID_MMFR4 register
  arm64/cpufeature: Add remaining feature bits in ID_PFR0 register
  arm64/cpufeature: Introduce ID_MMFR5 CPU register
  arm64/cpufeature: Introduce ID_DFR1 CPU register
  arm64/cpufeature: Introduce ID_PFR2 CPU register
  arm64/cpufeature: Make doublelock a signed feature in ID_AA64DFR0
  arm64/cpufeature: Drop TraceFilt feature exposure from ID_DFR0 register
  arm64/cpufeature: Add explicit ftr_id_isar0[] for ID_ISAR0 register
  arm64: mm: Add asid_gen_match() helper
  firmware: smccc: Fix missing prototype warning for arm_smccc_version_init
  arm64: vdso: Fix CFI directives in sigreturn trampoline
  arm64: vdso: Don't prefix sigreturn trampoline with a BTI C instruction
  ...
2020-06-01 15:18:27 -07:00
Masahiro Yamada
95fb6317b3 kbuild: merge net-y and virt-y into drivers-y
This will slightly change the link order; drivers-y from arch Makefile
will be linked after virt/built-in.a, but I guess this is not a big
deal.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-01 21:50:48 +09:00
Masahiro Yamada
23febe375d kbuild: merge init-y into core-y
No arch Makefile specifies init-y.

Merge init-y into core-y. This does not change the link order.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-01 21:50:46 +09:00
Masahiro Yamada
fb2d99be89 kbuild: merge two 'ifdef CONFIG_TRIM_UNUSED_KSYMS' blocks
This hunk has two 'ifdef CONFIG_TRIM_UNUSED_KSYMS ... endif' blocks
with no other code interleaved. Merge them.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-01 21:50:44 +09:00
Masahiro Yamada
4b50c8c4ea kbuild: force to build vmlinux if CONFIG_MODVERSION=y
This code does not work as stated in the comment.

$(CONFIG_MODVERSIONS) is always empty because it is expanded before
include/config/auto.conf is included. Hence, 'make modules' with
CONFIG_MODVERSION=y cannot record the version CRCs.

This has been broken since 2003, commit ("kbuild: Enable modules to be
build using the "make dir/" syntax"). [1]

[1]: https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/commit/?id=15c6240cdc44bbeef3c4797ec860f9765ef4f1a7
Cc: linux-stable <stable@vger.kernel.org> # v2.5.71+
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-01 21:50:43 +09:00
Linus Torvalds
3d77e6a880 Linux 5.7 2020-05-31 16:49:15 -07:00
Nick Desaulniers
10e68b02c8 Makefile: support compressed debug info
As debug information gets larger and larger, it helps significantly save
the size of vmlinux images to compress the information in the debug
information sections. Note: this debug info is typically split off from
the final compressed kernel image, which is why vmlinux is what's used
in conjunction with GDB. Minimizing the debug info size should have no
impact on boot times, or final compressed kernel image size.

All of the debug sections will have a `C` flag set.
$ readelf -S <object file>

$ bloaty vmlinux.gcc75.compressed.dwarf4 -- \
    vmlinux.gcc75.uncompressed.dwarf4

    FILE SIZE        VM SIZE
 --------------  --------------
  +0.0%     +18  [ = ]       0    [Unmapped]
 -73.3%  -114Ki  [ = ]       0    .debug_aranges
 -76.2% -2.01Mi  [ = ]       0    .debug_frame
 -73.6% -2.89Mi  [ = ]       0    .debug_str
 -80.7% -4.66Mi  [ = ]       0    .debug_abbrev
 -82.9% -4.88Mi  [ = ]       0    .debug_ranges
 -70.5% -9.04Mi  [ = ]       0    .debug_line
 -79.3% -10.9Mi  [ = ]       0    .debug_loc
 -39.5% -88.6Mi  [ = ]       0    .debug_info
 -18.2%  -123Mi  [ = ]       0    TOTAL

$ bloaty vmlinux.clang11.compressed.dwarf4 -- \
    vmlinux.clang11.uncompressed.dwarf4

    FILE SIZE        VM SIZE
 --------------  --------------
  +0.0%     +23  [ = ]       0    [Unmapped]
 -65.6%    -871  [ = ]       0    .debug_aranges
 -77.4% -1.84Mi  [ = ]       0    .debug_frame
 -82.9% -2.33Mi  [ = ]       0    .debug_abbrev
 -73.1% -2.43Mi  [ = ]       0    .debug_str
 -84.8% -3.07Mi  [ = ]       0    .debug_ranges
 -65.9% -8.62Mi  [ = ]       0    .debug_line
 -86.2% -40.0Mi  [ = ]       0    .debug_loc
 -42.0% -64.1Mi  [ = ]       0    .debug_info
 -22.1%  -122Mi  [ = ]       0    TOTAL

For x86_64 defconfig + LLVM=1 (before):
Elapsed (wall clock) time (h:mm:ss or m:ss): 3:22.03
Maximum resident set size (kbytes): 43856

For x86_64 defconfig + LLVM=1 (after):
Elapsed (wall clock) time (h:mm:ss or m:ss): 3:32.52
Maximum resident set size (kbytes): 1566776

Thanks to:
Nick Clifton helped us to provide the minimal binutils version.
Sedat Dilek found an increase in size of debug .deb package.

Cc: Nick Clifton <nickc@redhat.com>
Suggested-by: David Blaikie <blaikie@google.com>
Reviewed-by: Fangrui Song <maskray@google.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-29 03:08:49 +09:00
Masahiro Yamada
e9e81b6343 kbuild: disallow multi-word in M= or KBUILD_EXTMOD
$(firstword ...) in scripts/Makefile.modpost was added by commit
3f3fd3c055 ("[PATCH] kbuild: allow multi-word $M in Makefile.modpost")
to build multiple external module directories.

It was a solution to resolve symbol dependencies when an external
module depends on another external module.

Commit 0d96fb20b7 ("kbuild: Add new Kbuild variable
KBUILD_EXTRA_SYMBOLS") introduced another solution by passing symbol
info via KBUILD_EXTRA_SYMBOLS, then broke the multi-word M= support.

  include $(if $(wildcard $(KBUILD_EXTMOD)/Kbuild), \
               $(KBUILD_EXTMOD)/Kbuild, $(KBUILD_EXTMOD)/Makefile)

... does not work if KBUILD_EXTMOD contains multiple words.

This feature has been broken for more than a decade. Remove the
bitrotten code, and stop parsing if M or KBUILD_EXTMOD contains
multiple words.

As Documentation/kbuild/modules.rst explains, if your module depends
on another one, there are two solutions:
  - add a common top-level Kbuild file
  - use KBUILD_EXTRA_SYMBOLS

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-29 03:08:49 +09:00
Masahiro Yamada
b480fec988 kbuild: clear KBUILD_MODULES in top Makefile if CONFIG_MODULES=n
Do not try to build any module-related artifacts when CONFIG_MODULES
is disabled.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Masahiro Yamada
8451791d1f kbuild: make module name conflict fatal error
I think all the warnings have been fixed by now. Make it a fatal error.

Check it before modpost because we need to stop building *.ko files.
Also, pass modules.order via a script parameter.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Masahiro Yamada
121c2a1377 kbuild: error out if targets prefixed with '__' are directly run
Some targets are internal-use only.

It is tedious to care about "what if __build_one_by_one is contained
in $(MAKECMDGOALS)?" etc.

Prefix internal targets with double underscores. Stop parsing Makefile
if they are directly run.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Masahiro Yamada
93fdddfefc kbuild: add this-makefile as a shorthand for $(lastword $(MAKEFILE_LIST))
Make it clearer, and self-documenting.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00
Masahiro Yamada
0663c68c4d kbuild: remove {CLEAN,MRPROPER,DISTCLEAN}_DIRS
Merge {CLEAN,MRPROPER,DISTCLEAN}_DIRS into {CLEAN,MRPROPER,DISTCLEAN}_FILES
because the difference is just the -r option passed to the 'rm' command.

Do likewise as commit 1634f2bfdb ("kbuild: remove clean-dirs syntax").

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:15 +09:00
Masahiro Yamada
610134b750 kbuild: remove misleading stale FIXME comment
This comment was added by commit ("kbuild: Restore build nr, improve
vmlinux link") [1].

It was talking about if_changed_rule at that time. Now, it is unclear
what to fix.

[1]: https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/commit/?id=ea52ca1b3e3882b499cc6c043f384958b88b62ff
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:15 +09:00
Masahiro Yamada
3044dd0528 kbuild: invoke syncconfig if autoconf.h is missing
If include/generated/autoconf.h is accidentally lost somehow,
there is no clear way to fix it. Make it self-healing.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:15 +09:00
Linus Torvalds
9cb1fd0efd Linux 5.7-rc7 2020-05-24 15:32:54 -07:00
Linus Torvalds
b9bbe6ed63 Linux 5.7-rc6 2020-05-17 16:48:37 -07:00
Masahiro Yamada
7f3a59db27 kbuild: add infrastructure to build userspace programs
Kbuild supports the infrastructure to build host programs, but there
was no support to build userspace programs for the target architecture
(i.e. the same architecture as the kernel).

Sam Ravnborg worked on this in 2014 (https://lkml.org/lkml/2014/7/13/154),
but it was not merged. One problem at that time was, there was no good way
to know whether $(CC) can link standalone programs. In fact, pre-built
kernel.org toolchains [1] are often used for building the kernel, but they
do not provide libc.

