Commit Graph

762 Commits

Author SHA1 Message Date
6adc19fd13 Merge tag 'kbuild-v5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull more Kbuild updates from Masahiro Yamada:

 - fix build rules in binderfs sample

 - fix build errors when Kbuild recurses to the top Makefile

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

* tag 'kbuild-v5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  treewide: replace '---help---' in Kconfig files with 'help'
  kbuild: fix broken builds because of GZIP,BZIP2,LZOP variables
  samples: binderfs: really compile this sample and fix build issues
2020-06-13 13:29:16 -07:00
a7f7f6248d treewide: replace '---help---' in Kconfig files with 'help'
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.

This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.

There are a variety of indentation styles found.

  a) 4 spaces + '---help---'
  b) 7 spaces + '---help---'
  c) 8 spaces + '---help---'
  d) 1 space + 1 tab + '---help---'
  e) 1 tab + '---help---'    (correct indentation)
  f) 1 tab + 1 space + '---help---'
  g) 1 tab + 2 spaces + '---help---'

In order to convert all of them to 1 tab + 'help', I ran the
following commend:

  $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-14 01:57:21 +09:00
b791d1bdf9 Merge tag 'locking-kcsan-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull the Kernel Concurrency Sanitizer from Thomas Gleixner:
 "The Kernel Concurrency Sanitizer (KCSAN) is a dynamic race detector,
  which relies on compile-time instrumentation, and uses a
  watchpoint-based sampling approach to detect races.

  The feature was under development for quite some time and has already
  found legitimate bugs.

  Unfortunately it comes with a limitation, which was only understood
  late in the development cycle:

     It requires an up to date CLANG-11 compiler

  CLANG-11 is not yet released (scheduled for June), but it's the only
  compiler today which handles the kernel requirements and especially
  the annotations of functions to exclude them from KCSAN
  instrumentation correctly.

  These annotations really need to work so that low level entry code and
  especially int3 text poke handling can be completely isolated.

  A detailed discussion of the requirements and compiler issues can be
  found here:

    https://lore.kernel.org/lkml/CANpmjNMTsY_8241bS7=XAfqvZHFLrVEkv_uM4aDUWE_kh3Rvbw@mail.gmail.com/

  We came to the conclusion that trying to work around compiler
  limitations and bugs again would end up in a major trainwreck, so
  requiring a working compiler seemed to be the best choice.

  For Continous Integration purposes the compiler restriction is
  manageable and that's where most xxSAN reports come from.

  For a change this limitation might make GCC people actually look at
  their bugs. Some issues with CSAN in GCC are 7 years old and one has
  been 'fixed' 3 years ago with a half baken solution which 'solved' the
  reported issue but not the underlying problem.

  The KCSAN developers also ponder to use a GCC plugin to become
  independent, but that's not something which will show up in a few
  days.

  Blocking KCSAN until wide spread compiler support is available is not
  a really good alternative because the continuous growth of lockless
  optimizations in the kernel demands proper tooling support"

* tag 'locking-kcsan-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (76 commits)
  compiler_types.h, kasan: Use __SANITIZE_ADDRESS__ instead of CONFIG_KASAN to decide inlining
  compiler.h: Move function attributes to compiler_types.h
  compiler.h: Avoid nested statement expression in data_race()
  compiler.h: Remove data_race() and unnecessary checks from {READ,WRITE}_ONCE()
  kcsan: Update Documentation to change supported compilers
  kcsan: Remove 'noinline' from __no_kcsan_or_inline
  kcsan: Pass option tsan-instrument-read-before-write to Clang
  kcsan: Support distinguishing volatile accesses
  kcsan: Restrict supported compilers
  kcsan: Avoid inserting __tsan_func_entry/exit if possible
  ubsan, kcsan: Don't combine sanitizer with kcov on clang
  objtool, kcsan: Add kcsan_disable_current() and kcsan_enable_current_nowarn()
  kcsan: Add __kcsan_{enable,disable}_current() variants
  checkpatch: Warn about data_race() without comment
  kcsan: Use GFP_ATOMIC under spin lock
  Improve KCSAN documentation a bit
  kcsan: Make reporting aware of KCSAN tests
  kcsan: Fix function matching in report
  kcsan: Change data_race() to no longer require marking racing accesses
  kcsan: Move kcsan_{disable,enable}_current() to kcsan-checks.h
  ...
2020-06-11 18:55:43 -07:00
37d1a04b13 Rebase locking/kcsan to locking/urgent
Merge the state of the locking kcsan branch before the read/write_once()
and the atomics modifications got merged.

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

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2020-06-11 20:02:46 +02:00
6af132f3a1 lib: test get_count_order/long in test_bitops.c
Add some tests for get_count_order/long in test_bitops.c.

[akpm@linux-foundation.org: define local `i']
[akpm@linux-foundation.org: enhancement, warning fix, cleanup per Geert]
[akpm@linux-foundation.org: fix loop bound, per Wei Yang]

Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Link: http://lkml.kernel.org/r/20200602223728.32722-1-richard.weiyang@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-10 19:14:18 -07:00
595a56ac1b Merge tag 'linux-kselftest-kunit-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull Kunit updates from Shuah Khan:
 "This consists of:

   - Several config fragment fixes from Anders Roxell to improve test
     coverage.

