openwrt/staging/blogic.git
4 years agokbuild: do not pass $(KBUILD_CFLAGS) to scripts/mkcompile_h
Masahiro Yamada [Fri, 3 Apr 2020 21:24:59 +0000 (06:24 +0900)]
kbuild: do not pass $(KBUILD_CFLAGS) to scripts/mkcompile_h

scripts/mkcompile_h uses $(CC) only for getting the version string.

I suspected there was a specific reason why the additional flags were
needed, and dug the commit history. This code dates back to at least
2002 [1], but I could not get any more clue.

Just get rid of it.

[1]: https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/commit/?id=29f3df7eba8ddf91a55183f9967f76fbcc3ab742

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
4 years agoDocumentation/llvm: fix the name of llvm-size
Fangrui Song [Thu, 2 Apr 2020 17:38:42 +0000 (10:38 -0700)]
Documentation/llvm: fix the name of llvm-size

The tool is called llvm-size, not llvm-objsize.

Fixes: fcf1b6a35c16 ("Documentation/llvm: add documentation on building w/ Clang/LLVM")
Signed-off-by: Fangrui Song <maskray@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
4 years agokbuild: mkcompile_h: Include $LD version in /proc/version
Kees Cook [Thu, 2 Apr 2020 08:18:37 +0000 (01:18 -0700)]
kbuild: mkcompile_h: Include $LD version in /proc/version

When doing Clang builds of the kernel, it is possible to link with
either ld.bfd (binutils) or ld.lld (LLVM), but it is not possible to
discover this from a running kernel. Add the "$LD -v" output to
/proc/version.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Fangrui Song <maskray@google.com>
Reviewed-by: Sedat Dilek <sedat.dilek@gmail.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
4 years agokconfig: qconf: Fix a few alignment issues
Mauro Carvalho Chehab [Thu, 2 Apr 2020 09:28:03 +0000 (11:28 +0200)]
kconfig: qconf: Fix a few alignment issues

There are a few items with wrong alignments. Solve them.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
4 years agokconfig: qconf: remove some old bogus TODOs
Mauro Carvalho Chehab [Thu, 2 Apr 2020 09:28:02 +0000 (11:28 +0200)]
kconfig: qconf: remove some old bogus TODOs

The items described on those TODOs are already solved. So,
remove the comments.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
4 years agokconfig: qconf: fix support for the split view mode
Mauro Carvalho Chehab [Thu, 2 Apr 2020 09:28:01 +0000 (11:28 +0200)]
kconfig: qconf: fix support for the split view mode

At least on my tests (building against Qt5.13), it seems to
me that, since Kernel 3.14, the split view mode is broken.

Maybe it was not a top priority during the conversion time.

Anyway, this patch changes the logic in order to properly
support the split view mode and the single view mode.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
4 years agokconfig: qconf: fix the content of the main widget
Mauro Carvalho Chehab [Thu, 2 Apr 2020 09:28:00 +0000 (11:28 +0200)]
kconfig: qconf: fix the content of the main widget

The port to Qt5 tried to preserve the same way as it used
to work with Qt3 and Qt4. However, at least with newer
versions of Qt5 (5.13), this doesn't work properly.

Change the schema by adding a vertical layout, in order
for it to start working properly again.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
4 years agokconfig: qconf: Change title for the item window
Mauro Carvalho Chehab [Thu, 2 Apr 2020 09:27:59 +0000 (11:27 +0200)]
kconfig: qconf: Change title for the item window

Both main config window and the item window have "Option"
name. That sounds weird, and makes harder to debug issues
of a window appearing at the wrong place.

So, change the title to reflect the contents of each
window.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
4 years agokconfig: qconf: clean deprecated warnings
Mauro Carvalho Chehab [Thu, 2 Apr 2020 09:27:58 +0000 (11:27 +0200)]
kconfig: qconf: clean deprecated warnings

The recommended way to initialize a null string is with
QString(). This is there at least since Qt5.5, with is
when qconf was ported to Qt5.

Fix those warnings:

scripts/kconfig/qconf.cc: In member function ‘void ConfigItem::updateMenu()’:
scripts/kconfig/qconf.cc:158:31: warning: ‘QString::null’ is deprecated: use QString() [-Wdeprecated-declarations]
  158 |    setText(noColIdx, QString::null);
      |                               ^~~~
In file included from /usr/include/qt5/QtCore/qobject.h:47,
                 from /usr/include/qt5/QtWidgets/qwidget.h:45,
                 from /usr/include/qt5/QtWidgets/qmainwindow.h:44,
                 from /usr/include/qt5/QtWidgets/QMainWindow:1,
                 from scripts/kconfig/qconf.cc:9:

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
4 years agogcc-plugins: drop support for GCC <= 4.7
Masahiro Yamada [Sun, 29 Mar 2020 11:08:32 +0000 (20:08 +0900)]
gcc-plugins: drop support for GCC <= 4.7

Nobody was opposed to raising minimum GCC version to 4.8 [1]
So, we will drop GCC <= 4.7 support sooner or later.

We always use C++ compiler for building plugins for GCC >= 4.8.

This commit drops the plugin support for GCC <= 4.7 a bit earlier,
which allows us to dump lots of code.

[1] https://lkml.org/lkml/2020/1/23/545

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Kees Cook <keescook@chromium.org>
4 years agokbuild: Enable -Wtautological-compare
Nathan Chancellor [Thu, 26 Mar 2020 19:41:55 +0000 (12:41 -0700)]
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>
4 years agox86: update AS_* macros to binutils >=2.23, supporting ADX and AVX2
Jason A. Donenfeld [Thu, 26 Mar 2020 20:26:00 +0000 (14:26 -0600)]
x86: update AS_* macros to binutils >=2.23, supporting ADX and AVX2

Now that the kernel specifies binutils 2.23 as the minimum version, we
can remove ifdefs for AVX2 and ADX throughout.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
4 years agocrypto: x86 - clean up poly1305-x86_64-cryptogams.S by 'make clean'
Masahiro Yamada [Thu, 26 Mar 2020 08:01:04 +0000 (17:01 +0900)]
crypto: x86 - clean up poly1305-x86_64-cryptogams.S by 'make clean'

poly1305-x86_64-cryptogams.S is a generated file, so it should be
cleaned up by 'make clean'.

Assigning it to the variable 'targets' teaches Kbuild that it is a
generated file. However, this line is not evaluated when cleaning
because scripts/Makefile.clean does not include include/config/auto.conf.

Remove the ifneq-conditional, so this file is correctly cleaned up.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Ingo Molnar <mingo@kernel.org>
4 years agoDocumentation/changes: Raise minimum supported binutils version to 2.23
Borislav Petkov [Thu, 26 Mar 2020 08:01:02 +0000 (17:01 +0900)]
Documentation/changes: Raise minimum supported binutils version to 2.23

The currently minimum-supported binutils version 2.21 has the problem of
promoting symbols which are defined outside of a section into absolute.
According to Arvind:

  binutils-2.21 and -2.22. An x86-64 defconfig will fail with
          Invalid absolute R_X86_64_32S relocation: _etext
  and after fixing that one, with
          Invalid absolute R_X86_64_32S relocation: __end_of_kernel_reserve

Those two versions of binutils have a bug when it comes to handling
symbols defined outside of a section and binutils 2.23 has the proper
fix, see: https://sourceware.org/legacy-ml/binutils/2012-06/msg00155.html

Therefore, up to the fixed version directly, skipping the broken ones.

Currently shipping distros already have the fixed binutils version so
there should be no breakage resulting from this.

For more details about the whole thing, see the thread in Link.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200110202349.1881840-1-nivedita@alum.mit.edu
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
4 years agocrypto: curve25519 - do not pollute dispatcher based on assembler
Jason A. Donenfeld [Thu, 26 Mar 2020 08:01:01 +0000 (17:01 +0900)]
crypto: curve25519 - do not pollute dispatcher based on assembler

Since we're doing a static inline dispatch here, we normally branch
based on whether or not there's an arch implementation. That would have
been fine in general, except the crypto Makefile prior used to turn
things off -- despite the Kconfig -- resulting in us needing to also
hard code various assembler things into the dispatcher too. The horror!
Now that the assembler config options are done by Kconfig, we can get
rid of the inconsistency.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
4 years agocrypto: x86 - rework configuration based on Kconfig
Jason A. Donenfeld [Thu, 26 Mar 2020 08:01:00 +0000 (17:01 +0900)]
crypto: x86 - rework configuration based on Kconfig

Now that assembler capabilities are probed inside of Kconfig, we can set
up proper Kconfig-based dependencies. We also take this opportunity to
reorder the Makefile, so that items are grouped logically by primitive.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
4 years agox86: add comments about the binutils version to support code in as-instr
Masahiro Yamada [Thu, 26 Mar 2020 08:00:59 +0000 (17:00 +0900)]
x86: add comments about the binutils version to support code in as-instr

We raise the minimal supported binutils version from time to time.
The last bump was commit 1fb12b35e5ff ("kbuild: Raise the minimum
required binutils version to 2.21").

We have these as-instr tests because binutils 2.21 does not support
them.

When we bump the binutils version next time, this will be a good
hint to find out which one can be dropped.

As for the Clang/LLVM builds, we require very new LLVM version,
so the LLVM integrated assembler supports all of them.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
4 years agox86: probe assembler capabilities via kconfig instead of makefile
Jason A. Donenfeld [Thu, 26 Mar 2020 08:00:58 +0000 (17:00 +0900)]
x86: probe assembler capabilities via kconfig instead of makefile

Doing this probing inside of the Makefiles means we have a maze of
ifdefs inside the source code and child Makefiles that need to make
proper decisions on this too. Instead, we do it at Kconfig time, like
many other compiler and assembler options, which allows us to set up the
dependencies normally for full compilation units. In the process, the
ADX test changes to use %eax instead of %r10 so that it's valid in both
32-bit and 64-bit mode.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
4 years agodrm/i915: remove always-defined CONFIG_AS_MOVNTDQA
Masahiro Yamada [Thu, 26 Mar 2020 08:00:57 +0000 (17:00 +0900)]
drm/i915: remove always-defined CONFIG_AS_MOVNTDQA

CONFIG_AS_MOVNTDQA was introduced by commit 0b1de5d58e19 ("drm/i915:
Use SSE4.1 movntdqa to accelerate reads from WC memory").

We raise the minimal supported binutils version from time to time.
The last bump was commit 1fb12b35e5ff ("kbuild: Raise the minimum
required binutils version to 2.21").

I confirmed the code in $(call as-instr,...) can be assembled by the
binutils 2.21 assembler and also by LLVM integrated assembler.

Remove CONFIG_AS_MOVNTDQA, which is always defined.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Jani Nikula <jani.nikula@intel.com>
4 years agox86: remove always-defined CONFIG_AS_AVX
Masahiro Yamada [Thu, 26 Mar 2020 08:00:55 +0000 (17:00 +0900)]
x86: remove always-defined CONFIG_AS_AVX

CONFIG_AS_AVX was introduced by commit ea4d26ae24e5 ("raid5: add AVX
optimized RAID5 checksumming").