Now, we can handle this cleanly because the compiler capability is
evaluated at the Kconfig time. If $(CC) cannot link standalone programs,
the relevant options are hidden by 'depends on CC_CAN_LINK'.

The implementation just mimics scripts/Makefile.host

The userspace programs are compiled with the same flags as the host
programs. In addition, it uses -m32 or -m64 if it is found in
$(KBUILD_CFLAGS).

This new syntax has two usecases.

- Sample programs

  Several userspace programs under samples/ include UAPI headers
  installed in usr/include. Most of them were previously built for
  the host architecture just to use the 'hostprogs' syntax.

  However, 'make headers' always works for the target architecture.
  This caused the arch mismatch in cross-compiling. To fix this
  distortion, sample code should be built for the target architecture.

- Bpfilter

  net/bpfilter/Makefile compiles bpfilter_umh as the user mode helper,
  and embeds it into the kernel. Currently, it overrides HOSTCC with
  CC to use the 'hostprogs' syntax. This hack should go away.

[1]: https://mirrors.edge.kernel.org/pub/tools/crosstool/
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2020-05-17 18:52:01 +09:00
Sami Tolvanen
d08b9f0ca6 scs: Add support for Clang's Shadow Call Stack (SCS)
This change adds generic support for Clang's Shadow Call Stack,
which uses a shadow stack to protect return addresses from being
overwritten by an attacker. Details are available here:

  https://clang.llvm.org/docs/ShadowCallStack.html

Note that security guarantees in the kernel differ from the ones
documented for user space. The kernel must store addresses of
shadow stacks in memory, which means an attacker capable reading
and writing arbitrary memory may be able to locate them and hijack
control flow by modifying the stacks.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
[will: Numerous cosmetic changes]
Signed-off-by: Will Deacon <will@kernel.org>
2020-05-15 16:35:45 +01:00
Masahiro Yamada
ea21e90414 kbuild: remove '/' target
This notice has been here for a while. Remove it entirely now.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-12 13:28:33 +09:00
Linus Torvalds
2ef96a5bb1 Linux 5.7-rc5 2020-05-10 15:16:58 -07:00
Linus Torvalds
adc7192096 gcc-10: disable 'restrict' warning for now
gcc-10 now warns about passing aliasing pointers to functions that take
restricted pointers.

That's actually a great warning, and if we ever start using 'restrict'
in the kernel, it might be quite useful.  But right now we don't, and it
turns out that the only thing this warns about is an idiom where we have
declared a few functions to be "printf-like" (which seems to make gcc
pick up the restricted pointer thing), and then we print to the same
buffer that we also use as an input.

And people do that as an odd concatenation pattern, with code like this:

    #define sysfs_show_gen_prop(buffer, fmt, ...) \
        snprintf(buffer, PAGE_SIZE, "%s"fmt, buffer, __VA_ARGS__)

where we have 'buffer' as both the destination of the final result, and
as the initial argument.

Yes, it's a bit questionable.  And outside of the kernel, people do have
standard declarations like

    int snprintf( char *restrict buffer, size_t bufsz,
                  const char *restrict format, ... );

where that output buffer is marked as a restrict pointer that cannot
alias with any other arguments.

But in the context of the kernel, that 'use snprintf() to concatenate to
the end result' does work, and the pattern shows up in multiple places.
And we have not marked our own version of snprintf() as taking restrict
pointers, so the warning is incorrect for now, and gcc picks it up on
its own.

If we do start using 'restrict' in the kernel (and it might be a good
idea if people find places where it matters), we'll need to figure out
how to avoid this issue for snprintf and friends.  But in the meantime,
this warning is not useful.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-09 15:45:21 -07:00
Linus Torvalds
5a76021c2e gcc-10: disable 'stringop-overflow' warning for now
This is the final array bounds warning removal for gcc-10 for now.

Again, the warning is good, and we should re-enable all these warnings
when we have converted all the legacy array declaration cases to
flexible arrays. But in the meantime, it's just noise.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-09 15:40:52 -07:00
Linus Torvalds
44720996e2 gcc-10: disable 'array-bounds' warning for now
This is another fine warning, related to the 'zero-length-bounds' one,
but hitting the same historical code in the kernel.

Because C didn't historically support flexible array members, we have
code that instead uses a one-sized array, the same way we have cases of
zero-sized arrays.

The one-sized arrays come from either not wanting to use the gcc
zero-sized array extension, or from a slight convenience-feature, where
particularly for strings, the size of the structure now includes the
allocation for the final NUL character.

So with a "char name[1];" at the end of a structure, you can do things
like

       v = my_malloc(sizeof(struct vendor) + strlen(name));

and avoid the "+1" for the terminator.

Yes, the modern way to do that is with a flexible array, and using
'offsetof()' instead of 'sizeof()', and adding the "+1" by hand.  That
also technically gets the size "more correct" in that it avoids any
alignment (and thus padding) issues, but this is another long-term
cleanup thing that will not happen for 5.7.

So disable the warning for now, even though it's potentially quite
useful.  Having a slew of warnings that then hide more urgent new issues
is not an improvement.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-09 14:52:44 -07:00
Linus Torvalds
5c45de21a2 gcc-10: disable 'zero-length-bounds' warning for now
This is a fine warning, but we still have a number of zero-length arrays
in the kernel that come from the traditional gcc extension.  Yes, they
are getting converted to flexible arrays, but in the meantime the gcc-10
warning about zero-length bounds is very verbose, and is hiding other
issues.

I missed one actual build failure because it was hidden among hundreds
of lines of warning.  Thankfully I caught it on the second go before
pushing things out, but it convinced me that I really need to disable
the new warnings for now.

We'll hopefully be all done with our conversion to flexible arrays in
the not too distant future, and we can then re-enable this warning.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-09 14:30:29 -07:00
Linus Torvalds
78a5255ffb Stop the ad-hoc games with -Wno-maybe-initialized
We have some rather random rules about when we accept the
"maybe-initialized" warnings, and when we don't.

For example, we consider it unreliable for gcc versions < 4.9, but also
if -O3 is enabled, or if optimizing for size.  And then various kernel
config options disabled it, because they know that they trigger that
warning by confusing gcc sufficiently (ie PROFILE_ALL_BRANCHES).

And now gcc-10 seems to be introducing a lot of those warnings too, so
it falls under the same heading as 4.9 did.

At the same time, we have a very straightforward way to _enable_ that
warning when wanted: use "W=2" to enable more warnings.

So stop playing these ad-hoc games, and just disable that warning by
default, with the known and straight-forward "if you want to work on the
extra compiler warnings, use W=123".

Would it be great to have code that is always so obvious that it never
confuses the compiler whether a variable is used initialized or not?
Yes, it would.  In a perfect world, the compilers would be smarter, and
our source code would be simpler.

That's currently not the world we live in, though.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-09 13:57:10 -07:00
Linus Torvalds
0e698dfa28 Linux 5.7-rc4 2020-05-03 14:56:04 -07:00
Linus Torvalds
6a8b55ed40 Linux 5.7-rc3 2020-04-26 13:51:02 -07:00
Linus Torvalds
ae83d0b416 Linux 5.7-rc2 2020-04-19 14:35:30 -07:00
Ingo Molnar
3b02a051d2 Linux 5.7-rc1
-----BEGIN PGP SIGNATURE-----
 
 iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAl6TbaUeHHRvcnZhbGRz
 QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGhgkH/iWpiKvosA20HJjC
 rBqYeJPxQsgZTuBieWJ+MeVxbpcF7RlM4c+glyvg3QJhHwIEG58dl6LBrQbAyBAR
 aFHNojr1iAYOruVCGnU3pA008YZiwUIDv/ZQ4DF8fmIU2vI2mJ6qHBv3XDl4G2uR
 Nwz8Eu9AgIwZM5coomVOSmoWyFy7Vxmb7W+3t5VmKsvOWx4ib9kyQtOIkvQDEl7j
 XCbWfI0xDQr6LFOm4jnCi5R/LhJ2LIqqIvHHrunbpszM8IwK797jCXz4im+dmd5Y
 +km46N7a8pDqri36xXz1gdBAU3eG7Pt1NyvfjwRVTdX4GquQ2MT0GoojxbLxUP3y
 3pEsQuE=
 =whbL
 -----END PGP SIGNATURE-----

Merge tag 'v5.7-rc1' into locking/kcsan, to resolve conflicts and refresh

Resolve these conflicts:

	arch/x86/Kconfig
	arch/x86/kernel/Makefile

Do a minor "evil merge" to move the KCSAN entry up a bit by a few lines
in the Kconfig to reduce the probability of future conflicts.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-04-13 09:44:39 +02:00
Linus Torvalds
8f3d9f3542 Linux 5.7-rc1 2020-04-12 12:35:55 -07:00
Masahiro Yamada
a0d1c951ef kbuild: support LLVM=1 to switch the default tools to Clang/LLVM
As Documentation/kbuild/llvm.rst implies, building the kernel with a
full set of LLVM tools gets very verbose and unwieldy.

Provide a single switch LLVM=1 to use Clang and LLVM tools instead
of GCC and Binutils. You can pass it from the command line or as an
environment variable.

Please note LLVM=1 does not turn on the integrated assembler. You need
to pass LLVM_IAS=1 to use it. When the upstream kernel is ready for the
integrated assembler, I think we can make it default.

We discussed what we need, and we agreed to go with a simple boolean
flag that switches both target and host tools:

  https://lkml.org/lkml/2020/3/28/494
  https://lkml.org/lkml/2020/4/3/43

Some items discussed, but not adopted:

- LLVM_DIR

  When multiple versions of LLVM are installed, I just thought supporting
  LLVM_DIR=/path/to/my/llvm/bin/ might be useful.