   - Improvements to kunit run script to use defconfig as default and
     restructure the code for config/build/exec/parse from Vitor Massaru
     Iha and David Gow.

   - Miscellaneous documentation warn fix"

* tag 'linux-kselftest-kunit-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  security: apparmor: default KUNIT_* fragments to KUNIT_ALL_TESTS
  fs: ext4: default KUNIT_* fragments to KUNIT_ALL_TESTS
  drivers: base: default KUNIT_* fragments to KUNIT_ALL_TESTS
  lib: Kconfig.debug: default KUNIT_* fragments to KUNIT_ALL_TESTS
  kunit: default KUNIT_* fragments to KUNIT_ALL_TESTS
  kunit: Kconfig: enable a KUNIT_ALL_TESTS fragment
  kunit: Fix TabError, remove defconfig code and handle when there is no kunitconfig
  kunit: use KUnit defconfig by default
  kunit: use --build_dir=.kunit as default
  Documentation: test.h - fix warnings
  kunit: kunit_tool: Separate out config/build/exec/parse
2020-06-09 10:04:47 -07:00
ceabef7dd7 dynamic_debug: add an option to enable dynamic debug for modules only
Instead of enabling dynamic debug globally with CONFIG_DYNAMIC_DEBUG,
CONFIG_DYNAMIC_DEBUG_CORE will only enable core function of dynamic
debug.  With the DYNAMIC_DEBUG_MODULE defined for any modules, dynamic
debug will be tied to them.

This is useful for people who only want to enable dynamic debug for
kernel modules without worrying about kernel image size and memory
consumption is increasing too much.

[orson.zhai@unisoc.com: v2]
  Link: http://lkml.kernel.org/r/1587408228-10861-1-git-send-email-orson.unisoc@gmail.com

Signed-off-by: Orson Zhai <orson.zhai@unisoc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Petr Mladek <pmladek@suse.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Link: http://lkml.kernel.org/r/1586521984-5890-1-git-send-email-orson.unisoc@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-08 11:05:56 -07:00
cff11abeca Merge tag 'kbuild-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:

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

 - ensure to rebuild all objects when the compiler is upgraded

 - exclude system headers from dependency tracking and fixdep processing

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

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

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

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

 - sanitize the output format of scripts/checkstack.pl

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

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

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

 - add CONFIG_DEBUG_INFO_COMPRESSED to support compressed debug info

 - a lot of cleanups of modpost

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

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

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

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

* tag 'kbuild-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (96 commits)
  kbuild: add variables for compression tools
  Makefile: install modules.builtin even if CONFIG_MODULES=n
  mksysmap: Fix the mismatch of '.L' symbols in System.map
  kbuild: doc: rename LDFLAGS to KBUILD_LDFLAGS
  modpost: change elf_info->size to size_t
  modpost: remove is_vmlinux() helper
  modpost: strip .o from modname before calling new_module()
  modpost: set have_vmlinux in new_module()
  modpost: remove mod->skip struct member
  modpost: add mod->is_vmlinux struct member
  modpost: remove is_vmlinux() call in check_for_{gpl_usage,unused}()
  modpost: remove mod->is_dot_o struct member
  modpost: move -d option in scripts/Makefile.modpost
  modpost: remove -s option
  modpost: remove get_next_text() and make {grab,release_}file static
  modpost: use read_text_file() and get_line() for reading text files
  modpost: avoid false-positive file open error
  modpost: fix potential mmap'ed file overrun in get_src_version()
  modpost: add read_text_file() and get_line() helpers
  modpost: do not call get_modinfo() for vmlinux(.o)
  ...
2020-06-06 12:00:25 -07:00
c348c16305 lib: make a test module with set/clear bit
Test some bit clears/sets to make sure assembly doesn't change, and that
the set_bit and clear_bit functions work and don't cause sparse warnings.

Instruct Kbuild to build this file with extra warning level -Wextra, to
catch new issues, and also doesn't hurt to build with C=1.

This was used to test changes to arch/x86/include/asm/bitops.h.

In particular, sparse (C=1) was very concerned when the last bit before a
natural boundary, like 7, or 31, was being tested, as this causes sign
extension (0xffffff7f) for instance when clearing bit 7.

Recommended usage:

  make defconfig
  scripts/config -m CONFIG_TEST_BITOPS
  make modules_prepare
  make C=1 W=1 lib/test_bitops.ko
  objdump -S -d lib/test_bitops.ko
  insmod lib/test_bitops.ko
  rmmod lib/test_bitops.ko

<check dmesg>, there should be no compiler/sparse warnings and no
error messages in log.

Link: http://lkml.kernel.org/r/20200310221747.2848474-2-jesse.brandeburg@intel.com
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
CcL Ingo Molnar <mingo@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04 19:06:25 -07:00
399145f9eb mm/debug: add tests validating architecture page table helpers
This adds tests which will validate architecture page table helpers and
other accessors in their compliance with expected generic MM semantics.
This will help various architectures in validating changes to existing
page table helpers or addition of new ones.

This test covers basic page table entry transformations including but not
limited to old, young, dirty, clean, write, write protect etc at various
level along with populating intermediate entries with next page table page
and validating them.

Test page table pages are allocated from system memory with required size
and alignments.  The mapped pfns at page table levels are derived from a
real pfn representing a valid kernel text symbol.  This test gets called
via late_initcall().