We raise the minimal supported binutils version from time to time.
The last bump was commit 1fb12b35e5ff ("kbuild: Raise the minimum
required binutils version to 2.21").

I confirmed the code in $(call as-instr,...) can be assembled by the
binutils 2.21 assembler and also by LLVM integrated assembler.

Remove CONFIG_AS_AVX, which is always defined.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
4 years agox86: remove always-defined CONFIG_AS_SSSE3
Masahiro Yamada [Thu, 26 Mar 2020 08:00:54 +0000 (17:00 +0900)]
x86: remove always-defined CONFIG_AS_SSSE3

CONFIG_AS_SSSE3 was introduced by commit 75aaf4c3e6a4 ("x86/raid6:
correctly check for assembler capabilities").

We raise the minimal supported binutils version from time to time.
The last bump was commit 1fb12b35e5ff ("kbuild: Raise the minimum
required binutils version to 2.21").

I confirmed the code in $(call as-instr,...) can be assembled by the
binutils 2.21 assembler and also by LLVM integrated assembler.

Remove CONFIG_AS_SSSE3, which is always defined.

I added ifdef CONFIG_X86 to lib/raid6/algos.c to avoid link errors
on non-x86 architectures.

lib/raid6/algos.c is built not only for the kernel but also for
testing the library code from userspace. I added -DCONFIG_X86 to
lib/raid6/test/Makefile to cator to this usecase.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
4 years agox86: remove always-defined CONFIG_AS_CFI_SECTIONS
Masahiro Yamada [Thu, 26 Mar 2020 08:00:53 +0000 (17:00 +0900)]
x86: remove always-defined CONFIG_AS_CFI_SECTIONS

CONFIG_AS_CFI_SECTIONS was introduced by commit 9e565292270a ("x86:
Use .cfi_sections for assembly code").

We raise the minimal supported binutils version from time to time.
The last bump was commit 1fb12b35e5ff ("kbuild: Raise the minimum
required binutils version to 2.21").

I confirmed the code in $(call as-instr,...) can be assembled by the
binutils 2.21 assembler and also by LLVM integrated assembler.

Remove CONFIG_AS_CFI_SECTIONS, which is always defined.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
4 years agox86: remove unneeded (CONFIG_AS_)CFI_SIGNAL_FRAME
Masahiro Yamada [Thu, 26 Mar 2020 08:00:52 +0000 (17:00 +0900)]
x86: remove unneeded (CONFIG_AS_)CFI_SIGNAL_FRAME

Commit 131484c8da97 ("x86/debug: Remove perpetually broken,
unmaintainable dwarf annotations") removes all the users of
CFI_SIGNAL_FRAME.

Remove the CFI_SIGNAL_FRAME and CONFIG_AS_CFI_SIGNAL_FRAME.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
4 years agox86: remove always-defined CONFIG_AS_CFI
Masahiro Yamada [Thu, 26 Mar 2020 08:00:51 +0000 (17:00 +0900)]
x86: remove always-defined CONFIG_AS_CFI

CONFIG_AS_CFI was introduced by commit e2414910f212 ("[PATCH] x86:
Detect CFI support in the assembler at runtime"), and extended by
commit f0f12d85af85 ("x86_64: Check for .cfi_rel_offset in CFI probe").

We raise the minimal supported binutils version from time to time.
The last bump was commit 1fb12b35e5ff ("kbuild: Raise the minimum
required binutils version to 2.21").

I confirmed the code in $(call as-instr,...) can be assembled by the
binutils 2.21 assembler and also by LLVM integrated assembler.

Remove CONFIG_AS_CFI, which is always defined.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
4 years agox86: remove unneeded defined(__ASSEMBLY__) check from asm/dwarf2.h
Masahiro Yamada [Thu, 26 Mar 2020 08:00:50 +0000 (17:00 +0900)]
x86: remove unneeded defined(__ASSEMBLY__) check from asm/dwarf2.h

This header file has the following check at the top:

  #ifndef __ASSEMBLY__
  #warning "asm/dwarf2.h should be only included in pure assembly files"
  #endif

So, we expect defined(__ASSEMBLY__) is always true.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
4 years agolib/raid6/test: fix build on distros whose /bin/sh is not bash
Masahiro Yamada [Thu, 26 Mar 2020 08:00:49 +0000 (17:00 +0900)]
lib/raid6/test: fix build on distros whose /bin/sh is not bash

You can build a user-space test program for the raid6 library code,
like this:

  $ cd lib/raid6/test
  $ make

The command in $(shell ...) function is evaluated by /bin/sh by default.
(or, you can specify the shell by passing SHELL=<shell> from command line)

Currently '>&/dev/null' is used to sink both stdout and stderr. Because
this code is bash-ism, it only works when /bin/sh is a symbolic link to
bash (this is the case on RHEL etc.)

This does not work on Ubuntu where /bin/sh is a symbolic link to dash.

I see lots of

  /bin/sh: 1: Syntax error: Bad fd number

and

  warning "your version of binutils lacks ... support"

Replace it with portable '>/dev/null 2>&1'.

Fixes: 4f8c55c5ad49 ("lib/raid6: build proper files on corresponding arch")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
4 years agosh: remove unneeded uapi asm-generic wrappers
Masahiro Yamada [Tue, 23 Jul 2019 11:30:36 +0000 (20:30 +0900)]
sh: remove unneeded uapi asm-generic wrappers

These are listed in include/uapi/asm-generic/Kbuild, so Kbuild will
automatically generate them.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
4 years agoh8300: move definition of __kernel_size_t etc. to posix_types.h
Masahiro Yamada [Tue, 23 Jul 2019 10:21:06 +0000 (19:21 +0900)]
h8300: move definition of __kernel_size_t etc. to posix_types.h

These types should be defined in posix_types.h, not in bitsperlong.h .

With these defines moved, h8300-specific bitsperlong.h is no longer
needed since Kbuild will automatically create a wrapper of
include/uapi/asm-generic/bitsperlong.h

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
4 years agosh: use __builtin_constant_p() directly instead of IS_IMMEDIATE()
Masahiro Yamada [Tue, 23 Jul 2019 07:49:43 +0000 (16:49 +0900)]
sh: use __builtin_constant_p() directly instead of IS_IMMEDIATE()

__builtin_constant_p(nr) is used everywhere now. It does not make
much sense to define IS_IMMEDIATE() as its alias.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
4 years agoMerge tag 'drm-next-2020-04-08' of git://anongit.freedesktop.org/drm/drm
Linus Torvalds [Wed, 8 Apr 2020 03:24:34 +0000 (20:24 -0700)]
Merge tag 'drm-next-2020-04-08' of git://anongit.freedesktop.org/drm/drm

Pull drm fixes from Dave Airlie:
 "This is a set of fixes that have queued up, I think I might have
  another pull with some more before rc1 but I'd like to dequeue what I
  have now just in case Easter is more eggciting that expected.

  The main thing in here is a fix for a longstanding nouveau power
  management issues on certain laptops, it should help runtime
  suspend/resume for a lot of people.

  There is also a reverted patch for some drm_mm behaviour in atomic
  contexts.

  Summary:

  core:
   - revert drm_mm atomic patch
   - dt binding fixes

  fbcon:
   - null ptr error fix

  i915:
   - GVT fixes

  nouveau:
   - runpm fix
   - svm fixes

  amdgpu:
   - HDCP fixes
   - gfx10 fix
   - Misc display fixes
   - BACO fixes

  amdkfd:
   - Fix memory leak

  vboxvideo:
   - remove conflicting fbs

  vc4:
   - mode validation fix

  xen:
   - fix PTR_ERR usage"

* tag 'drm-next-2020-04-08' of git://anongit.freedesktop.org/drm/drm: (41 commits)
  drm/nouveau/kms/nv50-: wait for FIFO space on PIO channels
  drm/nouveau/nvif: protect waits against GPU falling off the bus
  drm/nouveau/nvif: access PTIMER through usermode class, if available
  drm/nouveau/gr/gp107,gp108: implement workaround for HW hanging during init
  drm/nouveau: workaround runpm fail by disabling PCI power management on certain intel bridges
  drm/nouveau/svm: remove useless SVM range check
  drm/nouveau/svm: check for SVM initialized before migrating
  drm/nouveau/svm: fix vma range check for migration
  drm/nouveau: remove checks for return value of debugfs functions
  drm/nouveau/ttm: evict other IO mappings when running out of BAR1 space
  drm/amdkfd: kfree the wrong pointer
  drm/amd/display: increase HDCP authentication delay
  drm/amd/display: Correctly cancel future watchdog and callback events
  drm/amd/display: Don't try hdcp1.4 when content_type is set to type1
  drm/amd/powerplay: move the ASIC specific nbio operation out of smu_v11_0.c
  drm/amd/powerplay: drop redundant BIF doorbell interrupt operations
  drm/amd/display: Fix dcn21 num_states
  drm/amd/display: Enable BT2020 in COLOR_ENCODING property
  drm/amd/display: LFC not working on 2.0x range monitors (v2)
  drm/amd/display: Support plane level CTM
  ...

4 years agoMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Linus Torvalds [Wed, 8 Apr 2020 03:20:12 +0000 (20:20 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/dtor/input

Pull input updates from Dmitry Torokhov:
 "An update to the Goodix touchscreen driver to enable it work properly
  on various Bay Trail and Cherry Trail devices, and a few other
  assorted changes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (26 commits)
  Input: update SPDX tag for input-event-codes.h
  Input: i8042 - add Acer Aspire 5738z to nomux list
  Input: goodix - fix compilation when ACPI support is disabled
  dt-bindings: touchscreen: Convert edt-ft5x06 to json-schema
  Input: of_touchscreen - explicitly choose axis
  Input: goodix - support gt9147 touchpanel
  dt-bindings: touchscreen: goodix: support of gt9147
  Input: goodix - add support for Goodix GT917S
  Input: goodix - use string-based chip ID
  dt-bindings: input: touchscreen: add compatible string for Goodix GT917S
  Input: goodix - add support for more then one touch-key
  Input: goodix - fix spurious key release events
  Input: goodix - try to reset the controller if the i2c-test fails
  Input: goodix - restore config on resume if necessary
  Input: goodix - make goodix_send_cfg() take a raw buffer as argument
  Input: goodix - add minimum firmware size check
  Input: goodix - save a copy of the config from goodix_read_config()
  Input: goodix - move defines to above struct goodix_ts_data declaration
  Input: goodix - add support for controlling the IRQ pin through ACPI methods
  Input: goodix - add support for getting IRQ + reset GPIOs on Bay Trail devices
  ...