  CC      = $(LLVM_DIR)clang
  LD      = $(LLVM_DIR)ld.lld
    ...

  However, we can handle this by modifying PATH. So, we decided to not do
  this.

- LLVM_SUFFIX

  Some distributions (e.g. Debian) package specific versions of LLVM with
  naming conventions that use the version as a suffix.

  CC      = clang$(LLVM_SUFFIX)
  LD      = ld.lld(LLVM_SUFFIX)
    ...

  will allow a user to pass LLVM_SUFFIX=-11 to use clang-11 etc.,
  but the suffixed versions in /usr/bin/ are symlinks to binaries in
  /usr/lib/llvm-#/bin/, so this can also be handled by PATH.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com> # build
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2020-04-09 03:18:21 +09:00
Masahiro Yamada
7e20e47c70 kbuild: replace AS=clang with LLVM_IAS=1
The 'AS' variable is unused for building the kernel. Only the remaining
usage is to turn on the integrated assembler. A boolean flag is a better
fit for this purpose.

AS=clang was added for experts. So, I replaced it with LLVM_IAS=1,
breaking the backward compatibility.

Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2020-04-09 03:18:09 +09:00
Masahiro Yamada
7273ad2b08 kbuild: link lib-y objects to vmlinux forcibly when CONFIG_MODULES=y
Kbuild supports not only obj-y but also lib-y to list objects linked to
vmlinux.

The difference between them is that all the objects from obj-y are
forcibly linked to vmlinux, whereas the objects from lib-y are linked
as needed; if there is no user of a lib-y object, it is not linked.

lib-y is intended to list utility functions that may be called from all
over the place (and may be unused at all), but it is a problem for
EXPORT_SYMBOL(). Even if there is no call-site in the vmlinux, we need
to keep exported symbols for the use from loadable modules.

Commit 7f2084fa55 ("[kbuild] handle exports in lib-y objects reliably")
worked around it by linking a dummy object, lib-ksyms.o, which contains
references to all the symbols exported from lib.a in that directory.
It uses the linker script command, EXTERN. Unfortunately, the meaning of
EXTERN of ld.lld is different from that of ld.bfd. Therefore, this does
not work with LD=ld.lld (CBL issue #515).

Anyway, the build rule of lib-ksyms.o is somewhat tricky. So, I want to
get rid of it.

At first, I was thinking of accumulating lib-y objects into obj-y
(or even replacing lib-y with obj-y entirely), but the lib-y syntax
is used beyond the ordinary use in lib/ and arch/*/lib/.

Examples:

 - drivers/firmware/efi/libstub/Makefile builds lib.a, which is linked
   into vmlinux in the own way (arm64), or linked to the decompressor
   (arm, x86).

 - arch/alpha/lib/Makefile builds lib.a which is linked not only to
   vmlinux, but also to bootloaders in arch/alpha/boot/Makefile.

 - arch/xtensa/boot/lib/Makefile builds lib.a for use from
   arch/xtensa/boot/boot-redboot/Makefile.

One more thing, adding everything to obj-y would increase the vmlinux
size of allnoconfig (or tinyconfig).

For less impact, I tweaked the destination of lib.a at the top Makefile;
when CONFIG_MODULES=y, lib.a goes to KBUILD_VMLINUX_OBJS, which is
forcibly linked to vmlinux, otherwise lib.a goes to KBUILD_VMLINUX_LIBS
as before.

The size impact for normal usecases is quite small since at lease one
symbol in every lib-y object is eventually called by someone. In case
you are intrested, here are the figures.

x86_64_defconfig:

   text	   data	    bss	    dec	    hex	filename
19566602 5422072 1589328 26578002 1958c52 vmlinux.before
19566932 5422104 1589328 26578364 1958dbc vmlinux.after

The case with the biggest impact is allnoconfig + CONFIG_MODULES=y.

ARCH=x86 allnoconfig + CONFIG_MODULES=y:

   text	   data	    bss	    dec	    hex	filename
1175162	 254740	1220608	2650510	 28718e	vmlinux.before
1177974	 254836	1220608	2653418	 287cea	vmlinux.after

Hopefully this is still not a big deal. The per-file trimming with the
static library is not so effective after all.

If fine-grained optimization is desired, some architectures support
CONFIG_LD_DEAD_CODE_DATA_ELIMINATION, which trims dead code per-symbol
basis. When LTO is supported in mainline, even better optimization will
be possible.

Link: https://github.com/ClangBuiltLinux/linux/issues/515
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reported-by: kbuild test robot <lkp@intel.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2020-04-09 00:13:45 +09:00
Nathan Chancellor
afe956c577 kbuild: Enable -Wtautological-compare
Currently, we disable -Wtautological-compare, which in turn disables a
bunch of more specific tautological comparison warnings that are useful
for the kernel such as -Wtautological-bitwise-compare. See clang's
documentation below for the other warnings that are suppressed by
-Wtautological-compare. Now that all of the major/noisy warnings have
been fixed, enable -Wtautological-compare so that more issues can be
caught at build time by various continuous integration setups.

-Wtautological-constant-out-of-range-compare is kept disabled under a
normal build but visible at W=1 because there are places in the kernel
where a constant or variable size can change based on the kernel
configuration. These are not fixed in a clean/concise way and the ones
I have audited so far appear to be harmless. It is not a subgroup but
rather just one warning so we do not lose out on much coverage by
default.

Link: https://github.com/ClangBuiltLinux/linux/issues/488
Link: http://releases.llvm.org/10.0.0/tools/clang/docs/DiagnosticsReference.html#wtautological-compare
Link: https://bugs.llvm.org/show_bug.cgi?id=42666
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-04-09 00:13:45 +09:00
Linus Torvalds
5b67fbfc32 Kbuild updates for v5.7
[Build system]
 
  - add CONFIG_UNUSED_KSYMS_WHITELIST, which will be useful to define
    a fixed set of export symbols for Generic Kernel Image (GKI)
 
  - allow to run 'make dt_binding_check' without .config
 
  - use full schema for checking DT examples in *.yaml files
 
  - make modpost fail for missing MODULE_IMPORT_NS(), which makes more
    sense because we know the produced modules are never loadable
 
  - Remove unused 'AS' variable
 
 [Kconfig]
 
  - sanitize DEFCONFIG_LIST, and remove ARCH_DEFCONFIG from Kconfig files
 
  - relax the 'imply' behavior so that symbols implied by y can become m
 
  - make 'imply' obey 'depends on' in order to make 'imply' really weak
 
 [Misc]
 
  - add documentation on building the kernel with Clang/LLVM
 
  - revive __HAVE_ARCH_STRLEN for 32bit sparc to use optimized strlen()
 
  - fix warning from deb-pkg builds when CONFIG_DEBUG_INFO=n
 
  - various script and Makefile cleanups
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCgAzFiEEbmPs18K1szRHjPqEPYsBB53g2wYFAl6DbP8VHG1hc2FoaXJv
 eUBrZXJuZWwub3JnAAoJED2LAQed4NsGAfkQALZqMCqtX9cAJej04+lnBCzwVPep
 6s8/s6vW6PF92sHv+SJtHvKSnDekcZT2xT8dkPDaVmuOye8xhENs5dFZ4tSKO5D0
 F8YkkM17mu/cylNZ2UCy/8weh6/TjsD7pa+mFqWo/++30JiXm12v3mVFR568KPXI
 kFau/3ALvY1NIr2wUAI2SOd6A4v/Epzpk0ltnFg3f5iWVFKlE03MGueAF+YZzq7v
 UrU73HdUxF/SBW2Jz3UtV9XY8P38uQmmtoDE8SZikG4PjW03q9w6pnhntDBl/H2b
 dZFg40eG7SHXN4L+OOI32ae9jePHvKpsnjeaeNoT/DZpwpuuxXu7C2EmUy+wCAnM
 Rw4+kiAVNppRMRH1GTdp1XjLY6PwPqizzZGmufwX+W3MI8oZdlLSUJLbrO73P/aF
 QR3MgkJkjvgmRVPP9fr8SNcZ39tDGI4KqLdWvjVVSC/s86aDnw/34puEfw0lj4vs
 gCi923iJQ7Y/QWX63TYZhy96pnedlwE2s6aR1InVER3+XMH9K1nW34CDaKQsp1CB
 6zyrd40+K5ETOKo3OAjq4FttlhRkEpX9nIsffCzOz6tybysHTSrCzYhfjpIAzzYj
 Et5HpXbegHShIqN44yqBumt6YkTZac6Aub9FzInW2LPzZgiofDaNesDQmnQmIZOa
 JlUyBrjXRfwkvCH0
 =wT8A
 -----END PGP SIGNATURE-----

Merge tag 'kbuild-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:
 "Build system:

   - add CONFIG_UNUSED_KSYMS_WHITELIST, which will be useful to define a
     fixed set of export symbols for Generic Kernel Image (GKI)

   - allow to run 'make dt_binding_check' without .config

   - use full schema for checking DT examples in *.yaml files

   - make modpost fail for missing MODULE_IMPORT_NS(), which makes more
     sense because we know the produced modules are never loadable

   - Remove unused 'AS' variable

  Kconfig:

   - sanitize DEFCONFIG_LIST, and remove ARCH_DEFCONFIG from Kconfig
     files

   - relax the 'imply' behavior so that symbols implied by 'y' can
     become 'm'