This test gets built and run when CONFIG_DEBUG_VM_PGTABLE is selected.
Any architecture, which is willing to subscribe this test will need to
select ARCH_HAS_DEBUG_VM_PGTABLE.  For now this is limited to arc, arm64,
x86, s390 and powerpc platforms where the test is known to build and run
successfully Going forward, other architectures too can subscribe the test
after fixing any build or runtime problems with their page table helpers.

Folks interested in making sure that a given platform's page table helpers
conform to expected generic MM semantics should enable the above config
which will just trigger this test during boot.  Any non conformity here
will be reported as an warning which would need to be fixed.  This test
will help catch any changes to the agreed upon semantics expected from
generic MM and enable platforms to accommodate it thereafter.

[anshuman.khandual@arm.com: v17]
  Link: http://lkml.kernel.org/r/1587436495-22033-3-git-send-email-anshuman.khandual@arm.com
[anshuman.khandual@arm.com: v18]
  Link: http://lkml.kernel.org/r/1588564865-31160-3-git-send-email-anshuman.khandual@arm.com
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>	[s390]
Tested-by: Christophe Leroy <christophe.leroy@c-s.fr>	[ppc32]
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Link: http://lkml.kernel.org/r/1583919272-24178-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04 19:06:21 -07:00
5ff3b30ab5 kcov: collect coverage from interrupts
This change extends kcov remote coverage support to allow collecting
coverage from soft interrupts in addition to kernel background threads.

To collect coverage from code that is executed in softirq context, a part
of that code has to be annotated with kcov_remote_start/stop() in a
similar way as how it is done for global kernel background threads.  Then
the handle used for the annotations has to be passed to the
KCOV_REMOTE_ENABLE ioctl.

Internally this patch adjusts the __sanitizer_cov_trace_pc() compiler
inserted callback to not bail out when called from softirq context.
kcov_remote_start/stop() are updated to save/restore the current per task
kcov state in a per-cpu area (in case the softirq came when the kernel was
already collecting coverage in task context).  Coverage from softirqs is
collected into pre-allocated per-cpu areas, whose size is controlled by
the new CONFIG_KCOV_IRQ_AREA_SIZE.

[andreyknvl@google.com: turn current->kcov_softirq into unsigned int to fix objtool warning]
  Link: http://lkml.kernel.org/r/841c778aa3849c5cb8c3761f56b87ce653a88671.1585233617.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Marco Elver <elver@google.com>
Link: http://lkml.kernel.org/r/469bd385c431d050bc38a593296eff4baae50666.1584655448.git.andreyknvl@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04 19:06:20 -07:00
cfa3b8068b Merge tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma
Pull hmm updates from Jason Gunthorpe:
 "This series adds a selftest for hmm_range_fault() and several of the
  DEVICE_PRIVATE migration related actions, and another simplification
  for hmm_range_fault()'s API.

   - Simplify hmm_range_fault() with a simpler return code, no
     HMM_PFN_SPECIAL, and no customizable output PFN format

   - Add a selftest for hmm_range_fault() and DEVICE_PRIVATE related
     functionality"

* tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  MAINTAINERS: add HMM selftests
  mm/hmm/test: add selftests for HMM
  mm/hmm/test: add selftest driver for HMM
  mm/hmm: remove the customizable pfn format from hmm_range_fault
  mm/hmm: remove HMM_PFN_SPECIAL
  drm/amdgpu: remove dead code after hmm_range_fault()
  mm/hmm: make hmm_range_fault return 0 or -1
2020-06-02 14:05:27 -07:00
b23c4771ff Merge tag 'docs-5.8' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
 "A fair amount of stuff this time around, dominated by yet another
  massive set from Mauro toward the completion of the RST conversion. I
  *really* hope we are getting close to the end of this. Meanwhile,
  those patches reach pretty far afield to update document references
  around the tree; there should be no actual code changes there. There
  will be, alas, more of the usual trivial merge conflicts.

  Beyond that we have more translations, improvements to the sphinx
  scripting, a number of additions to the sysctl documentation, and lots
  of fixes"

* tag 'docs-5.8' of git://git.lwn.net/linux: (130 commits)
  Documentation: fixes to the maintainer-entry-profile template
  zswap: docs/vm: Fix typo accept_threshold_percent in zswap.rst
  tracing: Fix events.rst section numbering
  docs: acpi: fix old http link and improve document format
  docs: filesystems: add info about efivars content
  Documentation: LSM: Correct the basic LSM description
  mailmap: change email for Ricardo Ribalda
  docs: sysctl/kernel: document unaligned controls
  Documentation: admin-guide: update bug-hunting.rst
  docs: sysctl/kernel: document ngroups_max
  nvdimm: fixes to maintainter-entry-profile
  Documentation/features: Correct RISC-V kprobes support entry
  Documentation/features: Refresh the arch support status files
  Revert "docs: sysctl/kernel: document ngroups_max"
  docs: move locking-specific documents to locking/
  docs: move digsig docs to the security book
  docs: move the kref doc into the core-api book
  docs: add IRQ documentation at the core-api book
  docs: debugging-via-ohci1394.txt: add it to the core-api book
  docs: fix references for ipmi.rst file
  ...
2020-06-01 15:45:27 -07:00
5f215aab4e lib: Kconfig.debug: default KUNIT_* fragments to KUNIT_ALL_TESTS
This makes it easier to enable all KUnit fragments.