4 years agoMerge tag 'thermal-v5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thermal...
Linus Torvalds [Wed, 8 Apr 2020 03:00:16 +0000 (20:00 -0700)]
Merge tag 'thermal-v5.7-rc1' of git://git./linux/kernel/git/thermal/linux

Pull thermal updates from Daniel Lezcano:

 - Convert tsens configuration DT binding to yaml (Rajeshwari)

 - Add interrupt support on the rcar sensor (Niklas Söderlund)

 - Add a new Spreadtrum thermal driver (Baolin Wang)

 - Add thermal binding for the fsl scu board, a new API to retrieve the
   sensor id bound to the thermal zone and i.MX system controller sensor
   (Anson Huang))

 - Remove warning log when a deferred probe is requested on Exynos
   (Marek Szyprowski)

 - Add the thermal monitoring unit support for imx8mm with its DT
   bindings (Anson Huang)

 - Rephrase the Kconfig text for clarity (Linus Walleij)

 - Use the gpio descriptor for the ti-soc-thermal (Linus Walleij)

 - Align msg structure to 4 bytes for i.MX SC, fix the Kconfig
   dependency, add the __may_be unused annotation for PM functions and
   the COMPILE_TEST option for imx8mm (Anson Huang)

 - Fix a dependency on regmap in Kconfig for qoriq (Yuantian Tang)

 - Add DT binding and support for the rcar gen3 r8a77961 and improve the
   error path on the rcar init function (Niklas Söderlund)

 - Cleanup and improvements for the tsens Qcom sensor (Amit Kucheria)

 - Improve code by removing lock and caching values in the rcar thermal
   sensor (Niklas Söderlund)

 - Cleanup in the qoriq drivers and add a call to
   imx_thermal_unregister_legacy_cooling in the removal function (Anson
   Huang)

 - Remove redundant 'maxItems' in tsens and sprd DT bindings (Rob
   Herring)

 - Change the thermal DT bindings by making the cooling-maps optional
   (Yuantian Tang)

 - Add Tiger Lake support (Sumeet Pawnikar)

 - Use scnprintf() for avoiding potential buffer overflow (Takashi Iwai)

 - Make pkg_temp_lock a raw_spinlock_t(Clark Williams)

 - Fix incorrect data types by changing them to signed on i.MX SC (Anson
   Huang)

 - Replace zero-length array with flexible-array member (Gustavo A. R.
   Silva)

 - Add support for i.MX8MP in the driver and in the DT bindings (Anson
   Huang)

 - Fix return value of the cpufreq_set_cur_state() function (Willy
   Wolff)

 - Remove abusing and scary WARN_ON in the cpufreq cooling device
   (Daniel Lezcano)

 - Fix build warning of incorrect argument type reported by sparse on
   imx8mm (Anson Huang)

 - Fix stub for the devfreq cooling device (Martin Blumenstingl)

 - Fix cpu idle cooling documentation (Sergey Vidishev)

* tag 'thermal-v5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thermal/linux: (52 commits)
  Documentation: cpu-idle-cooling: Fix diagram for 33% duty cycle
  thermal: devfreq_cooling: inline all stubs for CONFIG_DEVFREQ_THERMAL=n
  thermal: imx8mm: Fix build warning of incorrect argument type
  thermal/drivers/cpufreq_cooling: Remove abusing WARN_ON
  thermal/drivers/cpufreq_cooling: Fix return of cpufreq_set_cur_state
  thermal: imx8mm: Add i.MX8MP support
  dt-bindings: thermal: imx8mm-thermal: Add support for i.MX8MP
  thermal: qcom: tsens.h: Replace zero-length array with flexible-array member
  thermal: imx_sc_thermal: Fix incorrect data type
  thermal: int340x_thermal: Use scnprintf() for avoiding potential buffer overflow
  thermal: int340x: processor_thermal: Add Tiger Lake support
  thermal/x86_pkg_temp: Make pkg_temp_lock a raw_spinlock_t
  dt-bindings: thermal: make cooling-maps property optional
  dt-bindings: thermal: qcom-tsens: Remove redundant 'maxItems'
  dt-bindings: thermal: sprd: Remove redundant 'maxItems'
  thermal: imx: Calling imx_thermal_unregister_legacy_cooling() in .remove
  thermal: qoriq: Sort includes alphabetically
  thermal: qoriq: Use devm_add_action_or_reset() to handle all cleanups
  thermal: rcar_thermal: Remove lock in rcar_thermal_get_current_temp()
  thermal: rcar_thermal: Do not store ctemp in rcar_thermal_priv
  ...

4 years agoMerge tag 'mfd-next-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd
Linus Torvalds [Wed, 8 Apr 2020 02:48:52 +0000 (19:48 -0700)]
Merge tag 'mfd-next-5.7' of git://git./linux/kernel/git/lee/mfd

Pull mfd updates from Lee Jones:
 "New Drivers:
   - Add support for IQS620A/621/622/624/625 Azoteq IQS62X Sensors

  New Device Support:
   - Add support for ADC, IRQ, Regulator, RTC and WDT to Ricoh RN5T618 PMIC
   - Add support for Comet Lake to Intel LPSS

  New Functionality:
   - Add support for Charger Detection to Spreadtrum SC27xx PMICs
   - Add support for Interrupt Polarity to Dialog Semi DA9062/61 PMIC
   - Add ACPI enumeration support to Diolan DLN2 USB Adaptor

  Fix-ups:
   - Device Tree; iqs62x, rn5t618, cros_ec_dev, stm32-lptimer, rohm,bd71837, rohm,bd71847
   - I2C registration; rn5t618
   - Kconfig; MFD_CPCAP, AB8500_CORE, MFD_WM8994, MFD_WM97xx, MFD_STPMIC1
   - Use flexible-array members; omap-usb-tll, qcom-pm8xxx
   - Remove unnecessary casts; omap-usb-host, omap-usb-tll
   - Power (suspend/resume/poweroff) enhancements; rk808
   - Improve error/sanity checking; dln2
   - Use snprintf(); aat2870-core

  Bug Fixes:
   - Fix PCI IDs in intel-lpss-pci"

* tag 'mfd-next-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd: (33 commits)
  mfd: intel-lpss: Fix Intel Elkhart Lake LPSS I2C input clock
  mfd: aat2870: Use scnprintf() for avoiding potential buffer overflow
  mfd: dln2: Allow to be enumerated via ACPI
  mfd: da9062: Add support for interrupt polarity defined in device tree
  dt-bindings: bd718x7: Yamlify and add BD71850
  mfd: dln2: Fix sanity checking for endpoints
  mfd: intel-lpss: Add Intel Comet Lake PCH-V PCI IDs
  mfd: sc27xx: Add USB charger type detection support
  dt-bindings: mfd: Document STM32 low power timer bindings
  mfd: rk808: Convert RK805 to shutdown/suspend hooks
  mfd: rk808: Reduce shutdown duplication
  mfd: rk808: Stop using syscore ops
  mfd: rk808: Ensure suspend/resume hooks always work
  mfd: rk808: Always use poweroff when requested
  mfd: omap: Remove useless cast for driver.name
  mfd: Kconfig: Fix some misspelling of the word functionality
  mfd: pm8xxx: Replace zero-length array with flexible-array member
  mfd: omap-usb-tll: Replace zero-length array with flexible-array member
  mfd: cpcap: Fix compile if MFD_CORE is not selected
  mfd: cros_ec: Check DT node for usbpd-notify add
  ...

4 years agoMerge tag 'backlight-next-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/lee...
Linus Torvalds [Wed, 8 Apr 2020 02:44:52 +0000 (19:44 -0700)]
Merge tag 'backlight-next-5.7' of git://git./linux/kernel/git/lee/backlight

Pull backlight updates from Lee Jones:
 "Switch pwm_bl and corgi_lcd drivers to use GPIO descriptors"

* tag 'backlight-next-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
  backlight: corgi: Convert to use GPIO descriptors
  backlight: pwm_bl: Switch to full GPIO descriptor

4 years agoMerge tag 'leds-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/pavel/linux...
Linus Torvalds [Wed, 8 Apr 2020 02:41:12 +0000 (19:41 -0700)]
Merge tag 'leds-5.7-rc1' of git://git./linux/kernel/git/pavel/linux-leds

Pull LED updates from Pavel Machek:
 "One new driver, some driver changes, and some late minute cleanups --
  but those are just whitespace so should be okay.

  There are some major changes being prepared (multicolor, triggers) so
  the next release likely will be more interesting"

* tag 'leds-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/pavel/linux-leds:
  leds: core: Fix warning message when init_data
  leds: make functions easier to understand
  leds: sort Makefile entries
  leds: old enums are not really applicable to new code
  leds: ip30: label power LED as such
  leds: lm3532: make bitfield 'enabled' unsigned
  leds: leds-pwm: Replace zero-length array with flexible-array member
  leds: leds-is31fl32xx: Replace zero-length array with flexible-array member
  leds: pwm: remove useless pwm_period_ns
  leds: pwm: remove header
  leds: pwm: convert to atomic PWM API
  leds: pwm: simplify if condition
  leds: add SGI IP30 led support
  leds: lm3697: fix spelling mistake "To" -> "Too"
  leds: leds-bd2802: remove set but not used variable 'pdata'
  leds: ns2: Convert to GPIO descriptors
  leds: ns2: Absorb platform data

4 years agomm/gup: Mark lock taken only after a successful retake
Peter Xu [Wed, 8 Apr 2020 01:40:10 +0000 (21:40 -0400)]
mm/gup: Mark lock taken only after a successful retake

It's definitely incorrect to mark the lock as taken even if
down_read_killable() failed.

This wass overlooked when we switched from down_read() to
down_read_killable() because down_read() won't fail while
down_read_killable() could.

Fixes: 71335f37c5e8 ("mm/gup: allow to react to fatal signals")
Reported-by: syzbot+a8c70b7f3579fc0587dc@syzkaller.appspotmail.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agomm/mempolicy: Allow lookup_node() to handle fatal signal
Peter Xu [Wed, 8 Apr 2020 01:40:09 +0000 (21:40 -0400)]
mm/mempolicy: Allow lookup_node() to handle fatal signal

lookup_node() uses gup to pin the page and get node information.  It
checks against ret>=0 assuming the page will be filled in.  However it's
also possible that gup will return zero, for example, when the thread is
quickly killed with a fatal signal.  Teach lookup_node() to gracefully
return an error -EFAULT if it happens.

Meanwhile, initialize "page" to NULL to avoid potential risk of
exploiting the pointer.

Fixes: 4426e945df58 ("mm/gup: allow VM_FAULT_RETRY for multiple times")
Reported-by: syzbot+693dc11fcb53120b5559@syzkaller.appspotmail.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoMerge tag 'amd-drm-next-5.7-2020-04-01' of git://people.freedesktop.org/~agd5f/linux...
Dave Airlie [Tue, 7 Apr 2020 23:34:26 +0000 (09:34 +1000)]
Merge tag 'amd-drm-next-5.7-2020-04-01' of git://people.freedesktop.org/~agd5f/linux into drm-next

amd-drm-next-5.7-2020-04-01:

amdgpu:
- HDCP fixes
- gfx10 fix
- Misc display fixes
- BACO fixes

amdkfd:
- Fix memory leak

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Alex Deucher <alexdeucher@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200401194619.4217-1-alexander.deucher@amd.com
4 years agoMerge branch 'linux-5.7' of git://github.com/skeggsb/linux into drm-next
Dave Airlie [Tue, 7 Apr 2020 23:16:14 +0000 (09:16 +1000)]
Merge branch 'linux-5.7' of git://github.com/skeggsb/linux into drm-next

A couple of misc fixes/workarounds for some issues that are causing a
lot of pain for people.