   - make 'imply' obey 'depends on' in order to make 'imply' really weak

  Misc:

   - add documentation on building the kernel with Clang/LLVM

   - revive __HAVE_ARCH_STRLEN for 32bit sparc to use optimized strlen()

   - fix warning from deb-pkg builds when CONFIG_DEBUG_INFO=n

   - various script and Makefile cleanups"

* tag 'kbuild-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (34 commits)
  Makefile: Update kselftest help information
  kbuild: deb-pkg: fix warning when CONFIG_DEBUG_INFO is unset
  kbuild: add outputmakefile to no-dot-config-targets
  kbuild: remove AS variable
  net: wan: wanxl: refactor the firmware rebuild rule
  net: wan: wanxl: use $(M68KCC) instead of $(M68KAS) for rebuilding firmware
  net: wan: wanxl: use allow to pass CROSS_COMPILE_M68k for rebuilding firmware
  kbuild: add comment about grouped target
  kbuild: add -Wall to KBUILD_HOSTCXXFLAGS
  kconfig: remove unused variable in qconf.cc
  sparc: revive __HAVE_ARCH_STRLEN for 32bit sparc
  kbuild: refactor Makefile.dtbinst more
  kbuild: compute the dtbs_install destination more simply
  Makefile: disallow data races on gcc-10 as well
  kconfig: make 'imply' obey the direct dependency
  kconfig: allow symbols implied by y to become m
  net: drop_monitor: use IS_REACHABLE() to guard net_dm_hw_report()
  modpost: return error if module is missing ns imports and MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS=n
  modpost: rework and consolidate logging interface
  kbuild: allow to run dt_binding_check without kernel configuration
  ...
2020-03-31 16:03:39 -07:00
Shuah Khan
e51d8dacf2 Makefile: Update kselftest help information
Update kselftest help information.

Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-04-01 01:05:04 +09:00
Linus Torvalds
7111951b8d Linux 5.6 2020-03-29 15:25:41 -07:00
David Engraf
4623980dea kbuild: add outputmakefile to no-dot-config-targets
The target outputmakefile is used to generate a Makefile
for out-of-tree builds and does not depend on the kernel
configuration.

Signed-off-by: David Engraf <david.engraf@sysgo.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-03-29 22:37:53 +09:00
Masahiro Yamada
aa824e0c96 kbuild: remove AS variable
As commit 5ef872636c ("kbuild: get rid of misleading $(AS) from
documents") noted, we rarely use $(AS) directly in the kernel build.

Now that the only/last user of $(AS) in drivers/net/wan/Makefile was
converted to $(CC), $(AS) is no longer used in the build process.

You can still pass in AS=clang, which is just a switch to turn on
the LLVM integrated assembler.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
2020-03-29 22:37:53 +09:00
Masahiro Yamada
f463c3510d kbuild: add comment about grouped target
GNU Make commit 8c888d95f618 ("[SV 8297] Implement "grouped targets"
for explicit rules.") added the '&:' syntax.

I think '&:' is a perfect fit here, but we cannot use it any time
soon. Just add a TODO comment.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-03-29 22:37:53 +09:00
Masahiro Yamada
735aab1e00 kbuild: add -Wall to KBUILD_HOSTCXXFLAGS
Add -Wall to catch more warnings for C++ host programs.

When I submitted the previous version, the 0-day bot reported
-Wc++11-compat warnings for old GCC:

  HOSTCXX -fPIC scripts/gcc-plugins/latent_entropy_plugin.o
In file included from /usr/lib/gcc/x86_64-linux-gnu/4.8/plugin/include/tm.h:28:0,
                 from scripts/gcc-plugins/gcc-common.h:15,
                 from scripts/gcc-plugins/latent_entropy_plugin.c:78:
/usr/lib/gcc/x86_64-linux-gnu/4.8/plugin/include/config/elfos.h:102:21: warning: C++11 requires a space between string literal and macro [-Wc++11-compat]
    fprintf ((FILE), "%s"HOST_WIDE_INT_PRINT_UNSIGNED"\n",\
                     ^
/usr/lib/gcc/x86_64-linux-gnu/4.8/plugin/include/config/elfos.h:170:24: warning: C++11 requires a space between string literal and macro [-Wc++11-compat]
       fprintf ((FILE), ","HOST_WIDE_INT_PRINT_UNSIGNED",%u\n",  \
                        ^
In file included from /usr/lib/gcc/x86_64-linux-gnu/4.8/plugin/include/tm.h:42:0,
                 from scripts/gcc-plugins/gcc-common.h:15,
                 from scripts/gcc-plugins/latent_entropy_plugin.c:78:
/usr/lib/gcc/x86_64-linux-gnu/4.8/plugin/include/defaults.h:126:24: warning: C++11 requires a space between string literal and macro [-Wc++11-compat]
       fprintf ((FILE), ","HOST_WIDE_INT_PRINT_UNSIGNED",%u\n",  \
                        ^

The source of the warnings is in the plugin headers, so we have no
control of it. I just suppressed them by adding -Wno-c++11-compat to
scripts/gcc-plugins/Makefile.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Kees Cook <keescook@chromium.org>
2020-03-29 22:37:53 +09:00
Masahiro Yamada
2431f22a91 kbuild: compute the dtbs_install destination more simply
The 'dtbinst_root' is used to remember the root of the in-kernel dts
directory (i.e. arch/*/boot/dts), but it looks clumsy.

I prefer using two variables 'obj' and 'dst' to track the in-kernel
directory and the install destination, respectively.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-03-25 10:19:43 +09:00
Linus Torvalds
16fbf79b0f Linux 5.6-rc7 2020-03-22 18:31:56 -07:00
Ingo Molnar
df10846ff2 Merge branch 'linus' into locking/kcsan, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-03-21 09:35:44 +01:00
Ingo Molnar
a4654e9bde Merge branch 'x86/kdump' into locking/kcsan, to resolve conflicts
Conflicts:
	arch/x86/purgatory/Makefile

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-03-21 09:24:41 +01:00
Linus Torvalds
207f75c454 Kbuild fixes for v5.6 (3rd)
- fix __uint128_t capability test in Kconfig when GCC that defaults
    to 32-bit is used to build the 64-bit kernel
 
  - suppress new noisy Clang warnings -Wpointer-to-enum-cast
 
  - move the namespace field in Module.symvers for the backward
    compatibility reason for the depmod tool
 
  - use available compression for initramdisk when INTRAMFS_SOURCE
    is defined, which was the original behavior
 
  - fix modpost to handle correct large section numbers when it refers
    to modversion CRCs and module namespaces
 
  - fix comments and documents
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCgAzFiEEbmPs18K1szRHjPqEPYsBB53g2wYFAl5zinAVHG1hc2FoaXJv
 eUBrZXJuZWwub3JnAAoJED2LAQed4NsGSTQP/AxHD7mhkT9HLFednPiLS/HaEc1Q
 tgx8xW8DM/BQqFn63sE7ZC8tgPUFe6UAIX94EJ7hC6GHbBf4yaC/+ie5YwsiwzDA
 W5SOFaB9EuBVGLy49+EsOWAzDzJG3L0NN0JhOEc72ACzkOWGPF7+Xr61OqvH4zup
 s3uNAHU22hiFd012eJlEw7sjiEgPgAk4jgNGJLTERcZ+obzeuBIL69CRIME6wK7v
 hJ/35M/XehCyGlt6eKDPdz1fhYV1JxcEsz3BSwcD7L2VrNjU+f5ZOhNFdEedKh9q
 cp0UHmxgJokZpo1mP6g+NPoeSATeyZyPa4LlWsJ4T60/GLXmi/x9rTxiLRIFrWsa
 EC1D6OP8Q2USZaPbEgtUoamVEzyV5aXt8NRToJdeSyajeZHunx7hvUiYRlbff9bm
 VUoVuVxF5EtTGu+UU8FoTdTqHiEzRkjgdd/+9+0kxGBVlApIT3FoL/jYeLhBzxuz
 I1YKuoGjiyivStNKFDRxv/nvDsH44xSOmElZgXS4wItCrYYRTViJcdQ8ua7tTlDV
 ZcApW/fOqVgJSq+YcdX0Ue+A9bzijPKygREr1K1TpoyxiB9RwWNte56pGLe4yvg5
 67qt8PWixBH1AtE6bOa96iTusqqK82xbxgvIScVn1pu9aHVEaGk5g7kBGdaVDRxe
 JsTV4kkF10hgrYxI
 =JTWI
 -----END PGP SIGNATURE-----

Merge tag 'kbuild-fixes-v5.6-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - fix __uint128_t capability test in Kconfig when GCC that defaults to
   32-bit is used to build the 64-bit kernel

 - suppress new noisy Clang warnings -Wpointer-to-enum-cast

 - move the namespace field in Module.symvers for the backward
   compatibility reason for the depmod tool

 - use available compression for initramdisk when INTRAMFS_SOURCE is
   defined, which was the original behavior

 - fix modpost to handle correct large section numbers when it refers to
   modversion CRCs and module namespaces

 - fix comments and documents

* tag 'kbuild-fixes-v5.6-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  scripts/kallsyms: fix wrong kallsyms_relative_base
  modpost: Get proper section index by get_secindex() instead of st_shndx
  initramfs: restore default compression behavior
  modpost: move the namespace field in Module.symvers last
  kbuild: Disable -Wpointer-to-enum-cast
  kbuild: doc: fix references to other documents
  int128: fix __uint128_t compiler test in Kconfig
  kconfig: introduce m32-flag and m64-flag
  kbuild: Fix inconsistent comment
2020-03-19 09:57:48 -07:00
Sergei Trofimovich
b1112139a1 Makefile: disallow data races on gcc-10 as well
gcc-10 will rename --param=allow-store-data-races=0
to -fno-allow-store-data-races.