Adding 'if !KUNIT_ALL_TESTS' so individual tests can not be turned off.
Therefore if KUNIT_ALL_TESTS is enabled that will hide the prompt in
menuconfig.

Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-06-01 14:23:50 -06:00
69fc06f70f Merge tag 'objtool-core-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool updates from Ingo Molnar:
 "There are a lot of objtool changes in this cycle, all across the map:

   - Speed up objtool significantly, especially when there are large
     number of sections

   - Improve objtool's understanding of special instructions such as
     IRET, to reduce the number of annotations required

   - Implement 'noinstr' validation

   - Do baby steps for non-x86 objtool use

   - Simplify/fix retpoline decoding

   - Add vmlinux validation

   - Improve documentation

   - Fix various bugs and apply smaller cleanups"

* tag 'objtool-core-2020-06-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
  objtool: Enable compilation of objtool for all architectures
  objtool: Move struct objtool_file into arch-independent header
  objtool: Exit successfully when requesting help
  objtool: Add check_kcov_mode() to the uaccess safelist
  samples/ftrace: Fix asm function ELF annotations
  objtool: optimize add_dead_ends for split sections
  objtool: use gelf_getsymshndx to handle >64k sections
  objtool: Allow no-op CFI ops in alternatives
  x86/retpoline: Fix retpoline unwind
  x86: Change {JMP,CALL}_NOSPEC argument
  x86: Simplify retpoline declaration
  x86/speculation: Change FILL_RETURN_BUFFER to work with objtool
  objtool: Add support for intra-function calls
  objtool: Move the IRET hack into the arch decoder
  objtool: Remove INSN_STACK
  objtool: Make handle_insn_ops() unconditional
  objtool: Rework allocating stack_ops on decode
  objtool: UNWIND_HINT_RET_OFFSET should not check registers
  objtool: is_fentry_call() crashes if call has no destination
  x86,smap: Fix smap_{save,restore}() alternatives
  ...
2020-06-01 13:13:00 -07:00
10e68b02c8 Makefile: support compressed debug info
As debug information gets larger and larger, it helps significantly save
the size of vmlinux images to compress the information in the debug
information sections. Note: this debug info is typically split off from
the final compressed kernel image, which is why vmlinux is what's used
in conjunction with GDB. Minimizing the debug info size should have no
impact on boot times, or final compressed kernel image size.

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

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

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

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

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

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

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

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

Cc: Nick Clifton <nickc@redhat.com>
Suggested-by: David Blaikie <blaikie@google.com>
Reviewed-by: Fangrui Song <maskray@google.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-05-29 03:08:49 +09:00
b2ef9f5a5c mm/hmm/test: add selftest driver for HMM
This driver is for testing device private memory migration and devices
which use hmm_range_fault() to access system memory via device page tables.

Link: https://lore.kernel.org/r/20200422195028.3684-2-rcampbell@nvidia.com
Link: https://lore.kernel.org/r/20200516010424.2013-1-rcampbell@nvidia.com
Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Link: https://lore.kernel.org/r/20200509030225.14592-1-weiyongjun1@huawei.com
Link: https://lore.kernel.org/r/20200509030234.14747-1-weiyongjun1@huawei.com
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Link: https://lore.kernel.org/r/20200511183704.GA225608@mwanda
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2020-05-19 16:48:30 -03:00
a74e2a2264 docs: debugging-via-ohci1394.txt: add it to the core-api book
There is an special chapter inside the core-api book about
some debug infrastructure like tracepoints and debug objects.

It sounded to me that this is the best place to add a chapter
explaining how to use a FireWire controller to do remote
kernel debugging, as explained on this document.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/9b489d36d08ad89d3ad5aefef1f52a0715b29716.1588345503.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-05-15 11:59:17 -06:00
33d599f052 lib/test_linear_ranges: add a test for the 'linear_ranges'
Add a KUnit test for the linear_ranges helper.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Link: https://lore.kernel.org/r/311fea741bafdcd33804d3187c1642e24275e3e5.1588944082.git.matti.vaittinen@fi.rohmeurope.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-05-08 18:18:12 +01:00
6804c1afd7 kbuild/objtool: Add objtool-vmlinux.o pass
Now that objtool is capable of processing vmlinux.o and actually has
something useful to do there, (conditionally) add it to the final link
pass.

This will increase build time by a few seconds.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200416115119.287494491@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-04-22 10:53:51 +02:00
3b02a051d2 Merge tag 'v5.7-rc1' into locking/kcsan, to resolve conflicts and refresh
Resolve these conflicts:

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

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

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-04-13 09:44:39 +02:00
40fc7ad2c8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2020-04-10

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

We've added 13 non-merge commits during the last 7 day(s) which contain
a total of 13 files changed, 137 insertions(+), 43 deletions(-).

The main changes are:

1) JIT code emission fixes for riscv and arm32, from Luke Nelson and Xi Wang.

2) Disable vmlinux BTF info if GCC_PLUGIN_RANDSTRUCT is used, from Slava Bacherikov.

3) Fix oob write in AF_XDP when meta data is used, from Li RongQing.