Of most interest are the PCI power management and GR init WARs, which
effect a rather significant number of laptop systems that are in use
today.

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Ben Skeggs <skeggsb@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/
4 years agoMerge tag 'drm-misc-next-fixes-2020-04-04' of git://anongit.freedesktop.org/drm/drm...
Dave Airlie [Tue, 7 Apr 2020 23:14:21 +0000 (09:14 +1000)]
Merge tag 'drm-misc-next-fixes-2020-04-04' of git://anongit.freedesktop.org/drm/drm-misc into drm-next

A bunch of fixes to avoid null pointer dereference in fbcon, fix a return
in xen, some DT bindings fixes, a vc4 issue with 1920x1200 mode validation,
and a conflicting framebuffer in vboxvideo.

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200404090057.a3m7uw6tavwtcyon@gilmour.lan
4 years agoMerge tag 'drm-intel-next-fixes-2020-04-02' of git://anongit.freedesktop.org/drm...
Dave Airlie [Tue, 7 Apr 2020 23:12:56 +0000 (09:12 +1000)]
Merge tag 'drm-intel-next-fixes-2020-04-02' of git://anongit.freedesktop.org/drm/drm-intel into drm-next

Only gvt fixes on this round:

- Fix non-privilege access warning (Tina)
- Fix display port type (Tina)
- BDW cmd parser missed SWTESS_BASE_ADDRESS (Yan)
- Bypass length check of LRI (Yan)
- Fix one klocwork warning (Tina)

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200402213026.GA1141017@intel.com
4 years agoMerge branch 'akpm' (patches from Andrew)
Linus Torvalds [Tue, 7 Apr 2020 21:11:54 +0000 (14:11 -0700)]
Merge branch 'akpm' (patches from Andrew)

Merge more updates from Andrew Morton:

 - a lot more of MM, quite a bit more yet to come: (memcg, pagemap,
   vmalloc, pagealloc, migration, thp, ksm, madvise, virtio,
   userfaultfd, memory-hotplug, shmem, rmap, zswap, zsmalloc, cleanups)

 - various other subsystems (procfs, misc, MAINTAINERS, bitops, lib,
   checkpatch, epoll, binfmt, kallsyms, reiserfs, kmod, gcov, kconfig,
   ubsan, fault-injection, ipc)

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (158 commits)
  ipc/shm.c: make compat_ksys_shmctl() static
  ipc/mqueue.c: fix a brace coding style issue
  lib/Kconfig.debug: fix a typo "capabilitiy" -> "capability"
  ubsan: include bug type in report header
  kasan: unset panic_on_warn before calling panic()
  ubsan: check panic_on_warn
  drivers/misc/lkdtm/bugs.c: add arithmetic overflow and array bounds checks
  ubsan: split "bounds" checker from other options
  ubsan: add trap instrumentation option
  init/Kconfig: clean up ANON_INODES and old IO schedulers options
  kernel/gcov/fs.c: replace zero-length array with flexible-array member
  gcov: gcc_3_4: replace zero-length array with flexible-array member
  gcov: gcc_4_7: replace zero-length array with flexible-array member
  kernel/kmod.c: fix a typo "assuems" -> "assumes"
  reiserfs: clean up several indentation issues
  kallsyms: unexport kallsyms_lookup_name() and kallsyms_on_each_symbol()
  samples/hw_breakpoint: drop use of kallsyms_lookup_name()
  samples/hw_breakpoint: drop HW_BREAKPOINT_R when reporting writes
  fs/binfmt_elf.c: don't free interpreter's ELF pheaders on common path
  fs/binfmt_elf.c: allocate less for static executable
  ...

4 years agoMerge tag 'nfs-for-5.7-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Linus Torvalds [Tue, 7 Apr 2020 20:51:39 +0000 (13:51 -0700)]
Merge tag 'nfs-for-5.7-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client updates from Trond Myklebust:
 "Highlights include:

  Stable fixes:
   - Fix a page leak in nfs_destroy_unlinked_subrequests()

   - Fix use-after-free issues in nfs_pageio_add_request()

   - Fix new mount code constant_table array definitions

   - finish_automount() requires us to hold 2 refs to the mount record

  Features:
   - Improve the accuracy of telldir/seekdir by using 64-bit cookies
     when possible.

   - Allow one RDMA active connection and several zombie connections to
     prevent blocking if the remote server is unresponsive.

   - Limit the size of the NFS access cache by default

   - Reduce the number of references to credentials that are taken by
     NFS

   - pNFS files and flexfiles drivers now support per-layout segment
     COMMIT lists.

   - Enable partial-file layout segments in the pNFS/flexfiles driver.

   - Add support for CB_RECALL_ANY to the pNFS flexfiles layout type

   - pNFS/flexfiles Report NFS4ERR_DELAY and NFS4ERR_GRACE errors from
     the DS using the layouterror mechanism.

  Bugfixes and cleanups:
   - SUNRPC: Fix krb5p regressions

   - Don't specify NFS version in "UDP not supported" error

   - nfsroot: set tcp as the default transport protocol

   - pnfs: Return valid stateids in nfs_layout_find_inode_by_stateid()

   - alloc_nfs_open_context() must use the file cred when available

   - Fix locking when dereferencing the delegation cred

   - Fix memory leaks in O_DIRECT when nfs_get_lock_context() fails

   - Various clean ups of the NFS O_DIRECT commit code

   - Clean up RDMA connect/disconnect

   - Replace zero-length arrays with C99-style flexible arrays"

* tag 'nfs-for-5.7-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (86 commits)
  NFS: Clean up process of marking inode stale.
  SUNRPC: Don't start a timer on an already queued rpc task
  NFS/pnfs: Reference the layout cred in pnfs_prepare_layoutreturn()
  NFS/pnfs: Fix dereference of layout cred in pnfs_layoutcommit_inode()
  NFS: Beware when dereferencing the delegation cred
  NFS: Add a module parameter to set nfs_mountpoint_expiry_timeout
  NFS: finish_automount() requires us to hold 2 refs to the mount record
  NFS: Fix a few constant_table array definitions
  NFS: Try to join page groups before an O_DIRECT retransmission
  NFS: Refactor nfs_lock_and_join_requests()
  NFS: Reverse the submission order of requests in __nfs_pageio_add_request()
  NFS: Clean up nfs_lock_and_join_requests()
  NFS: Remove the redundant function nfs_pgio_has_mirroring()
  NFS: Fix memory leaks in nfs_pageio_stop_mirroring()
  NFS: Fix a request reference leak in nfs_direct_write_clear_reqs()
  NFS: Fix use-after-free issues in nfs_pageio_add_request()
  NFS: Fix races nfs_page_group_destroy() vs nfs_destroy_unlinked_subrequests()
  NFS: Fix a page leak in nfs_destroy_unlinked_subrequests()
  NFS: Remove unused FLUSH_SYNC support in nfs_initiate_pgio()
  pNFS/flexfiles: Specify the layout segment range in LAYOUTGET
  ...

4 years agoMerge tag 'f2fs-for-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk...
Linus Torvalds [Tue, 7 Apr 2020 20:48:26 +0000 (13:48 -0700)]
Merge tag 'f2fs-for-5.7-rc1' of git://git./linux/kernel/git/jaegeuk/f2fs

Pull f2fs updates from Jaegeuk Kim:
 "In this round, we've mainly focused on fixing bugs and addressing
  issues in recently introduced compression support.

  Enhancement:
   - add zstd support, and set LZ4 by default
   - add ioctl() to show # of compressed blocks
   - show mount time in debugfs
   - replace rwsem with spinlock
   - avoid lock contention in DIO reads

  Some major bug fixes wrt compression:
   - compressed block count
   - memory access and leak
   - remove obsolete fields
   - flag controls

  Other bug fixes and clean ups:
   - fix overflow when handling .flags in inode_info
   - fix SPO issue during resize FS flow
   - fix compression with fsverity enabled
   - potential deadlock when writing compressed pages
   - show missing mount options"

* tag 'f2fs-for-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (66 commits)
  f2fs: keep inline_data when compression conversion
  f2fs: fix to disable compression on directory
  f2fs: add missing CONFIG_F2FS_FS_COMPRESSION
  f2fs: switch discard_policy.timeout to bool type
  f2fs: fix to verify tpage before releasing in f2fs_free_dic()
  f2fs: show compression in statx
  f2fs: clean up dic->tpages assignment
  f2fs: compress: support zstd compress algorithm
  f2fs: compress: add .{init,destroy}_decompress_ctx callback
  f2fs: compress: fix to call missing destroy_compress_ctx()
  f2fs: change default compression algorithm
  f2fs: clean up {cic,dic}.ref handling
  f2fs: fix to use f2fs_readpage_limit() in f2fs_read_multi_pages()
  f2fs: xattr.h: Make stub helpers inline
  f2fs: fix to avoid double unlock
  f2fs: fix potential .flags overflow on 32bit architecture
  f2fs: fix NULL pointer dereference in f2fs_verity_work()
  f2fs: fix to clear PG_error if fsverity failed
  f2fs: don't call fscrypt_get_encryption_info() explicitly in f2fs_tmpfile()
  f2fs: don't trigger data flush in foreground operation
  ...

