Commit Graph

537 Commits

Author SHA1 Message Date
Will McVicker
da2089a28a ANDROID: modules: introduce the MODULE_SCMVERSION config
Config MODULE_SCMVERSION introduces a new module attribute --
`scmversion` -- which can be used to identify a given module's SCM
version.  This is very useful for developers that update their kernel
independently from their kernel modules or vice-versa since the SCM
version provided by UTS_RELEASE (`uname -r`) will now differ from the
module's vermagic attribute.

For example, we have a CI setup that tests new kernel changes on the
hikey960 and db845c devices without updating their kernel modules. When
these tests fail, we need to be able to identify the exact device
configuration the test was using. By including MODULE_SCMVERSION, we can
identify the exact kernel and modules' SCM versions for debugging the
failures.

Additionally, by exposing the SCM version via the sysfs node
/sys/module/MODULENAME/scmversion, one can also verify the SCM versions
of the modules loaded from the initramfs. Currently, modinfo can only
retrieve module attributes from the module's ko on disk and not from the
actual module that is loaded in RAM.

You can retrieve the SCM version in two ways,

1) By using modinfo:
    > modinfo -F scmversion MODULENAME
2) By module sysfs node:
    > cat /sys/module/MODULENAME/scmversion

Bug: 180027765
Link: https://lore.kernel.org/lkml/20210121213641.3477522-1-willmcvicker@google.com
Signed-off-by: Will McVicker <willmcvicker@google.com>
Change-Id: Ib7c72c72f95c4545adb7cd4e842729557039ce3a
2021-02-23 16:42:21 -08:00
Quentin Perret
ef84e87362 UPSTREAM: modpost: turn static exports into error
Using EXPORT_SYMBOL*() on static functions is fundamentally wrong.
Modpost currently reports that as a warning, but clearly this is not a
pattern we should allow, and all in-tree occurences should have been
fixed by now. So, promote the warn() message to error() to make sure
this never happens again.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Matthias Maennich <maennich@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Bug: 176428324
Change-Id: I0084ff44b38e68ac2e2ed1818a7cc1bd09cfb58c
(cherry picked from commit b9ed847b5ae69e0f2e685f9d53e2dd94c0db751e)
Signed-off-by: Melody Olvera <molvera@codeaurora.org>
2021-02-01 08:21:44 +00:00
Melody Olvera
ff6d1ce0ac Revert "FROMLIST: modpost: Make static exports fatal"
This reverts commit db78f3b149.

Reason for revert: Pulling upstream changes which accomplish the same thing.
See https://android-review.googlesource.com/c/kernel/common/+/1559676

Bug: 176428324
Change-Id: I924e794d9987994d88aa0e6c11e1062e2b046947
Signed-off-by: Melody Olvera <molvera@codeaurora.org>
2021-02-01 08:21:33 +00:00
Masahiro Yamada
1e58260d76 UPSTREAM: modpost: turn section mismatches to error from fatal()
There is code that reports static EXPORT_SYMBOL a few lines below.
It is not a good idea to bail out here.

I renamed sec_mismatch_fatal to sec_mismatch_warn_only (with logical
inversion) to match to CONFIG_SECTION_MISMATCH_WARN_ONLY.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Bug: 176428324
Change-Id: Ic03aaa279306cf76ba224bee37c89ee689c658a6
(cherry picked from commit c7299d98c00afa81c65d9fa13a18ea923f3281ff)
Signed-off-by: Melody Olvera <molvera@codeaurora.org>
2021-02-01 08:21:22 +00:00
Masahiro Yamada
2a30bb9b7b UPSTREAM: modpost: change license incompatibility to error() from fatal()
Change fatal() to error() to continue running to report more possible
issues.