4) Fix bpf_get_link_xdp_id() handling on single prog when flags are specified,
   from Andrey Ignatov.

5) Fix sk_assign() BPF helper for request sockets that can have sk_reuseport
   field uninitialized, from Joe Stringer.

6) Fix mprotect() test case for the BPF LSM, from KP Singh.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-09 17:39:22 -07:00
29b46fa3dc 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>
2020-04-07 10:43:44 -07:00
30428ef5d1 lib/test_lockup: test module to generate lockups
CONFIG_TEST_LOCKUP=m adds module "test_lockup" that helps to make sure
that watchdogs and lockup detectors are working properly.

Depending on module parameters test_lockup could emulate soft or hard
lockup, "hung task", hold arbitrary lock, allocate bunch of pages.

Also it could generate series of lockups with cooling-down periods, in
this way it could be used as "ping" for locks or page allocator.  Loop
checks signals between iteration thus could be stopped by ^C.

# modinfo test_lockup
...
parm:           time_secs:lockup time in seconds, default 0 (uint)
parm:           time_nsecs:nanoseconds part of lockup time, default 0 (uint)
parm:           cooldown_secs:cooldown time between iterations in seconds, default 0 (uint)
parm:           cooldown_nsecs:nanoseconds part of cooldown, default 0 (uint)
parm:           iterations:lockup iterations, default 1 (uint)
parm:           all_cpus:trigger lockup at all cpus at once (bool)
parm:           state:wait in 'R' running (default), 'D' uninterruptible, 'K' killable, 'S' interruptible state (charp)
parm:           use_hrtimer:use high-resolution timer for sleeping (bool)
parm:           iowait:account sleep time as iowait (bool)
parm:           lock_read:lock read-write locks for read (bool)
parm:           lock_single:acquire locks only at one cpu (bool)
parm:           reacquire_locks:release and reacquire locks/irq/preempt between iterations (bool)
parm:           touch_softlockup:touch soft-lockup watchdog between iterations (bool)
parm:           touch_hardlockup:touch hard-lockup watchdog between iterations (bool)
parm:           call_cond_resched:call cond_resched() between iterations (bool)
parm:           measure_lock_wait:measure lock wait time (bool)
parm:           lock_wait_threshold:print lock wait time longer than this in nanoseconds, default off (ulong)
parm:           disable_irq:disable interrupts: generate hard-lockups (bool)
parm:           disable_softirq:disable bottom-half irq handlers (bool)
parm:           disable_preempt:disable preemption: generate soft-lockups (bool)
parm:           lock_rcu:grab rcu_read_lock: generate rcu stalls (bool)
parm:           lock_mmap_sem:lock mm->mmap_sem: block procfs interfaces (bool)
parm:           lock_rwsem_ptr:lock rw_semaphore at address (ulong)
parm:           lock_mutex_ptr:lock mutex at address (ulong)
parm:           lock_spinlock_ptr:lock spinlock at address (ulong)
parm:           lock_rwlock_ptr:lock rwlock at address (ulong)
parm:           alloc_pages_nr:allocate and free pages under locks (uint)
parm:           alloc_pages_order:page order to allocate (uint)
parm:           alloc_pages_gfp:allocate pages with this gfp_mask, default GFP_KERNEL (uint)
parm:           alloc_pages_atomic:allocate pages with GFP_ATOMIC (bool)
parm:           reallocate_pages:free and allocate pages between iterations (bool)

Parameters for locking by address are unsafe and taints kernel. With
CONFIG_DEBUG_SPINLOCK=y they at least check magics for embedded spinlocks.

Examples:

task hang in D-state:
modprobe test_lockup time_secs=1 iterations=60 state=D

task hang in io-wait D-state:
modprobe test_lockup time_secs=1 iterations=60 state=D iowait

softlockup:
modprobe test_lockup time_secs=1 iterations=60 state=R

hardlockup:
modprobe test_lockup time_secs=1 iterations=60 state=R disable_irq

system-wide hardlockup:
modprobe test_lockup time_secs=1 iterations=60 state=R \
 disable_irq all_cpus

rcu stall:
modprobe test_lockup time_secs=1 iterations=60 state=R \
 lock_rcu touch_softlockup

lock mmap_sem / block procfs interfaces:
modprobe test_lockup time_secs=1 iterations=60 state=S lock_mmap_sem

lock tasklist_lock for read / block forks:
TASKLIST_LOCK=$(awk '$3 == "tasklist_lock" {print "0x"$1}' /proc/kallsyms)
modprobe test_lockup time_secs=1 iterations=60 state=R \
 disable_irq lock_read lock_rwlock_ptr=$TASKLIST_LOCK

lock namespace_sem / block vfs mount operations:
NAMESPACE_SEM=$(awk '$3 == "namespace_sem" {print "0x"$1}' /proc/kallsyms)
modprobe test_lockup time_secs=1 iterations=60 state=S \
 lock_rwsem_ptr=$NAMESPACE_SEM

lock cgroup mutex / block cgroup operations:
CGROUP_MUTEX=$(awk '$3 == "cgroup_mutex" {print "0x"$1}' /proc/kallsyms)
modprobe test_lockup time_secs=1 iterations=60 state=S \
 lock_mutex_ptr=$CGROUP_MUTEX

ping cgroup_mutex every second and measure maximum lock wait time:
modprobe test_lockup cooldown_secs=1 iterations=60 state=S \
 lock_mutex_ptr=$CGROUP_MUTEX reacquire_locks measure_lock_wait