The flag change happened at https://gcc.gnu.org/PR92046.

Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-03-20 00:34:16 +09:00
Linus Torvalds
fb33c6510d Linux 5.6-rc6 2020-03-15 15:01:23 -07:00
Masahiro Yamada
9dffecc133 kbuild: allow to run dt_binding_check without kernel configuration
The dt_binding_check target is located outside of the
'ifneq ($(dtstree),) ... endif' block.

So, you can run 'make dt_binding_check' on any architecture.
This makes a perfect sense because the dt-schema is arch-agnostic.

The only one problem I see is that scripts/dtc/dtc is not always built.
For example, ARCH=x86 defconfig does not define CONFIG_DTC. Kbuild
descends into scripts/dtc/ with doing nothing. Then, it fails to build
*.example.dt.yaml files.

Let's build scripts/dtc/dtc forcibly when running dt_binding_check.

The dt-schema does not depend on any CONFIG option either, so you
should be able to run dt_binding_check without the .config file.

Going forward, you can directly run 'make dt_binding_check' in a
pristine source tree.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>
2020-03-13 10:04:36 +09:00
Masahiro Yamada
e10c4321dc kbuild: allow to run dt_binding_check and dtbs_check in a single command
Since commit 93512dad33 ("dt-bindings: Improve validation build error
handling"), 'make dtbs_check' does not validate the schema fully.

If you want to check everything, you need to run two commands separately.

  $ make ARCH=arm dt_binding_check
  $ make ARCH=arm dtbs_check

They are exclusive each other, so you cannot do like this:

  $ make ARCH=arm dt_binding_check dtbs_check

In this case, dt-doc-validate and dt-extract-example are skipped
because CHECK_DTBS is set.

Let's make it possible to run these two targets in a single command.
It will be useful for schema writers.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>
2020-03-13 10:04:36 +09:00
Masahiro Yamada
b5154bf63e kbuild: avoid concurrency issue in parallel building dtbs and dtbs_check
'make dtbs_check' checks the shecma in addition to building *.dtb files,
in other words, 'make dtbs_check' is a super-set of 'make dtbs'.
So, you do not have to do 'make dtbs dtbs_check', but I want to keep
the build system as robust as possible in any use.

Currently, 'dtbs' and 'dtbs_check' are independent of each other.
In parallel building, two threads descend into arch/*/boot/dts/,
one for dtbs and the other for dtbs_check, then end up with building
the same DTB simultaneously.

This commit fixes the concurrency issue. Otherwise, I see build errors
like follows:

$ make ARCH=arm64 defconfig
$ make -j16 ARCH=arm64 DT_SCHEMA_FILES=Documentation/devicetree/bindings/arm/psci.yaml dtbs dtbs_check
  <snip>
  DTC     arch/arm64/boot/dts/qcom/sdm845-cheza-r2.dtb
  DTC     arch/arm64/boot/dts/amlogic/meson-gxl-s905x-p212.dtb
  DTC     arch/arm64/boot/dts/allwinner/sun50i-h6-orangepi-lite2.dtb
  DTC     arch/arm64/boot/dts/allwinner/sun50i-h6-orangepi-lite2.dtb
  DTC     arch/arm64/boot/dts/freescale/imx8mn-evk.dtb
  DTC     arch/arm64/boot/dts/allwinner/sun50i-h6-orangepi-one-plus.dtb
  DTC     arch/arm64/boot/dts/zte/zx296718-pcbox.dtb
  DTC     arch/arm64/boot/dts/altera/socfpga_stratix10_socdk.dt.yaml
  DTC     arch/arm64/boot/dts/amlogic/meson-gxl-s905d-p230.dtb
  DTC     arch/arm64/boot/dts/xilinx/zynqmp-zc1254-revA.dtb
  DTC     arch/arm64/boot/dts/allwinner/sun50i-h6-pine-h64.dtb
  DTC     arch/arm64/boot/dts/rockchip/rk3399-gru-scarlet-inx.dtb
  DTC     arch/arm64/boot/dts/allwinner/sun50i-h6-orangepi-one-plus.dtb
  CHECK   arch/arm64/boot/dts/altera/socfpga_stratix10_socdk.dt.yaml
fixdep: error opening file: arch/arm64/boot/dts/allwinner/.sun50i-h6-orangepi-lite2.dtb.d: No such file or directory
make[2]: *** [scripts/Makefile.lib:296: arch/arm64/boot/dts/allwinner/sun50i-h6-orangepi-lite2.dtb] Error 2
make[2]: *** Deleting file 'arch/arm64/boot/dts/allwinner/sun50i-h6-orangepi-lite2.dtb'
make[2]: *** Waiting for unfinished jobs....
  DTC     arch/arm64/boot/dts/rockchip/rk3399-gru-scarlet-kd.dtb
  DTC     arch/arm64/boot/dts/amlogic/meson-gxl-s905d-p231.dtb
  DTC     arch/arm64/boot/dts/xilinx/zynqmp-zc1275-revA.dtb
  DTC     arch/arm64/boot/dts/freescale/imx8mn-ddr4-evk.dtb
fixdep: parse error; no targets found
make[2]: *** [scripts/Makefile.lib:296: arch/arm64/boot/dts/allwinner/sun50i-h6-orangepi-one-plus.dtb] Error 1
make[2]: *** Deleting file 'arch/arm64/boot/dts/allwinner/sun50i-h6-orangepi-one-plus.dtb'
make[1]: *** [scripts/Makefile.build:505: arch/arm64/boot/dts/allwinner] Error 2
make[1]: *** Waiting for unfinished jobs....
  DTC     arch/arm64/boot/dts/renesas/r8a77951-salvator-xs.dtb

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>
2020-03-13 10:04:36 +09:00
SZ Lin (林上智)
46b7c49254 kbuild: Fix inconsistent comment
The commit 2042b5486b ("kbuild: unset variables in top Makefile
instead of setting 0") renamed the variable from "config-targets"
to "config-build", the comment should be consistent accordingly.

Signed-off-by: Kaiden PK Yu (余泊鎧) <KaidenPK.Yu@moxa.com>
Signed-off-by: SZ Lin (林上智) <sz.lin@moxa.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-03-12 07:39:30 +09:00
Linus Torvalds
2c523b344d Linux 5.6-rc5 2020-03-08 17:44:44 -07:00
Quentin Perret
88694cff49 kbuild: generate autoksyms.h early
When doing a cold build, autoksyms.h starts empty, and is updated late
in the build process to have visibility over the symbols used by in-tree
drivers. But since the symbol whitelist is known upfront, it can be used
to pre-populate autoksyms.h and maximize the amount of code that can be
compiled to its final state in a single pass, hence reducing build time.

Do this by using gen_autoksyms.sh to initialize autoksyms.h instead of
creating an empty file.

Acked-by: Nicolas Pitre <nico@fluxnic.net>
Tested-by: Matthias Maennich <maennich@google.com>
Reviewed-by: Matthias Maennich <maennich@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-03-03 20:49:21 +09:00
Masahiro Yamada
2a86f66121 kbuild: use KBUILD_DEFCONFIG as the fallback for DEFCONFIG_LIST
Most of the Kconfig commands (except defconfig and all*config) read
the .config file as a base set of CONFIG options.

When it does not exist, the files in DEFCONFIG_LIST are searched in
this order and loaded if found.

I do not see much sense in the last two lines in DEFCONFIG_LIST.

[1] ARCH_DEFCONFIG

The entry for DEFCONFIG_LIST is guarded by 'depends on !UML'. So, the
ARCH_DEFCONFIG definition in arch/x86/um/Kconfig is meaningless.

arch/{sh,sparc,x86}/Kconfig define ARCH_DEFCONFIG depending on 32 or
64 bit variant symbols. This is a little bit strange; ARCH_DEFCONFIG
should be a fixed string because the base config file is loaded before
the symbol evaluation stage.

Using KBUILD_DEFCONFIG makes more sense because it is fixed before
Kconfig is invoked. Fortunately, arch/{sh,sparc,x86}/Makefile define it
in the same way, and it works as expected. Hence, replace ARCH_DEFCONFIG
with "arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)".

[2] arch/$(ARCH)/defconfig

This file path is no longer valid. The defconfig files are always located
in the arch configs/ directories.

  $ find arch -name defconfig | sort
  arch/alpha/configs/defconfig
  arch/arm64/configs/defconfig
  arch/csky/configs/defconfig
  arch/nds32/configs/defconfig
  arch/riscv/configs/defconfig
  arch/s390/configs/defconfig
  arch/unicore32/configs/defconfig

The path arch/*/configs/defconfig is already covered by
"arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG)". So, this file path is
not necessary.

I moved the default KBUILD_DEFCONFIG to the top Makefile. Otherwise,
the 7 architectures listed above would end up with endless loop of
syncconfig.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-03-03 20:49:21 +09:00
Masahiro Yamada
a83e4ca26a kbuild: remove cc-option switch from -Wframe-larger-than=
This CONFIG option was added by commit 35bb5b1e0e ("Add option to
enable -Wframe-larger-than= on gcc 4.4"). At that time, the cc-option
check was needed.

According to Documentation/process/changes.rst, the current minimal
supported version of GCC is 4.6, so you can assume GCC supports it.
Clang supports it as well.