4 years agoMerge tag 'for-linus-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw...
Linus Torvalds [Tue, 7 Apr 2020 19:40:56 +0000 (12:40 -0700)]
Merge tag 'for-linus-5.7-rc1' of git://git./linux/kernel/git/rw/ubifs

Pull UBI and UBIFS updates from Richard Weinberger:

 - Fix for memory leaks around UBIFS orphan handling

 - Fix for memory leaks around UBI fastmap

 - Remove zero-length array from ubi-media.h

 - Fix for TNC lookup in UBIFS orphan code

* tag 'for-linus-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
  ubi: ubi-media.h: Replace zero-length array with flexible-array member
  ubifs: Fix out-of-bounds memory access caused by abnormal value of node_len
  ubi: fastmap: Only produce the initial anchor PEB when fastmap is used
  ubi: fastmap: Free unused fastmap anchor peb during detach
  ubifs: ubifs_add_orphan: Fix a memory leak bug
  ubifs: ubifs_jnl_write_inode: Fix a memory leak bug
  ubifs: Fix ubifs_tnc_lookup() usage in do_kill_orphans()

4 years agoMerge tag 'for-linus-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Linus Torvalds [Tue, 7 Apr 2020 19:36:09 +0000 (12:36 -0700)]
Merge tag 'for-linus-5.7-rc1' of git://git./linux/kernel/git/rw/uml

Pull UML updates from Richard Weinberger:

 - New mode for time travel, external via virtio

 - Fixes for ubd to make sure no requests can get lost

 - Fixes for vector networking

 - Allow CONFIG_STATIC_LINK only when possible

 - Minor cleanups and fixes

* tag 'for-linus-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  um: Remove some unnecessary NULL checks in vector_user.c
  um: vector: Avoid NULL ptr deference if transport is unset
  um: Make CONFIG_STATIC_LINK actually static
  um: Implement cpu_relax() as ndelay(1) for time-travel
  um: Implement ndelay/udelay in time-travel mode
  um: Implement time-travel=ext
  um: virtio: Implement VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS
  um: time-travel: Rewrite as an event scheduler
  um: Move timer-internal.h to non-shared
  hostfs: Use kasprintf() instead of fixed buffer formatting
  um: falloc.h needs to be directly included for older libc
  um: ubd: Retry buffer read on any kind of error
  um: ubd: Prevent buffer overrun on command completion
  um: Fix overlapping ELF segments when statically linked
  um: Delete never executed timer
  um: Don't overwrite ethtool driver version
  um: Fix len of file in create_pid_file
  um: Don't use console_drivers directly
  um: Cleanup CONFIG_IOSCHED_CFQ

4 years agoMerge tag 'for-linus' of git://github.com/openrisc/linux
Linus Torvalds [Tue, 7 Apr 2020 19:33:37 +0000 (12:33 -0700)]
Merge tag 'for-linus' of git://github.com/openrisc/linux

Pull OpenRISC updates from Stafford Horne:
 "A few cleanups all over the place, things of note:

   - Enable the clone3 syscall

   - Remove CONFIG_CROSS_COMPILE from Krzysztof Kozlowski

   - Update to use mmgrab from Julia Lawall"

* tag 'for-linus' of git://github.com/openrisc/linux:
  openrisc: Remove obsolete show_trace_task function
  openrisc: Cleanup copy_thread_tls docs and comments
  openrisc: Enable the clone3 syscall
  openrisc: Convert copy_thread to copy_thread_tls
  openrisc: use mmgrab
  openrisc: configs: Cleanup CONFIG_CROSS_COMPILE

4 years agoMerge branch 'parisc-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller...
Linus Torvalds [Tue, 7 Apr 2020 19:30:41 +0000 (12:30 -0700)]
Merge branch 'parisc-5.7-1' of git://git./linux/kernel/git/deller/parisc-linux

Pull parisc updates from Helge Deller:
 "Some cleanups in arch_rw locking functions, improved interrupt
  handling in arch spinlocks, coversions to request_irq() and syscall
  table generation cleanups"

* 'parisc-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: remove nargs from __SYSCALL
  parisc: Refactor alternative code to accept multiple conditions
  parisc: Rework arch_rw locking functions
  parisc: Improve interrupt handling in arch_spin_lock_flags()
  parisc: Replace setup_irq() by request_irq()

4 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc
Linus Torvalds [Tue, 7 Apr 2020 19:26:07 +0000 (12:26 -0700)]
Merge git://git./linux/kernel/git/davem/sparc

Pull sparc update from David Miller:
 "A per-device DMA ops conversion for sparc32 by Chrstioph Hellwig"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc32: use per-device dma_ops

4 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/davem/ide
Linus Torvalds [Tue, 7 Apr 2020 19:16:15 +0000 (12:16 -0700)]
Merge git://git./linux/kernel/git/davem/ide

Pull IDE update from David Miller:
 "As usual, very quiet in this subsystem.

  Just a list_for_each_entry_safe() conversion"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/ide:
  drivers/ide: Fix build regression.
  drivers/ide: convert to list_for_each_entry_safe()

4 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Linus Torvalds [Tue, 7 Apr 2020 19:03:32 +0000 (12:03 -0700)]
Merge git://git./linux/kernel/git/netdev/net

Pull networking fixes from David Miller:

 1) Slave bond and team devices should not be assigned ipv6 link local
    addresses, from Jarod Wilson.

 2) Fix clock sink config on some at803x PHY devices, from Oleksij
    Rempel.

 3) Uninitialized stack space transmitted in slcan frames, fix from
    Richard Palethorpe.

 4) Guard HW VLAN ops properly in stmmac driver, from Jose Abreu.

 5) "=" --> "|=" fix in aquantia driver, from Colin Ian King.

 6) Fix TCP fallback in mptcp, from Florian Westphal. (accessing a plain
    tcp_sk as if it were an mptcp socket).

 7) Fix cavium driver in some configurations wrt. PTP, from Yue Haibing.

 8) Make ipv6 and ipv4 consistent in the lower bound allowed for
    neighbour entry retrans_time, from Hangbin Liu.

 9) Don't use private workqueue in pegasus usb driver, from Petko
    Manolov.

10) Fix integer overflow in mlxsw, from Colin Ian King.

11) Missing refcnt init in cls_tcindex, from Cong Wang.

12) One too many loop iterations when processing cmpri entries in ipv6
    rpl code, from Alexander Aring.

13) Disable SG and TSO by default in r8169, from Heiner Kallweit.

14) NULL deref in macsec, from Davide Caratti.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (42 commits)
  macsec: fix NULL dereference in macsec_upd_offload()
  skbuff.h: Improve the checksum related comments
  net: dsa: bcm_sf2: Ensure correct sub-node is parsed
  qed: remove redundant assignment to variable 'rc'
  wimax: remove some redundant assignments to variable result
  mlxsw: spectrum_flower: Do not stop at FLOW_ACTION_VLAN_MANGLE
  mlxsw: spectrum_flower: Do not stop at FLOW_ACTION_PRIORITY
  r8169: change back SG and TSO to be disabled by default
  net: dsa: bcm_sf2: Do not register slave MDIO bus with OF
  ipv6: rpl: fix loop iteration
  tun: Don't put_page() for all negative return values from XDP program
  net: dsa: mt7530: fix null pointer dereferencing in port5 setup
  mptcp: add some missing pr_fmt defines
  net: phy: micrel: kszphy_resume(): add delay after genphy_resume() before accessing PHY registers
  net_sched: fix a missing refcnt in tcindex_init()
  net: stmmac: dwmac1000: fix out-of-bounds mac address reg setting
  mlxsw: spectrum_trap: fix unintention integer overflow on left shift
  pegasus: Remove pegasus' own workqueue
  neigh: support smaller retrans_time settting
  net: openvswitch: use hlist_for_each_entry_rcu instead of hlist_for_each_entry
  ...

4 years agoMerge branch 'pcmcia-next' of git://git.kernel.org/pub/scm/linux/kernel/git/brodo...
Linus Torvalds [Tue, 7 Apr 2020 18:01:37 +0000 (11:01 -0700)]
Merge branch 'pcmcia-next' of git://git./linux/kernel/git/brodo/linux

Pull pcmcia updates from Dominik Brodowski:
 "A few PCMCIA odd fixes: removing a few spaces and useless casts,
  replacing snprintf() with scnprintf(), and replacing zero-length
  arrays with a flexible-array member"

* 'pcmcia-next' of git://git.kernel.org/pub/scm/linux/kernel/git/brodo/linux:
  pcmcia: remove some unused space characters
  pcmcia: soc_common.h: Replace zero-length array with flexible-array member
  pcmcia: cs_internal.h: Replace zero-length array with flexible-array member
  pcmcia: Use scnprintf() for avoiding potential buffer overflow
  pcmcia: omap: remove useless cast for driver.name

4 years agoipc/shm.c: make compat_ksys_shmctl() static
Jason Yan [Tue, 7 Apr 2020 03:12:56 +0000 (20:12 -0700)]
ipc/shm.c: make compat_ksys_shmctl() static

Fix the following sparse warning:

ipc/shm.c:1335:6: warning: symbol 'compat_ksys_shmctl' was not declared.
Should it be static?

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200403063933.24785-1-yanaijie@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoipc/mqueue.c: fix a brace coding style issue
Somala Swaraj [Tue, 7 Apr 2020 03:12:53 +0000 (20:12 -0700)]
ipc/mqueue.c: fix a brace coding style issue

Signed-off-by: somala swaraj <somalaswaraj@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200301135530.18340-1-somalaswaraj@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/Kconfig.debug: fix a typo "capabilitiy" -> "capability"
Qiujun Huang [Tue, 7 Apr 2020 03:12:49 +0000 (20:12 -0700)]
lib/Kconfig.debug: fix a typo "capabilitiy" -> "capability"

s/capabilitiy/capability

Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1585818594-27373-1-git-send-email-hqjagain@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoubsan: include bug type in report header
Kees Cook [Tue, 7 Apr 2020 03:12:45 +0000 (20:12 -0700)]
ubsan: include bug type in report header

When syzbot tries to figure out how to deduplicate bug reports, it prefers
seeing a hint about a specific bug type (we can do better than just
"UBSAN").  This lifts the handler reason into the UBSAN report line that
includes the file path that tripped a check.  Unfortunately, UBSAN does
not provide function names.

Suggested-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Elena Petrova <lenaptr@google.com>
Cc: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Link: http://lkml.kernel.org/r/20200227193516.32566-7-keescook@chromium.org
Link: https://lore.kernel.org/lkml/CACT4Y+bsLJ-wFx_TaXqax3JByUOWB3uk787LsyMVcfW6JzzGvg@mail.gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agokasan: unset panic_on_warn before calling panic()
Kees Cook [Tue, 7 Apr 2020 03:12:42 +0000 (20:12 -0700)]
kasan: unset panic_on_warn before calling panic()

As done in the full WARN() handler, panic_on_warn needs to be cleared
before calling panic() to avoid recursive panics.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Elena Petrova <lenaptr@google.com>
Cc: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Link: http://lkml.kernel.org/r/20200227193516.32566-6-keescook@chromium.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoubsan: check panic_on_warn
Kees Cook [Tue, 7 Apr 2020 03:12:38 +0000 (20:12 -0700)]
ubsan: check panic_on_warn

Syzkaller expects kernel warnings to panic when the panic_on_warn sysctl
is set.  More work is needed here to have UBSan reuse the WARN
infrastructure, but for now, just check the flag manually.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Elena Petrova <lenaptr@google.com>
Cc: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Link: https://lore.kernel.org/lkml/CACT4Y+bsLJ-wFx_TaXqax3JByUOWB3uk787LsyMVcfW6JzzGvg@mail.gmail.com
Link: http://lkml.kernel.org/r/20200227193516.32566-5-keescook@chromium.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agodrivers/misc/lkdtm/bugs.c: add arithmetic overflow and array bounds checks
Kees Cook [Tue, 7 Apr 2020 03:12:34 +0000 (20:12 -0700)]
drivers/misc/lkdtm/bugs.c: add arithmetic overflow and array bounds checks

Adds LKDTM tests for arithmetic overflow (both signed and unsigned), as
well as array bounds checking.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Elena Petrova <lenaptr@google.com>
Cc: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Link: http://lkml.kernel.org/r/20200227193516.32566-4-keescook@chromium.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoubsan: split "bounds" checker from other options
Kees Cook [Tue, 7 Apr 2020 03:12:31 +0000 (20:12 -0700)]
ubsan: split "bounds" checker from other options

In order to do kernel builds with the bounds checker individually
available, introduce CONFIG_UBSAN_BOUNDS, with the remaining options under
CONFIG_UBSAN_MISC.