[linux@roeck-us.net: rename disable_irq to fix build error]
  Link: http://lkml.kernel.org/r/20200317133614.23152-1-linux@roeck-us.net
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Dmitry Monakhov <dmtrmonakhov@yandex-team.ru
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Link: http://lkml.kernel.org/r/158132859146.2797.525923171323227836.stgit@buzz
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:42 -07:00
889b3c1245 compiler: remove CONFIG_OPTIMIZE_INLINING entirely
Commit ac7c3e4ff4 ("compiler: enable CONFIG_OPTIMIZE_INLINING
forcibly") made this always-on option. We released v5.4 and v5.5
including that commit.

Remove the CONFIG option and clean up the code now.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Miller <davem@davemloft.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200220110807.32534-2-masahiroy@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:42 -07:00
0ad5b053d4 Merge tag 'char-misc-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver updates from Greg KH:
 "Here is the big set of char/misc/other driver patches for 5.7-rc1.

  Lots of things in here, and it's later than expected due to some
  reverts to resolve some reported issues. All is now clean with no
  reported problems in linux-next.

  Included in here is:
   - interconnect updates
   - mei driver updates
   - uio updates
   - nvmem driver updates
   - soundwire updates
   - binderfs updates
   - coresight updates
   - habanalabs updates
   - mhi new bus type and core
   - extcon driver updates
   - some Kconfig cleanups
   - other small misc driver cleanups and updates

  As mentioned, all have been in linux-next for a while, and with the
  last two reverts, all is calm and good"

* tag 'char-misc-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (174 commits)
  Revert "driver core: platform: Initialize dma_parms for platform devices"
  Revert "amba: Initialize dma_parms for amba devices"
  amba: Initialize dma_parms for amba devices
  driver core: platform: Initialize dma_parms for platform devices
  bus: mhi: core: Drop the references to mhi_dev in mhi_destroy_device()
  bus: mhi: core: Initialize bhie field in mhi_cntrl for RDDM capture
  bus: mhi: core: Add support for reading MHI info from device
  misc: rtsx: set correct pcr_ops for rts522A
  speakup: misc: Use dynamic minor numbers for speakup devices
  mei: me: add cedar fork device ids
  coresight: do not use the BIT() macro in the UAPI header
  Documentation: provide IBM contacts for embargoed hardware
  nvmem: core: remove nvmem_sysfs_get_groups()
  nvmem: core: use is_bin_visible for permissions
  nvmem: core: use device_register and device_unregister
  nvmem: core: add root_only member to nvmem device struct
  extcon: axp288: Add wakeup support
  extcon: Mark extcon_get_edev_name() function as exported symbol
  extcon: palmas: Hide error messages if gpio returns -EPROBE_DEFER
  dt-bindings: extcon: usbc-cros-ec: convert extcon-usbc-cros-ec.txt to yaml format
  ...
2020-04-03 13:22:40 -07:00
7d32e69310 kbuild, btf: Fix dependencies for DEBUG_INFO_BTF
Currently turning on DEBUG_INFO_SPLIT when DEBUG_INFO_BTF is also
enabled will produce invalid btf file, since gen_btf function in
link-vmlinux.sh script doesn't handle *.dwo files.

Enabling DEBUG_INFO_REDUCED will also produce invalid btf file,
and using GCC_PLUGIN_RANDSTRUCT with BTF makes no sense.

Fixes: e83b9f5544 ("kbuild: add ability to generate BTF type info for vmlinux")
Reported-by: Jann Horn <jannh@google.com>
Reported-by: Liu Yiding <liuyd.fnst@cn.fujitsu.com>
Signed-off-by: Slava Bacherikov <slava@bacher09.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: KP Singh <kpsingh@google.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200402204138.408021-1-slava@bacher09.org
2020-04-03 00:27:36 +02:00
1f944f976d Merge tag 'tty-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial updates from Greg KH:
 "Here is the big set of TTY / Serial patches for 5.7-rc1

  Lots of console fixups and reworking in here, serial core tweaks
  (doesn't that ever get old, why are we still creating new serial
  devices?), serial driver updates, line-protocol driver updates, and
  some vt cleanups and fixes included in here as well.

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

* tag 'tty-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (161 commits)
  serial: 8250: Optimize irq enable after console write
  serial: 8250: Fix rs485 delay after console write
  vt: vt_ioctl: fix use-after-free in vt_in_use()
  vt: vt_ioctl: fix VT_DISALLOCATE freeing in-use virtual console
  tty: serial: make SERIAL_SPRD depend on COMMON_CLK
  tty: serial: fsl_lpuart: fix return value checking
  tty: serial: fsl_lpuart: move dma_request_chan()
  ARM: dts: tango4: Make /serial compatible with ns16550a
  ARM: dts: mmp*: Make the serial ports compatible with xscale-uart
  ARM: dts: mmp*: Fix serial port names
  ARM: dts: mmp2-brownstone: Don't redeclare phandle references
  ARM: dts: pxa*: Make the serial ports compatible with xscale-uart
  ARM: dts: pxa*: Fix serial port names
  ARM: dts: pxa*: Don't redeclare phandle references
  serial: omap: drop unused dt-bindings header
  serial: 8250: 8250_omap: Add DMA support for UARTs on K3 SoCs
  serial: 8250: 8250_omap: Work around errata causing spurious IRQs with DMA
  serial: 8250: 8250_omap: Extend driver data to pass FIFO trigger info
  serial: 8250: 8250_omap: Move locking out from __dma_rx_do_complete()
  serial: 8250: 8250_omap: Account for data in flight during DMA teardown
  ...
2020-03-31 16:18:55 -07:00
5b67fbfc32 Merge tag 'kbuild-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
 "Build system:

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

   - allow to run 'make dt_binding_check' without .config

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

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

   - Remove unused 'AS' variable

  Kconfig:

   - sanitize DEFCONFIG_LIST, and remove ARCH_DEFCONFIG from Kconfig
     files

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

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

  Misc:

   - add documentation on building the kernel with Clang/LLVM

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

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

   - various script and Makefile cleanups"

* tag 'kbuild-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (34 commits)
  Makefile: Update kselftest help information
  kbuild: deb-pkg: fix warning when CONFIG_DEBUG_INFO is unset
  kbuild: add outputmakefile to no-dot-config-targets
  kbuild: remove AS variable
  net: wan: wanxl: refactor the firmware rebuild rule
  net: wan: wanxl: use $(M68KCC) instead of $(M68KAS) for rebuilding firmware
  net: wan: wanxl: use allow to pass CROSS_COMPILE_M68k for rebuilding firmware
  kbuild: add comment about grouped target
  kbuild: add -Wall to KBUILD_HOSTCXXFLAGS
  kconfig: remove unused variable in qconf.cc
  sparc: revive __HAVE_ARCH_STRLEN for 32bit sparc
  kbuild: refactor Makefile.dtbinst more
  kbuild: compute the dtbs_install destination more simply
  Makefile: disallow data races on gcc-10 as well
  kconfig: make 'imply' obey the direct dependency
  kconfig: allow symbols implied by y to become m
  net: drop_monitor: use IS_REACHABLE() to guard net_dm_hw_report()
  modpost: return error if module is missing ns imports and MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS=n
  modpost: rework and consolidate logging interface
  kbuild: allow to run dt_binding_check without kernel configuration
  ...
2020-03-31 16:03:39 -07:00
9b82f05f86 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "The main changes in this cycle were:

  Kernel side changes:

   - A couple of x86/cpu cleanups and changes were grandfathered in due
     to patch dependencies. These clean up the set of CPU model/family
     matching macros with a consistent namespace and C99 initializer
     style.

   - A bunch of updates to various low level PMU drivers:
       * AMD Family 19h L3 uncore PMU
       * Intel Tiger Lake uncore support
       * misc fixes to LBR TOS sampling

   - optprobe fixes

   - perf/cgroup: optimize cgroup event sched-in processing

   - misc cleanups and fixes

  Tooling side changes are to:

   - perf {annotate,expr,record,report,stat,test}

   - perl scripting

   - libapi, libperf and libtraceevent

   - vendor events on Intel and S390, ARM cs-etm

   - Intel PT updates

   - Documentation changes and updates to core facilities

   - misc cleanups, fixes and other enhancements"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (89 commits)
  cpufreq/intel_pstate: Fix wrong macro conversion
  x86/cpu: Cleanup the now unused CPU match macros
  hwrng: via_rng: Convert to new X86 CPU match macros
  crypto: Convert to new CPU match macros
  ASoC: Intel: Convert to new X86 CPU match macros
  powercap/intel_rapl: Convert to new X86 CPU match macros
  PCI: intel-mid: Convert to new X86 CPU match macros
  mmc: sdhci-acpi: Convert to new X86 CPU match macros
  intel_idle: Convert to new X86 CPU match macros
  extcon: axp288: Convert to new X86 CPU match macros
  thermal: Convert to new X86 CPU match macros
  hwmon: Convert to new X86 CPU match macros
  platform/x86: Convert to new CPU match macros
  EDAC: Convert to new X86 CPU match macros
  cpufreq: Convert to new X86 CPU match macros
  ACPI: Convert to new X86 CPU match macros
  x86/platform: Convert to new CPU match macros
  x86/kernel: Convert to new CPU match macros
  x86/kvm: Convert to new CPU match macros
  x86/perf/events: Convert to new CPU match macros
  ...
2020-03-30 16:40:08 -07:00
de8f5e4f2d lockdep: Introduce wait-type checks
Extend lockdep to validate lock wait-type context.

The current wait-types are:

	LD_WAIT_FREE,		/* wait free, rcu etc.. */
	LD_WAIT_SPIN,		/* spin loops, raw_spinlock_t etc.. */
	LD_WAIT_CONFIG,		/* CONFIG_PREEMPT_LOCK, spinlock_t etc.. */
	LD_WAIT_SLEEP,		/* sleeping locks, mutex_t etc.. */

Where lockdep validates that the current lock (the one being acquired)
fits in the current wait-context (as generated by the held stack).

This ensures that there is no attempt to acquire mutexes while holding
spinlocks, to acquire spinlocks while holding raw_spinlocks and so on. In
other words, its a more fancy might_sleep().