There is no difference in the fact that modpost will fail anyway.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Bug: 176428324
Change-Id: Ifaf5378d9305e6a5711cbe2d49b578c6ef184000
(cherry picked from commit d6d692fa21d3057edf457a764832077da8aa44d2)
Signed-off-by: Melody Olvera <molvera@codeaurora.org>
2021-02-01 08:21:07 +00:00
Masahiro Yamada
1731b01108 UPSTREAM: modpost: turn missing MODULE_LICENSE() into error
Do not create modules with no license tag.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Bug: 176428324
Change-Id: Iab31389b56545baa6d54c59b7ff2fc72c6c1876e
(cherry picked from commit 1d6cd39293602e990b016994e51956eded35da7c)
Signed-off-by: Melody Olvera <molvera@codeaurora.org>
2021-02-01 08:20:55 +00:00
Masahiro Yamada
ba0f642827 UPSTREAM: modpost: refactor error handling and clarify error/fatal difference
We have 3 log functions. fatal() is special because it lets modpost bail
out immediately. The difference between warn() and error() is the only
prefix parts ("WARNING:" vs "ERROR:").

The intended usage of error() is probably to propagate the return code
from the function to the exit code of modpost, as check_exports() etc.
already does. This is a good manner because we should display as many
issues as possible in a single run of modpost.

What is annoying about fatal() is that it kills modpost at the first
error. People would need to run Kbuild again and again until they fix
all errors.

But, unfortunately, people tend to do:
"This case should not be allowed. Let's replace warn() with fatal()."

One of the reasons is probably it is tedious to manually carry the error
code back to the main() function.

This commit refactors error() so any single call for it automatically
makes modpost return the error code.

I also added comments in modpost.h for warn(), error(), and fatal().

Again, please use fatal() only when you have a strong reason to do so.
For example:

  - Memory shortage (i.e. malloc() etc. has failed)
  - The ELF file is broken, and there is no point to continue parsing
  - Something really odd has happened

For general coding errors, please use error().

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Quentin Perret <qperret@google.com>

Bug: 176428324
Change-Id: I1f2029e91cbe5a381efce38b148fc1beafe224e5
(cherry picked from commit 0fd3fbadd9a85e391828f3ef63ef1e96e2d2d752)
Signed-off-by: Melody Olvera <molvera@codeaurora.org>
2021-02-01 08:20:44 +00:00
Masahiro Yamada
979f7488da UPSTREAM: modpost: rename merror() to error()
The log function names, warn(), merror(), fatal() are inconsistent.

Commit 2a11665945 ("kbuild: distinguish between errors and warnings
in modpost") intentionally chose merror() to avoid the conflict with
the library function error(). See man page of error(3).

But, we are already causing the conflict with warn() because it is also
a library function. See man page of warn(3). err() would be a problem
for the same reason.

The common technique to work around name conflicts is to use macros.

    #define error __error
    void __error(const char *fmt, ...)
    {
            <our own implementation>
    }

    #define warn __warn
    void __warn(const char *fmt, ...)
    {
            <our own implementation>
    }

In this way, we can implement our own warn() and error(), still we can
include <error.h> and <err.h> with no problem.

And, commit 93c95e526a ("modpost: rework and consolidate logging
interface") already did that.

Since the log functions are all macros, we can use error() without
causing "conflicting types" errors.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Bug: 176428324
Change-Id: Ief32b258e943026ad3f67a8c82c989129f8e654b
(cherry picked from commit bc72d723ec6b75c53e935e819682c3e67b83e9c1)
Signed-off-by: Melody Olvera <molvera@codeaurora.org>
2021-02-01 08:20:33 +00:00
Sami Tolvanen
beab453713 FROMLIST: scripts/mod: disable LTO for empty.c
With CONFIG_LTO_CLANG, clang generates LLVM IR instead of ELF object
files. As empty.o is used for probing target properties, disable LTO
for it to produce an object file instead.

Bug: 145210207
Change-Id: I8fa54c4c9b71f5d481a364b6eb10a4c34b2b71b7
Link: https://lore.kernel.org/lkml/20201211184633.3213045-12-samitolvanen@google.com/
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2020-12-16 08:56:34 -08:00
Sami Tolvanen
1f975cd7dd FROMLIST: modpost: lto: strip .lto from module names
With LTO, everything is compiled into LLVM bitcode, so we have to link
each module into native code before modpost. Kbuild uses the .lto.o
suffix for these files, which also ends up in module information. This
change strips the unnecessary .lto suffix from the module name.