For example, using this, we can start to expand the coverage syzkaller is
providing.  Right now, all of UBSan is disabled for syzbot builds because
taken as a whole, it is too noisy.  This will let us focus on one feature
at a time.

For the bounds checker specifically, this provides a mechanism to
eliminate an entire class of array overflows with close to zero
performance overhead (I cannot measure a difference).  In my (mostly)
defconfig, enabling bounds checking adds ~4200 checks to the kernel.
Performance changes are in the noise, likely due to the branch predictors
optimizing for the non-fail path.

Some notes on the bounds checker:

- it does not instrument {mem,str}*()-family functions, it only
  instruments direct indexed accesses (e.g. "foo[i]"). Dealing with
  the {mem,str}*()-family functions is a work-in-progress around
  CONFIG_FORTIFY_SOURCE[1].

- it ignores flexible array members, including the very old single
  byte (e.g. "int foo[1];") declarations. (Note that GCC's
  implementation appears to ignore _all_ trailing arrays, but Clang only
  ignores empty, 0, and 1 byte arrays[2].)

[1] https://github.com/KSPP/linux/issues/6
[2] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92589

Suggested-by: Elena Petrova <lenaptr@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Link: http://lkml.kernel.org/r/20200227193516.32566-3-keescook@chromium.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoubsan: add trap instrumentation option
Kees Cook [Tue, 7 Apr 2020 03:12:27 +0000 (20:12 -0700)]
ubsan: add trap instrumentation option

Patch series "ubsan: Split out bounds checker", v5.

This splits out the bounds checker so it can be individually used.  This
is enabled in Android and hopefully for syzbot.  Includes LKDTM tests for
behavioral corner-cases (beyond just the bounds checker), and adjusts
ubsan and kasan slightly for correct panic handling.

This patch (of 6):

The Undefined Behavior Sanitizer can operate in two modes: warning
reporting mode via lib/ubsan.c handler calls, or trap mode, which uses
__builtin_trap() as the handler.  Using lib/ubsan.c means the kernel image
is about 5% larger (due to all the debugging text and reporting structures
to capture details about the warning conditions).  Using the trap mode,
the image size changes are much smaller, though at the loss of the
"warning only" mode.

In order to give greater flexibility to system builders that want minimal
changes to image size and are prepared to deal with kernel code being
aborted and potentially destabilizing the system, this introduces
CONFIG_UBSAN_TRAP.  The resulting image sizes comparison:

   text    data     bss       dec       hex     filename
19533663   6183037  18554956  44271656  2a38828 vmlinux.stock
19991849   7618513  18874448  46484810  2c54d4a vmlinux.ubsan
19712181   6284181  18366540  44362902  2a4ec96 vmlinux.ubsan-trap

CONFIG_UBSAN=y:      image +4.8% (text +2.3%, data +18.9%)
CONFIG_UBSAN_TRAP=y: image +0.2% (text +0.9%, data +1.6%)

Additionally adjusts the CONFIG_UBSAN Kconfig help for clarity and removes
the mention of non-existing boot param "ubsan_handle".

Suggested-by: Elena Petrova <lenaptr@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Link: http://lkml.kernel.org/r/20200227193516.32566-2-keescook@chromium.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoinit/Kconfig: clean up ANON_INODES and old IO schedulers options
Krzysztof Kozlowski [Tue, 7 Apr 2020 03:12:02 +0000 (20:12 -0700)]
init/Kconfig: clean up ANON_INODES and old IO schedulers options

CONFIG_ANON_INODES is gone since commit 5dd50aaeb185 ("Make anon_inodes
unconditional").

CONFIG_CFQ_GROUP_IOSCHED was replaced with CONFIG_BFQ_GROUP_IOSCHED in
commit f382fb0bcef4 ("block: remove legacy IO schedulers").

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: http://lkml.kernel.org/r/20200130192419.3026-1-krzk@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agokernel/gcov/fs.c: replace zero-length array with flexible-array member
Gustavo A. R. Silva [Tue, 7 Apr 2020 03:11:58 +0000 (20:11 -0700)]
kernel/gcov/fs.c: replace zero-length array with flexible-array member

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]

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 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Oberparleiter <oberpar@linux.ibm.com>
Link: http://lkml.kernel.org/r/20200302224851.GA26467@embeddedor
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agogcov: gcc_3_4: replace zero-length array with flexible-array member
Gustavo A. R. Silva [Tue, 7 Apr 2020 03:11:55 +0000 (20:11 -0700)]
gcov: gcc_3_4: replace zero-length array with flexible-array member

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]

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 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Oberparleiter <oberpar@linux.ibm.com>
Link: http://lkml.kernel.org/r/20200302224501.GA14175@embeddedor
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agogcov: gcc_4_7: replace zero-length array with flexible-array member
Gustavo A. R. Silva [Tue, 7 Apr 2020 03:11:52 +0000 (20:11 -0700)]
gcov: gcc_4_7: replace zero-length array with flexible-array member

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]

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 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Link: http://lkml.kernel.org/r/20200213152241.GA877@embeddedor
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agokernel/kmod.c: fix a typo "assuems" -> "assumes"
Qiujun Huang [Tue, 7 Apr 2020 03:11:49 +0000 (20:11 -0700)]
kernel/kmod.c: fix a typo "assuems" -> "assumes"

There is a typo in comment.  Fix it.  s/assuems/assumes/

Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Link: http://lkml.kernel.org/r/1585891029-6450-1-git-send-email-hqjagain@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoreiserfs: clean up several indentation issues
Colin Ian King [Tue, 7 Apr 2020 03:11:46 +0000 (20:11 -0700)]
reiserfs: clean up several indentation issues

There are several places where code is indented incorrectly. Fix these.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200325135018.113431-1-colin.king@canonical.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agokallsyms: unexport kallsyms_lookup_name() and kallsyms_on_each_symbol()
Will Deacon [Tue, 7 Apr 2020 03:11:43 +0000 (20:11 -0700)]
kallsyms: unexport kallsyms_lookup_name() and kallsyms_on_each_symbol()

kallsyms_lookup_name() and kallsyms_on_each_symbol() are exported to
modules despite having no in-tree users and being wide open to abuse by
out-of-tree modules that can use them as a method to invoke arbitrary
non-exported kernel functions.

Unexport kallsyms_lookup_name() and kallsyms_on_each_symbol().

Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Quentin Perret <qperret@google.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: http://lkml.kernel.org/r/20200221114404.14641-4-will@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agosamples/hw_breakpoint: drop use of kallsyms_lookup_name()
Will Deacon [Tue, 7 Apr 2020 03:11:39 +0000 (20:11 -0700)]
samples/hw_breakpoint: drop use of kallsyms_lookup_name()

The 'data_breakpoint' test code is the only modular user of
kallsyms_lookup_name(), which was exported as part of fixing the test in
f60d24d2ad04 ("hw-breakpoints: Fix broken hw-breakpoint sample module").

In preparation for un-exporting this symbol, switch the test over to using
__symbol_get(), which can be used to place breakpoints on exported
symbols.

Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Quentin Perret <qperret@google.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Link: http://lkml.kernel.org/r/20200221114404.14641-3-will@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agosamples/hw_breakpoint: drop HW_BREAKPOINT_R when reporting writes
Will Deacon [Tue, 7 Apr 2020 03:11:36 +0000 (20:11 -0700)]
samples/hw_breakpoint: drop HW_BREAKPOINT_R when reporting writes

Patch series "Unexport kallsyms_lookup_name() and kallsyms_on_each_symbol()".

Despite having just a single modular in-tree user that I could spot,
kallsyms_lookup_name() is exported to modules and provides a mechanism
for out-of-tree modules to access and invoke arbitrary, non-exported
kernel symbols when kallsyms is enabled.

This patch series fixes up that one user and unexports the symbol along
with kallsyms_on_each_symbol(), since that could also be abused in a
similar manner.

I would like to avoid out-of-tree modules being easily able to call
functions that are not exported.  kallsyms_lookup_name() makes this
trivial to the point that there is very little incentive to rework these
modules to either use upstream interfaces correctly or propose
functionality which may be otherwise missing upstream.  Both of these
latter solutions would be pre-requisites to upstreaming these modules, and
the current state of things actively discourages that approach.

The background here is that we are aiming for Android devices to be able
to use a generic binary kernel image closely following upstream, with any
vendor extensions coming in as kernel modules.  In this case, we (Google)
end up maintaining the binary module ABI within the scope of a single LTS
kernel.  Monitoring and managing the ABI surface is not feasible if it
effectively includes all data and functions via kallsyms_lookup_name().
Of course, we could just carry this patch in the Android kernel tree, but
we're aiming to carry as little as possible (ideally nothing) and I think
it's a sensible change in its own right.  I'm surprised you object to it,
in all honesty.

Now, you could turn around and say "that's not upstream's problem", but it
still seems highly undesirable to me to have an upstream bypass for
exported symbols that isn't even used by upstream modules.  It's ripe for
abuse and encourages people to work outside of the upstream tree.  The
usual rule is that we don't export symbols without a user in the tree and
that seems especially relevant in this case.

Joe Lawrence said:

: FWIW, kallsyms was historically used by the out-of-tree kpatch support
: module to resolve external symbols as well as call set_memory_r{w,o}()
: API.  All of that support code has been merged upstream, so modern kpatch
: modules* no longer leverage kallsyms by default.
:
: That said, there are still some users who still use the deprecated support
: module with newer kernels, but that is not officially supported by the
: project.

This patch (of 3):

Given the name of a kernel symbol, the 'data_breakpoint' test claims to
"report any write operations on the kernel symbol".  However, it creates
the breakpoint using both HW_BREAKPOINT_W and HW_BREAKPOINT_R, which menas
it also fires for read access.

Drop HW_BREAKPOINT_R from the breakpoint attributes.

Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Quentin Perret <qperret@google.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Link: http://lkml.kernel.org/r/20200221114404.14641-2-will@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agofs/binfmt_elf.c: don't free interpreter's ELF pheaders on common path
Alexey Dobriyan [Tue, 7 Apr 2020 03:11:32 +0000 (20:11 -0700)]
fs/binfmt_elf.c: don't free interpreter's ELF pheaders on common path

Static executables don't need to free NULL pointer.