Remove the cc-option switch and redundant comments.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2020-03-02 21:18:19 +09:00
Linus Torvalds
98d54f81e3 Linux 5.6-rc4 2020-03-01 16:38:46 -06:00
Masahiro Yamada
c473a8d03e kbuild: add dt_binding_check to PHONY in a correct place
The dt_binding_check is added to PHONY, but it is invisible when
$(dtstree) is empty. So, it is not specified as phony for
ARCH=x86 etc.

Add it to PHONY outside the ifneq ... endif block.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Rob Herring <robh@kernel.org>
2020-02-27 02:28:15 +09:00
Masahiro Yamada
964a596db8 kbuild: add dtbs_check to PHONY
The dtbs_check should be a phony target, but currently it is not
specified so.

'make dtbs_check' works even if a file named 'dtbs_check' exists
because it depends on another phony target, scripts_dtc, but we
should not rely on it.

Add dtbs_check to PHONY.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Rob Herring <robh@kernel.org>
2020-02-27 02:26:01 +09:00
Randy Dunlap
505b12b386 kbuild: add comment for V=2 mode
Complete the comments for valid values of KBUILD_VERBOSE,
specifically for KBUILD_VERBOSE=2.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-02-27 02:19:07 +09:00
Linus Torvalds
f8788d86ab Linux 5.6-rc3 2020-02-23 16:17:42 -08:00
Linus Torvalds
11a48a5a18 Linux 5.6-rc2 2020-02-16 13:16:59 -08:00
Linus Torvalds
bb6d3fb354 Linux 5.6-rc1 2020-02-09 16:08:48 -08:00
Masahiro Yamada
f566e1fbad kbuild: make multiple directory targets work
Currently, the single-target build does not work when two
or more sub-directories are given:

  $ make fs/ kernel/ lib/
    CALL    scripts/checksyscalls.sh
    CALL    scripts/atomic/check-atomics.sh
    DESCEND  objtool
  make[2]: Nothing to be done for 'kernel/'.
  make[2]: Nothing to be done for 'fs/'.
  make[2]: Nothing to be done for 'lib/'.

Make it work properly.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-02-06 06:31:51 +09:00
Linus Torvalds
368d060bb4 Kbuild updates for v5.6
- detect missing include guard in UAPI headers
 
  - do not create orphan built-in.a or obj-y objects
 
  - generate modules.builtin more simply, and drop tristate.conf
 
  - simplify built-in initramfs creation
 
  - make linux-headers deb package thinner
 
  - optimize the deb package build script
 
  - misc cleanups
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCgAzFiEEbmPs18K1szRHjPqEPYsBB53g2wYFAl409uwVHG1hc2FoaXJv
 eUBrZXJuZWwub3JnAAoJED2LAQed4NsG6vAP/jky7LSuv6lpIcYhxOmzFfs7qTlA
 llZDmzTPi26/doV1P9LYMw6Pd4HV6Zeo/aFLolirCsp0kFBW/5b2C68OsXfotJOD
 0YxPeFMIsumsmAVdQ7lGQerS19BDcMrFJiKoLUuULH3bH0mjL/YVlFVg0Dmq77j1
 PDsyTihROajVmJBf8UMK65nUdCSLZihBsKyvj7SxYnlHAS1EaAT+RiwE7qAHoYW9
 C3TYwOa1e8u/0FmosKxSChl9Pq5ti/gcK4dVLs7bm4LmJEsqmLeR8BDM8xlaT/FE
 lFl7iPLO2cvhy76NsK8YBnTcRD445gBn+M3XFKZ3sDTVj7TkdaIWtVurf5IYo+BN
 bTJHac1E9nbpv6L7QIXhxLCGozEi0+pv/8pyhIrAv8XxmZXp7HJbon+siEg8Glez
 rbwM44kNPQk8xovVcoixh4+qRH9l49+zzT0h0kY1PWfJ6hp0D1xmG/v3kai8dErt
 X4w7xi5gOssYwZ5M0LuOQprDeL5DV/Caz5R1+maqVb2yhn2EBsJ6wC24/vawxhFj
 Kjx1g/NZIW4lnBrF1Ay4geF+f+0jd1bcTBqtNmC09uSTIBvEysZ3HNBf4Z9PFTGW
 jdQ7Qpowgy9SOLqZuE+OAuojq7xhfm1fkm/MBUFUYh/HKOXoiLAnVK1+x0BM0yJB
 ZhMwvmj9fKoqVpzx
 =i/xZ
 -----END PGP SIGNATURE-----

Merge tag 'kbuild-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - detect missing include guard in UAPI headers

 - do not create orphan built-in.a or obj-y objects

 - generate modules.builtin more simply, and drop tristate.conf

 - simplify built-in initramfs creation

 - make linux-headers deb package thinner

 - optimize the deb package build script

 - misc cleanups

* tag 'kbuild-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (34 commits)
  builddeb: split libc headers deployment out into a function
  builddeb: split kernel headers deployment out into a function
  builddeb: remove redundant make for ARCH=um
  builddeb: avoid invoking sub-shells where possible
  builddeb: remove redundant $objtree/
  builddeb: match temporary directory name to the package name
  builddeb: remove unneeded files in hdrobjfiles for headers package
  kbuild: use -S instead of -E for precise cc-option test in Kconfig
  builddeb: allow selection of .deb compressor
  kbuild: remove 'Building modules, stage 2.' log
  kbuild: remove *.tmp file when filechk fails
  kbuild: remove PYTHON2 variable
  modpost: assume STT_SPARC_REGISTER is defined
  gen_initramfs.sh: remove intermediate cpio_list on errors
  initramfs: refactor the initramfs build rules
  gen_initramfs.sh: always output cpio even without -o option
  initramfs: add default_cpio_list, and delete -d option support
  initramfs: generate dependency list and cpio at the same time
  initramfs: specify $(src)/gen_initramfs.sh as a prerequisite in Makefile
  initramfs: make initramfs compression choice non-optional
  ...
2020-02-01 10:01:52 -08:00
Linus Torvalds
d5226fa6db Linux 5.5 2020-01-26 16:23:03 -08:00
Ingo Molnar
837171fe77 Linux 5.5-rc7
-----BEGIN PGP SIGNATURE-----
 
 iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAl4k7i8eHHRvcnZhbGRz
 QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGvk0IAKRenVOdiudY77SQ
 VZjsteyrYTTQtPPv494ToIRjR0XQ+gYp8vyWzXTUC5Nm9Y9U3VzDqUPUjWszrSXE
 6mU+tzcMc9qwuUxnIFn8zfg64ygw+37sn/w3xqeH4QmF9Z5Wl3EX3SdXTs7jp3RS
 VxiztkUNI5ZBV2GDtla5K/9qLPqCQnUYXIiyi5lAtBtiitZDVXFp7dy7hMgEiaEO
 +78K5Kh3xlt5ndDsBFOlwIb2Oof3KL7bBXntdbSBc/bjol6IRvAgln48HWCv59G2
 jzAp2tj2KobX9GRAEPj+v4TQZEW0SXDNDi8MgQsM+3DYVCTmANsv57CBKRuf01+F
 nB1kAys=
 =zSnJ
 -----END PGP SIGNATURE-----

Merge tag 'v5.5-rc7' into locking/kcsan, to refresh the tree

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-01-20 08:42:47 +01:00
Linus Torvalds
def9d27807 Linux 5.5-rc7 2020-01-19 16:02:49 -08:00
Masahiro Yamada
94f7345b71 kbuild: remove PYTHON2 variable
Python 2 has retired. There is no user of this variable.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-01-16 00:26:22 +09:00
Linus Torvalds
b3a987b026 Linux 5.5-rc6 2020-01-12 16:55:08 -08:00
Masahiro Yamada
8b41fc4454 kbuild: create modules.builtin without Makefile.modbuiltin or tristate.conf
Commit bc081dd6e9 ("kbuild: generate modules.builtin") added
infrastructure to generate modules.builtin, the list of all
builtin modules.

Basically, it works like this:

  - Kconfig generates include/config/tristate.conf, the list of
    tristate CONFIG options with a value in a capital letter.

  - scripts/Makefile.modbuiltin makes Kbuild descend into
    directories to collect the information of builtin modules.

I am not a big fan of it because Kbuild ends up with traversing
the source tree twice.

I am not sure how perfectly it should work, but this approach cannot
avoid false positives; even if the relevant CONFIG option is tristate,
some Makefiles forces obj-m to obj-y.

Some examples are:

  arch/powerpc/platforms/powermac/Makefile:
    obj-$(CONFIG_NVRAM:m=y)         += nvram.o

  net/ipv6/Makefile:
    obj-$(subst m,y,$(CONFIG_IPV6)) += inet6_hashtables.o

  net/netlabel/Makefile:
    obj-$(subst m,y,$(CONFIG_IPV6)) += netlabel_calipso.o

Nobody has complained about (or noticed) it, so it is probably fine to
have false positives in modules.builtin.

This commit simplifies the implementation. Let's exploit the fact
that every module has MODULE_LICENSE(). (modpost shows a warning if
MODULE_LICENSE is missing. If so, 0-day bot would already have blocked
such a module.)

I added MODULE_FILE to <linux/module.h>. When the code is being compiled
as builtin, it will be filled with the file path of the module, and
collected into modules.builtin.info. Then, scripts/link-vmlinux.sh
extracts the list of builtin modules out of it.