Bug: 145210207
Change-Id: I25b97a586f273b1b8d1f153b71e567136b0016ec
Link: https://lore.kernel.org/lkml/20201211184633.3213045-11-samitolvanen@google.com/
Suggested-by: Bill Wendling <morbo@google.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2020-12-16 08:56:34 -08:00
Quentin Perret
479488f5bf ANDROID: modpost: Forbid double exports
In the context of GKI we are exporting quite a few internal kernel
symbols, some of which may be static functions (yes this is bad, but
technically it works). As such, we need to be careful about conflicts
and we really should not allow a symbol to be exported more than once.

To ensure this is the case, turn the modpost check 'fatal' to bail out
immediately when such a situation is detected.

Bug: 174214891
Signed-off-by: Quentin Perret <qperret@google.com>
Change-Id: I674c9c9c327849503e94d79654e6288411a830af
2020-11-27 14:50:45 +00:00
Quentin Perret
db78f3b149 FROMLIST: modpost: Make static exports fatal
Using EXPORT_SYMBOL*() on static functions is fundamentally wrong.
Modpost currently reports that as a warning, but clearly this is not a
pattern we should allow, and all in-tree occurences should have been
fixed by now. So, promote the warn() message to fatal() to make sure
this never happens again.

Bug: 174214891
Link: https://lore.kernel.org/lkml/20201124182420.2202514-1-qperret@google.com/
Signed-off-by: Quentin Perret <qperret@google.com>
Change-Id: Ic1382bfa24db556161cf1a184a4d44724d7849a1
2020-11-27 14:50:37 +00:00
Joe Perches
33def8498f treewide: Convert macro and uses of __section(foo) to __section("foo")
Use a more generic form for __section that requires quotes to avoid
complications with clang and gcc differences.

Remove the quote operator # from compiler_attributes.h __section macro.

Convert all unquoted __section(foo) uses to quoted __section("foo").
Also convert __attribute__((section("foo"))) uses to __section("foo")
even if the __attribute__ has multiple list entry forms.

Conversion done using the script at:

    https://lore.kernel.org/lkml/75393e5ddc272dc7403de74d645e6c6e0f4e70eb.camel@perches.com/2-convert_section.pl

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@gooogle.com>
Reviewed-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-25 14:51:49 -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
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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
faabed295c kbuild: introduce hostprogs-always-y and userprogs-always-y
To build host programs, you need to add the program names to 'hostprogs'
to use the necessary build rule, but it is not enough to build them
because there is no dependency.

There are two types of host programs: built as the prerequisite of
another (e.g. gen_crc32table in lib/Makefile), or always built when
Kbuild visits the Makefile (e.g. genksyms in scripts/genksyms/Makefile).

The latter is typical in Makefiles under scripts/, which contains host
programs globally used during the kernel build. To build them, you need
to add them to both 'hostprogs' and 'always-y'.

This commit adds hostprogs-always-y as a shorthand.

The same applies to user programs. net/bpfilter/Makefile builds
bpfilter_umh on demand, hence always-y is unneeded. In contrast,
programs under samples/ are added to both 'userprogs' and 'always-y'
so they are always built when Kbuild visits the Makefiles.

userprogs-always-y works as a shorthand.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
2020-08-10 01:32:59 +09:00
Linus Torvalds
1785d11612 Char/Misc driver patches for 5.9-rc1
Here is the large set of char and misc and other driver subsystem
 patches for 5.9-rc1.  Lots of new driver submissions in here, and
 cleanups and features for existing drivers.
 
 Highlights are:
 	- habanalabs driver updates
 	- coresight driver updates
 	- nvmem driver updates
 	- huge number of "W=1" build warning cleanups from Lee Jones
 	- dyndbg updates
 	- virtbox driver fixes and updates
 	- soundwire driver updates
 	- mei driver updates
 	- phy driver updates
 	- fpga driver updates
 	- lots of smaller individual misc/char driver cleanups and fixes
 
 Full details are in the shortlog.
 
 All of these have been in linux-next with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the large set of char and misc and other driver subsystem
  patches for 5.9-rc1. Lots of new driver submissions in here, and
  cleanups and features for existing drivers.