It doesn't matter really because static executable is not common scenario
but do it anyway out of pedantry.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200219185330.GA4933@avx2
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agofs/binfmt_elf.c: allocate less for static executable
Alexey Dobriyan [Tue, 7 Apr 2020 03:11:29 +0000 (20:11 -0700)]
fs/binfmt_elf.c: allocate less for static executable

PT_INTERP ELF header can be spared if executable is static.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200219185012.GB4871@avx2
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agofs/binfmt_elf.c: delete "loc" variable
Alexey Dobriyan [Tue, 7 Apr 2020 03:11:26 +0000 (20:11 -0700)]
fs/binfmt_elf.c: delete "loc" variable

"loc" variable became just a wrapper for PT_INTERP ELF header after main
ELF header was moved to "bprm->buf".  Delete it.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200219184847.GA4871@avx2
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agofs/epoll: make nesting accounting safe for -rt kernel
Jason Baron [Tue, 7 Apr 2020 03:11:23 +0000 (20:11 -0700)]
fs/epoll: make nesting accounting safe for -rt kernel

Davidlohr Bueso pointed out that when CONFIG_DEBUG_LOCK_ALLOC is set
ep_poll_safewake() can take several non-raw spinlocks after disabling
interrupts.  Since a spinlock can block in the -rt kernel, we can't take a
spinlock after disabling interrupts.  So let's re-work how we determine
the nesting level such that it plays nicely with the -rt kernel.

Let's introduce a 'nests' field in struct eventpoll that records the
current nesting level during ep_poll_callback().  Then, if we nest again
we can find the previous struct eventpoll that we were called from and
increase our count by 1.  The 'nests' field is protected by
ep->poll_wait.lock.

I've also moved the visited field to reduce the size of struct eventpoll
from 184 bytes to 176 bytes on x86_64 for !CONFIG_DEBUG_LOCK_ALLOC, which
is typical for a production config.

Reported-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Jason Baron <jbaron@akamai.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Roman Penyaev <rpenyaev@suse.de>
Cc: Eric Wong <normalperson@yhbt.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Link: http://lkml.kernel.org/r/1582739816-13167-1-git-send-email-jbaron@akamai.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agokselftest: introduce new epoll test case
Roman Penyaev [Tue, 7 Apr 2020 03:11:20 +0000 (20:11 -0700)]
kselftest: introduce new epoll test case

This testcase repeats epollbug.c from the bug:

  https://bugzilla.kernel.org/show_bug.cgi?id=205933

What it tests?  It tests the race between epoll_ctl() and epoll_wait().
New event mask passed to epoll_ctl() triggers wake up, which can be missed
because of the bug described in the link.  Reproduction is 100%, so easy
to fix.  Kudos, Max, for wonderful test case.

Signed-off-by: Roman Penyaev <rpenyaev@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Max Neunhoeffer <max@arangodb.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Christopher Kohlhoff <chris.kohlhoff@clearpool.io>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Jes Sorensen <jes.sorensen@gmail.com>
Link: http://lkml.kernel.org/r/20200214170211.561524-2-rpenyaev@suse.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agocheckpatch: avoid warning about uninitialized_var()
Joe Perches [Tue, 7 Apr 2020 03:11:17 +0000 (20:11 -0700)]
checkpatch: avoid warning about uninitialized_var()

WARNING: function definition argument 'flags' should also have an identifier name
#26: FILE: drivers/tty/serial/sh-sci.c:1348:
+       unsigned long uninitialized_var(flags);

Special-case uninitialized_var() to prevent this.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/7db7944761b0bd88c70eb17d4b7f40fe589e14ed.camel@perches.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agocheckpatch: check proper licensing of Devicetree bindings
Lubomir Rintel [Tue, 7 Apr 2020 03:11:13 +0000 (20:11 -0700)]
checkpatch: check proper licensing of Devicetree bindings

According to Devicetree maintainers (see Link: below), the Devicetree
binding documents are preferrably licensed (GPL-2.0-only OR BSD-2-Clause).

Let's check that.  The actual check is a bit more relaxed, to allow more
liberal but compatible licensing (e.g.  GPL-2.0-or-later OR BSD-2-Clause).

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Joe Perches <joe@perches.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>,
Cc: Jonas Karlman <jonas@kwiboo.se>,
Cc: Jernej Skrabec <jernej.skrabec@siol.net>,
Cc: Mark Rutland <mark.rutland@arm.com>,
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>,
Link: https://lore.kernel.org/lkml/20200108142132.GA4830@bogus/
Link: http://lkml.kernel.org/r/20200309215153.38824-1-lkundrak@v3.sk
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agocheckpatch: improve Gerrit Change-Id: test
Joe Perches [Tue, 7 Apr 2020 03:11:10 +0000 (20:11 -0700)]
checkpatch: improve Gerrit Change-Id: test

The Gerrit Change-Id: entry is sometimes placed after a Signed-off-by:
line.  When this occurs, the Gerrit warning is not currently emitted as
the first Signed-off-by: signature sets a flag to stop looking.

Change the test to add a test for the --- patch separator and emit the
warning before any before the --- and also before any diff file name.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/2f6d5f8766fe7439a116c77ea8cc721a3f2d77a2.camel@perches.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agocheckpatch: add command-line option for TAB size
Antonio Borneo [Tue, 7 Apr 2020 03:11:07 +0000 (20:11 -0700)]
checkpatch: add command-line option for TAB size

Linux kernel coding style requires a size of 8 characters for both TAB and
indentation, and such value is embedded as magic value allover the
checkpatch script.

This makes hard to reuse the script by other projects with different
requirements in their coding style (e.g.  OpenOCD [1] requires TAB size of
4 characters [2]).

Replace the magic value 8 with a variable.

Add a command-line option "--tab-size" to let the user select a
TAB size value other than 8.

[1] http://openocd.org/
[2] http://openocd.org/doc/doxygen/html/stylec.html#styleformat

Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Signed-off-by: Erik Ahlén <erik.ahlen@avalonenterprise.com>
Signed-off-by: Spencer Oliver <spen@spen-soft.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Joe Perches <joe@perches.com>
Link: http://lkml.kernel.org/r/20200122163852.124417-3-borneo.antonio@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agocheckpatch: fix multiple const * types
Antonio Borneo [Tue, 7 Apr 2020 03:11:04 +0000 (20:11 -0700)]
checkpatch: fix multiple const * types

Commit 1574a29f8e76 ("checkpatch: allow multiple const * types") claims to
support repetition of pattern "const *", but it actually allows only one
extra instance.

Check the following lines
int a(char const * const x[]);
int b(char const * const *x);
int c(char const * const * const x[]);
int d(char const * const * const *x);

with command

./scripts/checkpatch.pl --show-types -f filename

to find that only the first line passes the test, while a warning
is triggered by the other 3 lines:

WARNING:FUNCTION_ARGUMENTS: function definition argument
'char const * const' should also have an identifier name

The reason is that the pattern match halts at the second asterisk in the
line, thus the remaining text starting with asterisk fails to match a
valid name for a variable.

Fixed by replacing "?" (Match 1 or 0 times) with "{0,4}" (Match no more
than 4 times) in the regular expression.  Fix also the similar test for
types in unusual order.

Fixes: 1574a29f8e76 ("checkpatch: allow multiple const * types")
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Joe Perches <joe@perches.com>
Link: http://lkml.kernel.org/r/20200122163852.124417-1-borneo.antonio@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agocheckpatch: fix minor typo and mixed space+tab in indentation
Antonio Borneo [Tue, 7 Apr 2020 03:11:01 +0000 (20:11 -0700)]
checkpatch: fix minor typo and mixed space+tab in indentation

Fix spelling of "concatenation".
Don't use tab after space in indentation.

Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Joe Perches <joe@perches.com>
Link: http://lkml.kernel.org/r/20200122163852.124417-2-borneo.antonio@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agocheckpatch: prefer fallthrough; over fallthrough comments
Joe Perches [Tue, 7 Apr 2020 03:10:58 +0000 (20:10 -0700)]
checkpatch: prefer fallthrough; over fallthrough comments

commit 294f69e662d1 ("compiler_attributes.h: Add 'fallthrough' pseudo
keyword for switch/case use") added the pseudo keyword so add a test for
it to checkpatch.

Warn on a patch or use --strict for files.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/8b6c1b9031ab9f3cdebada06b8d46467f1492d68.camel@perches.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agocheckpatch: support "base-commit:" format
John Hubbard [Tue, 7 Apr 2020 03:10:55 +0000 (20:10 -0700)]
checkpatch: support "base-commit:" format

In order to support the get-lore-mbox.py tool described in [1], I ran:

    git format-patch --base=<commit> --cover-letter <revrange>

...  which generated a "base-commit: <commit-hash>" tag at the end of the
cover letter.  However, checkpatch.pl generated an error upon encounting
"base-commit:" in the cover letter:

    "ERROR: Please use git commit description style..."

...  because it found the "commit" keyword, and failed to recognize that
it was part of the "base-commit" phrase, and as such, should not be
subjected to the same commit description style rules.

Update checkpatch.pl to include a special case for "base-commit:" (at the
start of the line, possibly with some leading whitespace) so that that tag
no longer generates a checkpatch error.

[1] https://lwn.net/Articles/811528/ "Better tools for kernel
    developers"

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Konstantin Ryabitsev <konstantin@linuxfoundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Link: http://lkml.kernel.org/r/20200213055004.69235-2-jhubbard@nvidia.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agocheckpatch: check SPDX tags in YAML files
Lubomir Rintel [Tue, 7 Apr 2020 03:10:51 +0000 (20:10 -0700)]
checkpatch: check SPDX tags in YAML files

This adds a warning when a YAML file is lacking a SPDX header on first
line, or it uses incorrect commenting style.

Currently the only YAML files in the tree are Devicetree binding
documents.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Joe Perches <joe@perches.com>
Cc: Rob Herring <robh@kernel.org>
Link: http://lkml.kernel.org/r/20200129123356.388669-1-lkundrak@v3.sk
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agocheckpatch: remove email address comment from email address comparisons
Joe Perches [Tue, 7 Apr 2020 03:10:48 +0000 (20:10 -0700)]
checkpatch: remove email address comment from email address comparisons

About 2% of the last 100K commits have email addresses that include an
RFC2822 compliant comment like:

Peter Zijlstra (Intel) <peterz@infradead.org>

checkpatch currently does a comparison of the complete name and address to
the submitted author to determine if the author has signed-off and emits a
warning if the exact email names and addresses do not match.

Unfortunately, the author email address can be written without the comment
like:

Peter Zijlstra <peterz@infradead.org>

Add logic to compare the comment stripped email addresses to avoid this
warning.

Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/ebaa2f7c8f94e25520981945cddcc1982e70e072.camel@perches.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/dynamic_debug.c: use address-of operator on section symbols
Nathan Chancellor [Tue, 7 Apr 2020 03:10:45 +0000 (20:10 -0700)]
lib/dynamic_debug.c: use address-of operator on section symbols

Clang warns:

../lib/dynamic_debug.c:1034:24: warning: array comparison always
evaluates to false [-Wtautological-compare]
        if (__start___verbose == __stop___verbose) {
                              ^
1 warning generated.

These are not true arrays, they are linker defined symbols, which are just
addresses.  Using the address of operator silences the warning and does
not change the resulting assembly with either clang/ld.lld or gcc/ld
(tested with diff + objdump -Dr).

Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Jason Baron <jbaron@akamai.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/894
Link: http://lkml.kernel.org/r/20200220051320.10739-1-natechancellor@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolinux/bits.h: add compile time sanity check of GENMASK inputs
Rikard Falkeborn [Tue, 7 Apr 2020 03:10:38 +0000 (20:10 -0700)]
linux/bits.h: add compile time sanity check of GENMASK inputs

GENMASK() and GENMASK_ULL() are supposed to be called with the high bit as
the first argument and the low bit as the second argument.  Mixing them
will return a mask with zero bits set.

Recent commits show getting this wrong is not uncommon, see e.g.  commit
aa4c0c9091b0 ("net: stmmac: Fix misuses of GENMASK macro") and commit
9bdd7bb3a844 ("clocksource/drivers/npcm: Fix misuse of GENMASK macro").

To prevent such mistakes from appearing again, add compile time sanity
checking to the arguments of GENMASK() and GENMASK_ULL().  If both
arguments are known at compile time, and the low bit is higher than the
high bit, break the build to detect the mistake immediately.

Since GENMASK() is used in declarations, BUILD_BUG_ON_ZERO() must be used
instead of BUILD_BUG_ON().

__builtin_constant_p does not evaluate is argument, it only checks if it
is a constant or not at compile time, and __builtin_choose_expr does not
evaluate the expression that is not chosen.  Therefore, GENMASK(x++, 0)
does only evaluate x++ once.

Commit 95b980d62d52 ("linux/bits.h: make BIT(), GENMASK(), and friends
available in assembly") made the macros in linux/bits.h available in
assembly.  Since BUILD_BUG_OR_ZERO() is not asm compatible, disable the
checks if the file is included in an asm file.

Due to bugs in GCC versions before 4.9 [0], disable the check if building
with a too old GCC compiler.

[0]: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=19449

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Haren Myneni <haren@us.ibm.com>
Cc: Joe Perches <joe@perches.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: lkml <linux-kernel@vger.kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200308193954.2372399-1-rikard.falkeborn@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/test_kmod.c: remove a NULL test
Dan Carpenter [Tue, 7 Apr 2020 03:10:35 +0000 (20:10 -0700)]
lib/test_kmod.c: remove a NULL test

The "info" pointer has already been dereferenced so checking here is too
late.  Fortunately, we never pass NULL pointers to the
test_kmod_put_module() function so the test can simply be removed.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Link: http://lkml.kernel.org/r/20200228092452.vwkhthsn77nrxdy6@kili.mountain
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/rbtree: fix coding style of assignments
chenqiwu [Tue, 7 Apr 2020 03:10:31 +0000 (20:10 -0700)]
lib/rbtree: fix coding style of assignments

Leave blank space between the right-hand and left-hand side of the
assignment to meet the kernel coding style better.

Signed-off-by: chenqiwu <chenqiwu@xiaomi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Michel Lespinasse <walken@google.com>
Link: http://lkml.kernel.org/r/1582621140-25850-1-git-send-email-qiwuchen55@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/test_bitmap.c: make use of EXP2_IN_BITS
Andy Shevchenko [Tue, 7 Apr 2020 03:10:28 +0000 (20:10 -0700)]
lib/test_bitmap.c: make use of EXP2_IN_BITS

Commit 30544ed5de43 ("lib/bitmap: introduce bitmap_replace() helper")
introduced some new test cases to the test_bitmap.c module.  Among these
it also introduced an (unused) definition.  Let's make use of
EXP2_IN_BITS.

Reported-by: Alex Shi <alex.shi@linux.alibaba.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Alex Shi <alex.shi@linux.alibaba.com>
Link: http://lkml.kernel.org/r/20200121151847.75223-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agopercpu_counter: fix a data race at vm_committed_as
Qian Cai [Tue, 7 Apr 2020 03:10:25 +0000 (20:10 -0700)]
percpu_counter: fix a data race at vm_committed_as

"vm_committed_as.count" could be accessed concurrently as reported by
KCSAN,

 BUG: KCSAN: data-race in __vm_enough_memory / percpu_counter_add_batch

 write to 0xffffffff9451c538 of 8 bytes by task 65879 on cpu 35:
  percpu_counter_add_batch+0x83/0xd0
  percpu_counter_add_batch at lib/percpu_counter.c:91
  __vm_enough_memory+0xb9/0x260
  dup_mm+0x3a4/0x8f0
  copy_process+0x2458/0x3240
  _do_fork+0xaa/0x9f0
  __do_sys_clone+0x125/0x160
  __x64_sys_clone+0x70/0x90
  do_syscall_64+0x91/0xb05
  entry_SYSCALL_64_after_hwframe+0x49/0xbe

 read to 0xffffffff9451c538 of 8 bytes by task 66773 on cpu 19:
  __vm_enough_memory+0x199/0x260
  percpu_counter_read_positive at include/linux/percpu_counter.h:81
  (inlined by) __vm_enough_memory at mm/util.c:839
  mmap_region+0x1b2/0xa10
  do_mmap+0x45c/0x700
  vm_mmap_pgoff+0xc0/0x130
  ksys_mmap_pgoff+0x6e/0x300
  __x64_sys_mmap+0x33/0x40
  do_syscall_64+0x91/0xb05
  entry_SYSCALL_64_after_hwframe+0x49/0xbe

The read is outside percpu_counter::lock critical section which results in
a data race.  Fix it by adding a READ_ONCE() in
percpu_counter_read_positive() which could also service as the existing
compiler memory barrier.

Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Marco Elver <elver@google.com>
Link: http://lkml.kernel.org/r/1582302724-2804-1-git-send-email-cai@lca.pw
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agokasan: stackdepot: move filter_irq_stacks() to stackdepot.c
Alexander Potapenko [Tue, 7 Apr 2020 03:10:22 +0000 (20:10 -0700)]
kasan: stackdepot: move filter_irq_stacks() to stackdepot.c

filter_irq_stacks() can be used by other tools (e.g.  KMSAN), so it needs
to be moved to a common location.  lib/stackdepot.c seems a good place, as
filter_irq_stacks() is usually applied to the output of
stack_trace_save().

This patch has been previously mailed as part of KMSAN RFC patch series.

[glider@google.co: nds32: linker script: add SOFTIRQENTRY_TEXT\
Link: http://lkml.kernel.org/r/20200311121002.241430-1-glider@google.com
[glider@google.com: add IRQENTRY_TEXT and SOFTIRQENTRY_TEXT to linker script]
Link: http://lkml.kernel.org/r/20200311121124.243352-1-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Link: http://lkml.kernel.org/r/20200220141916.55455-3-glider@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/stackdepot.c: build with -fno-builtin
Alexander Potapenko [Tue, 7 Apr 2020 03:10:19 +0000 (20:10 -0700)]
lib/stackdepot.c: build with -fno-builtin

Clang may replace stackdepot_memcmp() with a call to instrumented bcmp(),
which is exactly what we wanted to avoid creating stackdepot_memcmp().
Building the file with -fno-builtin prevents such optimizations.

This patch has been previously mailed as part of KMSAN RFC patch series.

Signed-off-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Link: http://lkml.kernel.org/r/20200220141916.55455-2-glider@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/stackdepot.c: check depot_index before accessing the stack slab
Alexander Potapenko [Tue, 7 Apr 2020 03:10:15 +0000 (20:10 -0700)]
lib/stackdepot.c: check depot_index before accessing the stack slab

Avoid crashes on corrupted stack ids.  Despite stack ID corruption may
indicate other bugs in the program, we'd better fail gracefully on such
IDs instead of crashing the kernel.

This patch has been previously mailed as part of KMSAN RFC patch series.

Link: http://lkml.kernel.org/r/20200220141916.55455-1-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
From: Dan Carpenter <dan.carpenter@oracle.com>
Subject: lib/stackdepot.c: fix a condition in stack_depot_fetch()

We should check for a NULL pointer first before adding the offset.
Otherwise if the pointer is NULL and the offset is non-zero, it will lead
to an Oops.

Fixes: d45048e65a59 ("lib/stackdepot.c: check depot_index before accessing the stack slab")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Alexander Potapenko <glider@google.com>
Link: http://lkml.kernel.org/r/20200312113006.GA20562@mwanda
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib: test_stackinit.c: XFAIL switch variable init tests
Kees Cook [Tue, 7 Apr 2020 03:10:12 +0000 (20:10 -0700)]
lib: test_stackinit.c: XFAIL switch variable init tests

The tests for initializing a variable defined between a switch statement's
test and its first "case" statement are currently not initialized in
Clang[1] nor the proposed auto-initialization feature in GCC.

We should retain the test (so that we can evaluate compiler fixes), but
mark it as an "expected fail".  The rest of the kernel source will be
adjusted to avoid this corner case.

Also disable -Wswitch-unreachable for the test so that the intentionally
broken code won't trigger warnings for GCC (nor future Clang) when
initialization happens this unhandled place.

[1] https://bugs.llvm.org/show_bug.cgi?id=44916

Suggested-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Jann Horn <jannh@google.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Link: http://lkml.kernel.org/r/202002191358.2897A07C6@keescook
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/scatterlist: fix sg_copy_buffer() kerneldoc
Geert Uytterhoeven [Tue, 7 Apr 2020 03:10:09 +0000 (20:10 -0700)]
lib/scatterlist: fix sg_copy_buffer() kerneldoc

Add the missing closing parenthesis to the description for the to_buffer
parameter of sg_copy_buffer().

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Akinobu Mita <akinobu.mita@gmail.com
Link: http://lkml.kernel.org/r/20200212084241.8778-1-geert+renesas@glider.be
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/ts_kmp.c: replace zero-length array with flexible-array member
Gustavo A. R. Silva [Tue, 7 Apr 2020 03:10:06 +0000 (20:10 -0700)]
lib/ts_kmp.c: replace zero-length array with flexible-array member

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
inadvertenly introduced[3] to the codebase from now on.

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 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200211205948.GA26459@embeddedor
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/ts_fsm.c: replace zero-length array with flexible-array member
Gustavo A. R. Silva [Tue, 7 Apr 2020 03:10:03 +0000 (20:10 -0700)]
lib/ts_fsm.c: replace zero-length array with flexible-array member

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
inadvertenly introduced[3] to the codebase from now on.

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 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200211205813.GA25602@embeddedor
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/ts_bm.c: replace zero-length array with flexible-array member
Gustavo A. R. Silva [Tue, 7 Apr 2020 03:10:00 +0000 (20:10 -0700)]
lib/ts_bm.c: replace zero-length array with flexible-array member

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
inadvertenly introduced[3] to the codebase from now on.

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 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200211205620.GA24694@embeddedor
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agolib/bch.c: replace zero-length array with flexible-array member
Gustavo A. R. Silva [Tue, 7 Apr 2020 03:09:57 +0000 (20:09 -0700)]
lib/bch.c: replace zero-length array with flexible-array member

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
inadvertenly introduced[3] to the codebase from now on.

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 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200211205119.GA21234@embeddedor
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>