This new approach fixes the false-positives above, but adds another
type of false-positives; non-modular code may have MODULE_LICENSE()
by mistake. This is not a big deal, it is just the code is always
orphan. We can clean it up if we like. You can see cleanup examples by:

  $ git log --grep='make.* explicitly non-modular'

To sum up, this commits deletes lots of code, but still produces almost
equivalent results. Please note it does not increase the vmlinux size at
all. As you can see in include/asm-generic/vmlinux.lds.h, the .modinfo
section is discarded in the link stage.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-01-07 02:18:39 +09:00
Ingo Molnar
31c7ac388a Linux 5.5-rc5
-----BEGIN PGP SIGNATURE-----
 
 iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAl4SYegeHHRvcnZhbGRz
 QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiG4m4H+QGCUN8SXN+2B+0/
 BfzOf7PFoKzAx3NwDbJQIZqhSl+Zfa4n3VGPEF8sXsvoQgdYvuJnS/5JiAZ9iRIH
 HAfFzegzQ3mCl8Du+SqCvQKs2Jt4OMCX62KGRebRBhpoKfZdwmN7n7pn9lWO771K
 9rxTpeItXhmK46jOFRbi5oyQfmkfSfyUN1b9CB53FXFS+ZDkDNA7QQiIYnKOD7SZ
 RrL7czhZ580QOC61qOlnz1GIhRzvU5SXg4OtuI3YfoOJRY5FKC3YtOgLReT0vPs+
 vEhAyP93upVXIhqm10WHNjd4t4a45Vy5ff64uFsQ9QV4nnqsC2C70YwWbVDdtz/W
 Lm0mvE8=
 =NECs
 -----END PGP SIGNATURE-----

Merge tag 'v5.5-rc5' into locking/kcsan, to resolve conflict

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-01-06 07:51:15 +01:00
Linus Torvalds
c79f46a282 Linux 5.5-rc5 2020-01-05 14:23:27 -08:00
Ingo Molnar
28336be568 Linux 5.5-rc4
-----BEGIN PGP SIGNATURE-----
 
 iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAl4JNtkeHHRvcnZhbGRz
 QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGdN0H/3UI6LHOx1ol3/7L
 TwgMibg2pNxNU05bowDjQt92+Hgj9JM0TeFBsfr5hLaeKBgeVCPr5xK/vH09NlKu
 otVGbhBLpl9OAUu9znTfbt4bcqhJKlr/K0mS5e1vPsXvZ3wdHS27trwjgyu16/pP
 NJwkcs5/VRYVC/SrZay2NvheKN+DoGSd4+ZlJprwtAAVMdbEvoaGqRLGKLfLeDMc
 Z04w8AKhnKIxSkt+eEmuW9+pAQJUAkk4QVjixcJe8q0QpA1XIj965yvE8+XpjbLo
 eFxupmZq4S2JdCjsa+iBferJ5juR1FVhbHSbZtLsTtkPVegI9ug911WQ+KiCqErI
 VkiKUl8=
 =rNsn
 -----END PGP SIGNATURE-----

Merge tag 'v5.5-rc4' into locking/kcsan, to resolve conflicts

Conflicts:
	init/main.c
	lib/Kconfig.debug

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-30 08:10:51 +01:00
Linus Torvalds
fd6988496e Linux 5.5-rc4 2019-12-29 15:29:16 -08:00
Linus Torvalds
46cf053efe Linux 5.5-rc3 2019-12-22 17:02:23 -08:00
Linus Torvalds
6c1c79a5f4 Kbuild fixes for v5.5
- fix warning in out-of-tree 'make clean'
 
  - add READELF variable to the top Makefile
 
  - fix broken builds when LINUX_COMPILE_BY contains a backslash
 
  - fix build warning in kallsyms
 
  - fix NULL pointer access in expr_eq() in Kconfig
 
  - fix missing dependency on rsync in deb-pkg build
 
  - remove ---help--- from documentation
 
  - fix misleading documentation about directory descending
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCgAzFiEEbmPs18K1szRHjPqEPYsBB53g2wYFAl3+OssVHG1hc2FoaXJv
 eUBrZXJuZWwub3JnAAoJED2LAQed4NsGCccP/ROhTMQviPaj1W8qgE5r18Yh5U7H
 8f3h2OuqX2mVn6Jnqhs83JvuAKKENczh884MCgvmZCq4eVGkxB5yigZjctpQYzpR
 hpLZRSCfv415wSTZOttsVmff4ovrJ0KpYfx6cMOTK7Hm+4UBRtDMK2xjE+x4ZNmH
 dX04q3oA5eoc1jx2cqP5nltiwFbfEk1hx8s9QwXc9JysYTlUbJZ4SQE7NGGEdk5+
 rZOA9koJOpcbqcGMjMusApD2lzl2RgP2/fbLdA68zlgpUV9xT3GiieQiSAkIi8gh
 +PcWjWVoZyuQUMeGG+3HmnUVfBaIGXxWLfERbB5LZEftUS7HRS5+i2DHvla67gPp
 alqxtz1sE5VeEmkq+msdrnZxqakNP5EjLnCa57BkVvRRphtKy1gijN9FuT8mjZUz
 UJA7CYhB2HIcwSzJIosRPhIhNudwpZidWU0nnjxmEatVgL5y2UG1UNe9Wfmh45Gf
 fNYQSMwL+LL/xiO2E1WACBqAhCfvGbCG3NEinO1IAe0SuMtF2Ha77Fo3CKqFtLyu
 ROB3ffuADIWID/tKe02BOnACcHXjHV0XEOc9CjRmn9pMw109Wy03EdfzgQyULTU7
 qKOWeE+dcnsoLwnUGrWzaqaqH3yADVy9pIKLYKtD/Veu6lLL3kJ1dOIdr6spSICO
 Ji3f8/3ADS8jJh/a
 =OKOu
 -----END PGP SIGNATURE-----

Merge tag 'kbuild-fixes-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - fix warning in out-of-tree 'make clean'

 - add READELF variable to the top Makefile

 - fix broken builds when LINUX_COMPILE_BY contains a backslash

 - fix build warning in kallsyms

 - fix NULL pointer access in expr_eq() in Kconfig

 - fix missing dependency on rsync in deb-pkg build

 - remove ---help--- from documentation

 - fix misleading documentation about directory descending

* tag 'kbuild-fixes-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: clarify the difference between obj-y and obj-m w.r.t. descending
  kconfig: remove ---help--- from documentation
  scripts: package: mkdebian: add missing rsync dependency
  kconfig: don't crash on NULL expressions in expr_eq()
  scripts/kallsyms: fix offset overflow of kallsyms_relative_base
  mkcompile_h: use printf for LINUX_COMPILE_BY
  mkcompile_h: git rid of UTS_TRUNCATE from LINUX_COMPILE_{BY,HOST}
  x86/boot: kbuild: allow readelf executable to be specified
  kbuild: fix 'No such file or directory' warning when cleaning
2019-12-21 10:49:47 -08:00
Linus Torvalds
d1eef1c619 Linux 5.5-rc2 2019-12-15 15:16:08 -08:00
Dmitry Golovin
eefb8c124f x86/boot: kbuild: allow readelf executable to be specified
Introduce a new READELF variable to top-level Makefile, so the name of
readelf binary can be specified.

Before this change the name of the binary was hardcoded to
"$(CROSS_COMPILE)readelf" which might not be present for every
toolchain.

This allows to build with LLVM Object Reader by using make parameter
READELF=llvm-readelf.

Link: https://github.com/ClangBuiltLinux/linux/issues/771
Signed-off-by: Dmitry Golovin <dima@golovin.in>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2019-12-14 15:53:04 +09:00
Linus Torvalds
e42617b825 Linux 5.5-rc1 2019-12-08 14:57:55 -08:00
Linus Torvalds
76bb8b0596 Kbuild updates for v5.5
- remove unneeded asm headers from hexagon, ia64
 
  - add 'dir-pkg' target, which works like 'tar-pkg' but skips archiving
 
  - add 'helpnewconfig' target, which shows help for new CONFIG options
 
  - support 'make nsdeps' for external modules
 
  - make rebuilds faster by deleting $(wildcard $^) checks
 
  - remove compile tests for kernel-space headers
 
  - refactor modpost to simplify modversion handling
 
  - make single target builds faster
 
  - optimize and clean up scripts/kallsyms.c
 
  - refactor various Makefiles and scripts
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCgAzFiEEbmPs18K1szRHjPqEPYsBB53g2wYFAl3lKCUVHG1hc2FoaXJv
 eUBrZXJuZWwub3JnAAoJED2LAQed4NsGu9sP/iTW/RjDxbAsu0aP8jFqzLK/xKB/
 NQn/+dD76TjEmjgew9AXszf2rJL+ixKVymGM08FV59Bbguvi8XmAB/QXK21Sjb5j
 rVl3N97TWNkvXM+QJyly23G2UtbubRSPo3g+e70BZrw3lcmrsK+sAmTOL5KtIrNX
 9BHM803JwqsMJyvBwTBBw3UFeeBqb38Qx6gmigfSihuDf6pvjoVDKskpsDno3wX7
 rdiXYxAsKQLQ/P2ym/bV/Oqe90RqRtV/2/WCpLshlwHkiM9huflv6GjgCkkbAx5H
 N3TSptlS7l/2B/XKHgA5ALjHjUlxTGBzLLoevarCd8loKcQXFlgx+vd3nM/WJlHJ
 x9UpTklDwGP9eUBsa9W980tEyUVsFGMAC8EcTdW6NN2IRtuCOSA5N2FYYt8/SDd0
 2b3PhElTJIp4pTWSYN6JZxB1R8n/YBgxLqOJ6N2U6B9CdKFUCHlwGH23QfN89km/
 WEMP85bsaab/dnyxbwelkoYYYyPgUHsC13AbpkHdrDxMbAGO+G1PwpHxC6ErF2en
 wRGrcUxWTfHRykO5aJIQtCB9b1fv73134mTzB5fTYd6GtjepGBSBCO9xb2Iy4sc9
 Y+nHVVDUrihvSOpJgqh677PcLDutOZR8fFCoc1ZMDAbBsDvrb0Qsee6oEidj98xc
 5kXp9YZh/tdh/tdo
 =zUaB
 -----END PGP SIGNATURE-----