  Highlights are:
   - habanalabs driver updates
   - coresight driver updates
   - nvmem driver updates
   - huge number of "W=1" build warning cleanups from Lee Jones
   - dyndbg updates
   - virtbox driver fixes and updates
   - soundwire driver updates
   - mei driver updates
   - phy driver updates
   - fpga driver updates
   - lots of smaller individual misc/char driver cleanups and fixes

  Full details are in the shortlog.

  All of these have been in linux-next with no reported issues"

* tag 'char-misc-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (322 commits)
  habanalabs: remove unused but set variable 'ctx_asid'
  nvmem: qcom-spmi-sdam: Enable multiple devices
  dt-bindings: nvmem: SID: add binding for A100's SID controller
  nvmem: update Kconfig description
  nvmem: qfprom: Add fuse blowing support
  dt-bindings: nvmem: Add properties needed for blowing fuses
  dt-bindings: nvmem: qfprom: Convert to yaml
  nvmem: qfprom: use NVMEM_DEVID_AUTO for multiple instances
  nvmem: core: add support to auto devid
  nvmem: core: Add nvmem_cell_read_u8()
  nvmem: core: Grammar fixes for help text
  nvmem: sc27xx: add sc2730 efuse support
  nvmem: Enforce nvmem stride in the sysfs interface
  MAINTAINERS: Add git tree for NVMEM FRAMEWORK
  nvmem: sprd: Fix return value of sprd_efuse_probe()
  drivers: android: Fix the SPDX comment style
  drivers: android: Fix a variable declaration coding style issue
  drivers: android: Remove braces for a single statement if-else block
  drivers: android: Remove the use of else after return
  drivers: android: Fix a variable declaration coding style issue
  ...
2020-08-05 11:43:47 -07:00
Greg Kroah-Hartman
65a9bde6ed Linux 5.8-rc7
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Merge 5.8-rc7 into char-misc-next

This should resolve the merge/build issues reported when trying to
create linux-next.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-27 11:49:37 +02:00
Wolfram Sang
6020db504c modpost: explain why we can't use strsep
Mention why we open-code strsep, so it is clear that it is intentional.

Fixes: 736bb11898 ("modpost: remove use of non-standard strsep() in HOSTCC code")
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-07-27 13:38:38 +09:00
H. Nikolaus Schaller
736bb11898 modpost: remove use of non-standard strsep() in HOSTCC code
strsep() is neither standard C nor POSIX and used outside
the kernel code here. Using it here requires that the
build host supports it out of the box which is e.g.
not true for a Darwin build host and using a cross-compiler.
This leads to:

scripts/mod/modpost.c:145:2: warning: implicit declaration of function 'strsep' [-Wimplicit-function-declaration]
  return strsep(stringp, "\n");
  ^

and a segfault when running MODPOST.

See also: https://stackoverflow.com/a/7219504

So let's replace this by strchr() instead of using strsep().
It does not hurt kernel size or speed since this code is run
on the build host.

Fixes: ac5100f543 ("modpost: add read_text_file() and get_line() helpers")
Co-developed-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-07-07 11:21:00 +09:00
Pierre-Louis Bossart
b5924268d6 soundwire: extend SDW_SLAVE_ENTRY
The SoundWire 1.2 specification adds new capabilities that were not
present in previous version, such as the class ID.

To enable support for class drivers, and well as drivers that address
a specific version, all fields of the sdw_device_id structure need to
be exposed. For SoundWire 1.0 and 1.1 devices, a wildcard is used so
class and version information are ignored.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@linux.intel.com>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20200608205436.2402-4-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-06-30 21:26:17 +05:30
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.
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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
Linus Torvalds
e542e0dc3e Merge branch 'dmi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging
Pull dmi update from Jean Delvare.

* 'dmi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
  firmware/dmi: Report DMI Bios & EC firmware release
2020-06-06 11:30:00 -07:00
Masahiro Yamada
3b09efc4f0 modpost: change elf_info->size to size_t
Align with the mmap / munmap APIs.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:39:20 +09:00
Masahiro Yamada
4de7b62936 modpost: remove is_vmlinux() helper
Now that is_vmlinux() is called only in new_module(), we can inline
the function call.

modname is the basename with '.o' is stripped. No need to compare it
with 'vmlinux.o'.

vmlinux is always located at the current working directory. No need
to strip the directory path.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:39:20 +09:00
Masahiro Yamada
a82f794c41 modpost: strip .o from modname before calling new_module()
new_module() conditionally strips the .o because the modname has .o
suffix when it is called from read_symbols(), but no .o when it is
called from read_dump().

It is clearer to strip .o in read_symbols().

I also used flexible-array for mod->name.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:39:20 +09:00
Masahiro Yamada
858b937d28 modpost: set have_vmlinux in new_module()
Set have_vmlinux flag in a single place.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:39:20 +09:00
Masahiro Yamada
0b19d54cae modpost: remove mod->skip struct member
The meaning of 'skip' is obscure since it does not explain
"what to skip".

mod->skip is set when it is vmlinux or the module info came from
a dump file.

So, mod->skip is equivalent to (mod->is_vmlinux || mod->from_dump).

For the check in write_namespace_deps_files(), mod->is_vmlinux is
unneeded because the -d option is not passed in the first pass of
modpost.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:39:20 +09:00
Masahiro Yamada
5a438af9db modpost: add mod->is_vmlinux struct member
is_vmlinux() is called in several places to check whether the current
module is vmlinux or not.

It is faster and clearer to check mod->is_vmlinux flag.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:39:19 +09:00
Masahiro Yamada
1be5fa6c94 modpost: remove is_vmlinux() call in check_for_{gpl_usage,unused}()
check_exports() is never called for vmlinux because mod->skip is set
for vmlinux.

Hence, check_for_gpl_usage() and check_for_unused() are not called
for vmlinux, either. is_vmlinux() is always false here.

Remove the is_vmlinux() calls, and hard-code the ".ko" suffix.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:13 +09:00
Masahiro Yamada
3379576dd6 modpost: remove mod->is_dot_o struct member
Previously, there were two cases where mod->is_dot_o is unset:

[1] the executable 'vmlinux' in the second pass of modpost
[2] modules loaded by read_dump()

I think [1] was intended usage to distinguish 'vmlinux.o' and 'vmlinux'.
Now that modpost does not parse the executable 'vmlinux', this case
does not happen.

[2] is obscure, maybe a bug. Module.symver stores module paths without
extension. So, none of modules loaded by read_dump() has the .o suffix,
and new_module() unsets ->is_dot_o. Anyway, it is not a big deal because
handle_symbol() is not called for the case.

To sum up, all the parsed ELF files are .o files.

mod->is_dot_o is unneeded.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:13 +09:00
Masahiro Yamada
467b82d7ce modpost: remove -s option
The -s option was added by commit 8d8d8289df ("kbuild: do not do
section mismatch checks on vmlinux in 2nd pass").

Now that the second pass does not parse vmlinux, this option is
unneeded.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:13 +09:00
Masahiro Yamada
75893572d4 modpost: remove get_next_text() and make {grab,release_}file static
get_next_line() is no longer used. Remove.

grab_file() and release_file() are only used in modpost.c. Make them
static.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:13 +09:00
Masahiro Yamada
70f30cfe5b modpost: use read_text_file() and get_line() for reading text files
grab_file() mmaps a file, but it is not so efficient here because
get_next_line() copies every line to the temporary buffer anyway.

read_text_file() and get_line() are simpler. get_line() exploits the
library function strchr().

Going forward, the missing *.symvers or *.cmd is a fatal error.
This should not happen because scripts/Makefile.modpost guards the
-i option files with $(wildcard $(input-symdump)).

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:13 +09:00
Masahiro Yamada
7c8f5662c5 modpost: avoid false-positive file open error
One problem of grab_file() is that it cannot distinguish the following
two cases:

 - It cannot read the file (the file does not exist, or read permission
   is not set)

 - It can read the file, but the file size is zero

This is because grab_file() calls mmap(), which requires the mapped
length is greater than 0. Hence, grab_file() fails for both cases.

If an empty header file were included for checksum calculation, the
following warning would be printed:

  WARNING: modpost: could not open ...: Invalid argument

An empty file is a valid source file, so it should not fail.