Merge tag 'kbuild-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - remove unneeded asm headers from hexagon, ia64

 - add 'dir-pkg' target, which works like 'tar-pkg' but skips archiving

 - add 'helpnewconfig' target, which shows help for new CONFIG options

 - support 'make nsdeps' for external modules

 - make rebuilds faster by deleting $(wildcard $^) checks

 - remove compile tests for kernel-space headers

 - refactor modpost to simplify modversion handling

 - make single target builds faster

 - optimize and clean up scripts/kallsyms.c

 - refactor various Makefiles and scripts

* tag 'kbuild-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (59 commits)
  MAINTAINERS: update Kbuild/Kconfig maintainer's email address
  scripts/kallsyms: remove redundant initializers
  scripts/kallsyms: put check_symbol_range() calls close together
  scripts/kallsyms: make check_symbol_range() void function
  scripts/kallsyms: move ignored symbol types to is_ignored_symbol()
  scripts/kallsyms: move more patterns to the ignored_prefixes array
  scripts/kallsyms: skip ignored symbols very early
  scripts/kallsyms: add const qualifiers where possible
  scripts/kallsyms: make find_token() return (unsigned char *)
  scripts/kallsyms: replace prefix_underscores_count() with strspn()
  scripts/kallsyms: add sym_name() to mitigate cast ugliness
  scripts/kallsyms: remove unneeded length check for prefix matching
  scripts/kallsyms: remove redundant is_arm_mapping_symbol()
  scripts/kallsyms: set relative_base more effectively
  scripts/kallsyms: shrink table before sorting it
  scripts/kallsyms: fix definitely-lost memory leak
  scripts/kallsyms: remove unneeded #ifndef ARRAY_SIZE
  kbuild: make single target builds even faster
  modpost: respect the previous export when 'exported twice' is warned
  modpost: do not set ->preloaded for symbols from Module.symvers
  ...
2019-12-02 17:35:04 -08:00
Linus Torvalds
219d54332a Linux 5.4 2019-11-24 16:32:01 -08:00
Masahiro Yamada
b1fbfcb4a2 kbuild: make single target builds even faster
Commit 2dffd23f81 ("kbuild: make single target builds much faster")
made the situation much better.

To improve it even more, apply the similar idea to the top Makefile.
Trim unrelated directories from build-dirs.

The single build code must be moved above the 'descend' target.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Jens Axboe <axboe@kernel.dk>
2019-11-23 15:46:42 +09:00
Ingo Molnar
8e1d58ae0c Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into locking/kcsan
Pull the KCSAN subsystem from Paul E. McKenney:

   "This pull request contains base kernel concurrency sanitizer
    (KCSAN) enablement for x86, courtesy of Marco Elver.  KCSAN is a
    sampling watchpoint-based data-race detector, and is documented in
    Documentation/dev-tools/kcsan.rst.  KCSAN was announced in September,
    and much feedback has since been incorporated:

      http://lkml.kernel.org/r/CANpmjNPJ_bHjfLZCAPV23AXFfiPiyXXqqu72n6TgWzb2Gnu1eA@mail.gmail.com

    The data races located thus far have resulted in a number of fixes:

      https://github.com/google/ktsan/wiki/KCSAN#upstream-fixes-of-data-races-found-by-kcsan

    Additional information may be found here:

      https://lore.kernel.org/lkml/20191114180303.66955-1-elver@google.com/
   "

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-19 19:56:28 +01:00
Linus Torvalds
af42d3466b Linux 5.4-rc8 2019-11-17 14:47:30 -08:00
Marco Elver
dfd402a4c4 kcsan: Add Kernel Concurrency Sanitizer infrastructure
Kernel Concurrency Sanitizer (KCSAN) is a dynamic data-race detector for
kernel space. KCSAN is a sampling watchpoint-based data-race detector.
See the included Documentation/dev-tools/kcsan.rst for more details.

This patch adds basic infrastructure, but does not yet enable KCSAN for
any architecture.

Signed-off-by: Marco Elver <elver@google.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2019-11-16 07:23:13 -08:00
Masahiro Yamada
7ecaf069da kbuild: move headers_check rule to usr/include/Makefile
Currently, some sanity checks for uapi headers are done by
scripts/headers_check.pl, which is wired up to the 'headers_check'
target in the top Makefile.

It is true compiling headers has better test coverage, but there
are still several headers excluded from the compile test. I like
to keep headers_check.pl for a while, but we can delete a lot of
code by moving the build rule to usr/include/Makefile.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-11-15 00:23:10 +09:00
Masahiro Yamada
fcbb8461fd kbuild: remove header compile test
There are both positive and negative options about this feature.
At first, I thought it was a good idea, but actually Linus stated a
negative opinion (https://lkml.org/lkml/2019/9/29/227). I admit it
is ugly and annoying.

The baseline I'd like to keep is the compile-test of uapi headers.
(Otherwise, kernel developers have no way to ensure the correctness
of the exported headers.)

I will maintain a small build rule in usr/include/Makefile.
Remove the other header test functionality.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-11-15 00:22:35 +09:00
Luc Van Oostenryck
80591e61a0 kbuild: tell sparse about the $ARCH
Sparse uses the same executable for all archs and uses flags
like -m64, -mbig-endian or -D__arm__ for arch-specific parameters.
But Sparse also uses value from the host machine used to build
Sparse as default value for the target machine.

This works, of course, well for native build but can create
problems when cross-compiling, like defining both '__i386__'
and '__arm__' when cross-compiling for arm on a x86-64 machine.

Fix this by explicitely telling sparse the target architecture.

Reported-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-11-15 00:13:23 +09:00
Masahiro Yamada
bc35d4bda2 scripts/nsdeps: support nsdeps for external module builds
scripts/nsdeps is written to take care of only in-tree modules.
Perhaps, this is not a bug, but just a design. At least,
Documentation/core-api/symbol-namespaces.rst focuses on in-tree modules.

Having said that, some people already tried nsdeps for external modules.
So, it would be nice to support it.

Reported-by: Steve French <smfrench@gmail.com>
Reported-by: Jessica Yu <jeyu@kernel.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Jessica Yu <jeyu@kernel.org>
Acked-by: Jessica Yu <jeyu@kernel.org>
Reviewed-by: Matthias Maennich <maennich@google.com>
Tested-by: Matthias Maennich <maennich@google.com>
2019-11-11 20:10:01 +09:00
Masahiro Yamada
bbc55bded4 modpost: dump missing namespaces into a single modules.nsdeps file
The modpost, with the -d option given, generates per-module .ns_deps
files.

Kbuild generates per-module .mod files to carry module information.
This is convenient because Make handles multiple jobs in parallel
when the -j option is given.

On the other hand, the modpost always runs as a single thread.
I do not see a strong reason to produce separate .ns_deps files.

This commit changes the modpost to generate just one file,
modules.nsdeps, each line of which has the following format:

  <module_name>: <list of missing namespaces>

Please note it contains *missing* namespaces instead of required ones.
So, modules.nsdeps is empty if the namespace dependency is all good.

This will work more efficiently because spatch will no longer process
already imported namespaces. I removed the '(if needed)' from the
nsdeps log since spatch is invoked only when needed.

This also solves the stale .ns_deps problem reported by Jessica Yu:

  https://lkml.org/lkml/2019/10/28/467

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Jessica Yu <jeyu@kernel.org>
Acked-by: Jessica Yu <jeyu@kernel.org>
Reviewed-by: Matthias Maennich <maennich@google.com>
Tested-by: Matthias Maennich <maennich@google.com>
2019-11-11 20:10:01 +09:00
Masahiro Yamada
bff9c62b5d modpost: do not invoke extra modpost for nsdeps
'make nsdeps' invokes the modpost three times at most; before linking
vmlinux, before building modules, and finally for generating .ns_deps
files. Running the modpost again and again is not efficient.

The last two can be unified. When the -d option is given, the modpost
still does the usual job, and in addition, generates .ns_deps files.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Matthias Maennich <maennich@google.com>
Reviewed-by: Matthias Maennich <maennich@google.com>
2019-11-11 20:10:01 +09:00
Geert Uytterhoeven
4234448b70 kbuild: Extend defconfig field size from 24 to 27
There are 6 defconfigs with names longer than 24 characters, breaking
alignment in "make help".

The "winner" is "ecovec24-romimage_defconfig", counting in at 27
characters.

Extend the defconfig field size to 27 to restore alignment.
Don't use a larger value, to not encourage people to create even longer
defconfig names.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-11-11 20:10:01 +09:00
Geert Uytterhoeven
a64c0440dd kbuild: Wrap long "make help" text lines
Some "make help" text lines extend beyond 80 characters.
Wrap them before an opening parenthesis, or before 80 characters.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-11-11 20:10:01 +09:00