Use read_text_file() instead. It can read a zero-length file.
Then, parse_file() will succeed with doing nothing.

Going forward, the first case (it cannot read the file) is a fatal
error. If the source file from which an object was compiled is missing,
something went wrong.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:13 +09:00
Masahiro Yamada
f531c1b5de modpost: fix potential mmap'ed file overrun in get_src_version()
I do not know how reliably this function works, but it looks dangerous
to me.

    strchr(sources, '\n');

... continues searching until it finds '\n' or it reaches the '\0'
terminator. In other words, 'sources' should be a null-terminated
string.

However, grab_file() just mmaps a file, so 'sources' is not terminated
with null byte. If the file does not contain '\n' at all, strchr() will
go beyond the mmap'ed memory.

Use read_text_file(), which loads the file content into a malloc'ed
buffer, appending null byte.

Here we are interested only in the first line of *.mod files. Use
get_line() helper to get the first line.

This also makes missing *.mod file a fatal error.

Commit 4be40e2223 ("kbuild: do not emit src version warning for
non-modules") ignored missing *.mod files.

I do not fully understand what that commit addressed, but commit
91341d4b2c ("kbuild: introduce new option to enhance section mismatch
analysis") introduced partial section checks by using modpost. built-in.o
was parsed by modpost. Even modules had a problem because *.mod files
were created after the modpost check.

Commit b7dca6dd1e ("kbuild: create *.mod with full directory path and
remove MODVERDIR") stopped doing that. Now that modpost is only invoked
after the directory descend, *.mod files should always exist at the
modpost stage.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:13 +09:00
Masahiro Yamada
ac5100f543 modpost: add read_text_file() and get_line() helpers
modpost uses grab_file() to open a file, but it is not suitable for
a text file because the mmap'ed file is not terminated by null byte.
Actually, I see some issues for the use of grab_file().

The new helper, read_text_file() loads the whole file content into a
malloc'ed buffer, and appends a null byte. Then, get_line() reads
each line.

To handle text files, I intend to replace as follows:

  grab_file()    -> read_text_file()
  get_new_line() -> get_line()

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:12 +09:00
Masahiro Yamada
4ddea2f8e8 modpost: do not call get_modinfo() for vmlinux(.o)
The three calls of get_modinfo() ("license", "import_ns", "version")
always return NULL for vmlinux(.o) because the built-in module info is
prefixed with __MODULE_INFO_PREFIX.

It is harmless to call get_modinfo(), but there is no point to search
for what apparently does not exist.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:12 +09:00
Masahiro Yamada
f693153519 modpost: drop RCS/CVS $Revision handling in MODULE_VERSION()
As far as I understood, this code gets rid of '$Revision$' or '$Revision:'
of CVS, RCS or whatever in MODULE_VERSION() tags.

Remove the primeval code.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:12 +09:00
Masahiro Yamada
7e8a323582 modpost: show warning if vmlinux is not found when processing modules
check_exports() does not print warnings about unresolved symbols if
vmlinux is missing because there would be too many.

This situation happens when you do 'make modules' from the clean
tree, or compile external modules against a kernel tree that has
not been completely built.

It is dangerous to not check unresolved symbols because you might be
building useless modules. At least it should be warned.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:12 +09:00
Masahiro Yamada
436b2ac603 modpost: invoke modpost only when input files are updated
Currently, the second pass of modpost is always invoked when you run
'make' or 'make modules' even if none of modules is changed.

Use if_changed to invoke it only when it is necessary.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:12 +09:00
Masahiro Yamada
e3fb4df7fe modpost: re-add -e to set external_module flag
Previously, the -i option had two functions; load a symbol dump file,
and set the external_module flag.

I want to assign a dedicate option for each of them.

Going forward, the -i is used to load a symbol dump file, and the -e
to set the external_module flag.

With this, we will be able to use -i for loading in-kernel symbols.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:12 +09:00
Masahiro Yamada
7924799ed2 modpost: rename ext_sym_list to dump_list
The -i option is used to include Modules.symver as well as files from
$(KBUILD_EXTRA_SYMBOLS).

Make the struct and variable names more generic.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:12 +09:00
Masahiro Yamada
ce2ddd6d6a modpost: allow to pass -i option multiple times to remove -e option
Now that there is no difference between -i and -e, they can be unified.

Make modpost accept the -i option multiple times, then remove -e.

I will reuse -e for a different purpose.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:38:12 +09:00
Masahiro Yamada
52c3416db0 modpost: track if the symbol origin is a dump file or ELF object
The meaning of sym->kernel is obscure; it is set for in-kernel symbols
loaded from Modules.symvers. This happens only when we are building
external modules, and it is used to determine whether to dump symbols
to $(KBUILD_EXTMOD)/Modules.symvers

It is clearer to remember whether the symbol or module came from a dump
file or ELF object.

This changes the KBUILD_EXTRA_SYMBOLS behavior. Previously, symbols
loaded from KBUILD_EXTRA_SYMBOLS are accumulated into the current
$(KBUILD_EXTMOD)/Modules.symvers

Going forward, they will be only used to check symbol references, but
not dumped into the current $(KBUILD_EXTMOD)/Modules.symvers. I believe
this makes more sense.

sym->vmlinux will have no user. Remove it too.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-06 23:36:55 +09:00
Erwan Velu
f5152f4ded firmware/dmi: Report DMI Bios & EC firmware release
Some vendors like HPe or Dell, encode the release version of their BIOS
in the "System BIOS {Major|Minor} Release" fields of Type 0.

This information is used to know which bios release actually runs.
It could be used for some quirks, debugging sessions or inventory tasks.

A typical output for a Dell system running the 65.27 bios is :
	[root@t1700 ~]# cat /sys/devices/virtual/dmi/id/bios_release
	65.27
	[root@t1700 ~]#

Servers that have a BMC encode the release version of their firmware in the
 "Embedded Controller Firmware {Major|Minor} Release" fields of Type 0.

This information is used to know which BMC release actually runs.
It could be used for some quirks, debugging sessions or inventory tasks.

A typical output for a Dell system running the 3.75 bmc release is :
    [root@t1700 ~]# cat /sys/devices/virtual/dmi/id/ec_firmware_release
    3.75
    [root@t1700 ~]#

Signed-off-by: Erwan Velu <e.velu@criteo.com>
Signed-off-by: Jean Delvare <jdelvare@suse.de>
2020-06-06 11:35:50 +02:00
Linus Torvalds
cb8e59cc87 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller:

 1) Allow setting bluetooth L2CAP modes via socket option, from Luiz
    Augusto von Dentz.

 2) Add GSO partial support to igc, from Sasha Neftin.

 3) Several cleanups and improvements to r8169 from Heiner Kallweit.

 4) Add IF_OPER_TESTING link state and use it when ethtool triggers a
    device self-test. From Andrew Lunn.

 5) Start moving away from custom driver versions, use the globally
    defined kernel version instead, from Leon Romanovsky.

 6) Support GRO vis gro_cells in DSA layer, from Alexander Lobakin.

 7) Allow hard IRQ deferral during NAPI, from Eric Dumazet.

 8) Add sriov and vf support to hinic, from Luo bin.

 9) Support Media Redundancy Protocol (MRP) in the bridging code, from
    Horatiu Vultur.

10) Support netmap in the nft_nat code, from Pablo Neira Ayuso.

11) Allow UDPv6 encapsulation of ESP in the ipsec code, from Sabrina
    Dubroca. Also add ipv6 support for espintcp.

12) Lots of ReST conversions of the networking documentation, from Mauro
    Carvalho Chehab.

13) Support configuration of ethtool rxnfc flows in bcmgenet driver,
    from Doug Berger.

14) Allow to dump cgroup id and filter by it in inet_diag code, from
    Dmitry Yakunin.

15) Add infrastructure to export netlink attribute policies to
    userspace, from Johannes Berg.

16) Several optimizations to sch_fq scheduler, from Eric Dumazet.

17) Fallback to the default qdisc if qdisc init fails because otherwise
    a packet scheduler init failure will make a device inoperative. From
    Jesper Dangaard Brouer.

18) Several RISCV bpf jit optimizations, from Luke Nelson.

19) Correct the return type of the ->ndo_start_xmit() method in several
    drivers, it's netdev_tx_t but many drivers were using
    'int'. From Yunjian Wang.

20) Add an ethtool interface for PHY master/slave config, from Oleksij
    Rempel.

21) Add BPF iterators, from Yonghang Song.

22) Add cable test infrastructure, including ethool interfaces, from
    Andrew Lunn. Marvell PHY driver is the first to support this
    facility.

23) Remove zero-length arrays all over, from Gustavo A. R. Silva.

24) Calculate and maintain an explicit frame size in XDP, from Jesper
    Dangaard Brouer.

25) Add CAP_BPF, from Alexei Starovoitov.

26) Support terse dumps in the packet scheduler, from Vlad Buslov.

27) Support XDP_TX bulking in dpaa2 driver, from Ioana Ciornei.

28) Add devm_register_netdev(), from Bartosz Golaszewski.

29) Minimize qdisc resets, from Cong Wang.

30) Get rid of kernel_getsockopt and kernel_setsockopt in order to
    eliminate set_fs/get_fs calls. From Christoph Hellwig.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2517 commits)
  selftests: net: ip_defrag: ignore EPERM
  net_failover: fixed rollback in net_failover_open()
  Revert "tipc: Fix potential tipc_aead refcnt leak in tipc_crypto_rcv"
  Revert "tipc: Fix potential tipc_node refcnt leak in tipc_rcv"
  vmxnet3: allow rx flow hash ops only when rss is enabled
  hinic: add set_channels ethtool_ops support
  selftests/bpf: Add a default $(CXX) value
  tools/bpf: Don't use $(COMPILE.c)
  bpf, selftests: Use bpf_probe_read_kernel
  s390/bpf: Use bcr 0,%0 as tail call nop filler
  s390/bpf: Maintain 8-byte stack alignment
  selftests/bpf: Fix verifier test
  selftests/bpf: Fix sample_cnt shared between two threads
  bpf, selftests: Adapt cls_redirect to call csum_level helper
  bpf: Add csum_level helper for fixing up csum levels
  bpf: Fix up bpf_skb_adjust_room helper's skb csum setting
  sfc: add missing annotation for efx_ef10_try_update_nic_stats_vf()
  crypto/chtls: IPv6 support for inline TLS
  Crypto/chcr: Fixes a coccinile check error
  Crypto/chcr: Fixes compilations warnings
  ...
2020-06-03 16:27:18 -07:00
Masahiro Yamada
2beee86899 modpost: load KBUILD_EXTRA_SYMBOLS files in order
Currently, modpost reads extra symbol dump files in the reverse order.
If '-e foo -e bar' is given, modpost reads bar, foo, in this order.

This is probably not a big deal, but there is no good reason to reverse
the order. Read files in the given order.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-03 13:22:18 +09:00
Masahiro Yamada
565587d8d5 modpost: refactor sech_name()
Use sym_get_data_by_offset() helper to get access to the .shstrtab
section data. No functional change is intended because
elf->sechdrs[elf->secindex_strings].sh_addr is 0 for both ET_REL
and ET_EXEC object types.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-29 03:08:49 +09:00
Masahiro Yamada
d2e4d05cf1 modpost: fix potential segmentation fault for addend_i386_rel()
This may not be a practical problem, but the second pass of ARCH=i386
modpost causes segmentation fault if the -s option is not passed.

    MODPOST 12 modules
  Segmentation fault (core dumped)
  make[2]: *** [scripts/Makefile.modpost:94: __modpost] Error 139
  make[1]: *** [Makefile:1339: modules] Error 2
  make[1]: *** Waiting for unfinished jobs....

The segmentation fault occurs when section_rel() is called for vmlinux,
which is untested in regular builds. The cause of the problem is
reloc_location() returning a wrong pointer for ET_EXEC object type.
In this case, you need to subtract sechdr->sh_addr, otherwise it would
get access beyond the mmap'ed memory.

Add sym_get_data_by_offset() helper to avoid code duplication.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-29 03:08:49 +09:00
Gustavo A. R. Silva
859c817501 modpost,fixdep: Replace zero-length array with flexible-array
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-26 00:03:16 +09:00