Obviously RCU made the entire ordeal more complex than a simple single
value test because RCU can be acquired in (pretty much) any context and
while it presents a context to nested locks it is not the same as it
got acquired in.

Therefore its necessary to split the wait_type into two values, one
representing the acquire (outer) and one representing the nested context
(inner). For most 'normal' locks these two are the same.

[ To make static initialization easier we have the rule that:
  .outer == INV means .outer == .inner; because INV == 0. ]

It further means that its required to find the minimal .inner of the held
stack to compare against the outer of the new lock; because while 'normal'
RCU presents a CONFIG type to nested locks, if it is taken while already
holding a SPIN type it obviously doesn't relax the rules.

Below is an example output generated by the trivial test code:

  raw_spin_lock(&foo);
  spin_lock(&bar);
  spin_unlock(&bar);
  raw_spin_unlock(&foo);

 [ BUG: Invalid wait context ]
 -----------------------------
 swapper/0/1 is trying to lock:
 ffffc90000013f20 (&bar){....}-{3:3}, at: kernel_init+0xdb/0x187
 other info that might help us debug this:
 1 lock held by swapper/0/1:
  #0: ffffc90000013ee0 (&foo){+.+.}-{2:2}, at: kernel_init+0xd1/0x187

The way to read it is to look at the new -{n,m} part in the lock
description; -{3:3} for the attempted lock, and try and match that up to
the held locks, which in this case is the one: -{2,2}.

This tells that the acquiring lock requires a more relaxed environment than
presented by the lock stack.

Currently only the normal locks and RCU are converted, the rest of the
lockdep users defaults to .inner = INV which is ignored. More conversions
can be done when desired.

The check for spinlock_t nesting is not enabled by default. It's a separate
config option for now as there are known problems which are currently
addressed. The config option allows to identify these problems and to
verify that the solutions found are indeed solving them.

The config switch will be removed and the checks will permanently enabled
once the vast majority of issues has been addressed.

[ bigeasy: Move LD_WAIT_FREE,… out of CONFIG_LOCKDEP to avoid compile
	   failure with CONFIG_DEBUG_SPINLOCK + !CONFIG_LOCKDEP]
[ tglx: Add the config option ]

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200321113242.427089655@linutronix.de
2020-03-21 16:00:24 +01:00
a4654e9bde Merge branch 'x86/kdump' into locking/kcsan, to resolve conflicts
Conflicts:
	arch/x86/purgatory/Makefile

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-03-21 09:24:41 +01:00
d3394b3d51 serial/sysrq: Add a help-string for MAGIC_SYSRQ_SERIAL_SEQUENCE
To make it more obvious what almost everyone wants to set here.

Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Joe Perches <joe@perches.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Vasiliy Khoruzhick <vasilykh@arista.com>
Cc: linux-serial@vger.kernel.org
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Link: https://lore.kernel.org/r/20200306153156.579921-1-dima@arista.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 10:00:23 +01:00
68af43173d serial/sysrq: Add MAGIC_SYSRQ_SERIAL_SEQUENCE
Many embedded boards have a disconnected TTL level serial which can
generate some garbage that can lead to spurious false sysrq detects.

Currently, sysrq can be either completely disabled for serial console
or always disabled (with CONFIG_MAGIC_SYSRQ_SERIAL), since
commit 732dbf3a61 ("serial: do not accept sysrq characters via serial port")

At Arista, we have such boards that can generate BREAK and random
garbage. While disabling sysrq for serial console would solve
the problem with spurious false sysrq triggers, it's also desirable
to have a way to enable sysrq back.

As a measure of balance between on and off options, add
MAGIC_SYSRQ_SERIAL_SEQUENCE which is a string sequence that can enable
sysrq if it follows BREAK on a serial line. The longer the string - the
less likely it may be in the garbage.

Having the way to enable sysrq was beneficial to debug lockups with
a manual investigation in field and on the other side preventing false
sysrq detections.

Based-on-patch-by: Vasiliy Khoruzhick <vasilykh@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Link: https://lore.kernel.org/r/20200302175135.269397-3-dima@arista.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-07 09:52:02 +01:00
6e24628d78 lib: Introduce generic min-heap
Supports push, pop and converting an array into a heap. If the sense of
the compare function is inverted then it can provide a max-heap.

Based-on-work-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200214075133.181299-3-irogers@google.com
2020-03-06 11:56:59 +01:00
a83e4ca26a kbuild: remove cc-option switch from -Wframe-larger-than=
This CONFIG option was added by commit 35bb5b1e0e ("Add option to
enable -Wframe-larger-than= on gcc 4.4"). At that time, the cc-option
check was needed.

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

Remove the cc-option switch and redundant comments.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
2020-03-02 21:18:19 +09:00
239a5791ff dynamic_debug: allow to work if debugfs is disabled
With the realization that having debugfs enabled on "production" systems
is generally not a good idea, debugfs is being disabled from more and
more platforms over time.  However, the functionality of dynamic
debugging still is needed at times, and since it relies on debugfs for
its user api, having debugfs disabled also forces dynamic debug to be
disabled.

To get around this, also create the "control" file for dynamic_debug in
procfs.  This allows people turn on debugging as needed at runtime for
individual driverfs and subsystems.

Reported-by: many different companies
Cc: Jason Baron <jbaron@akamai.com>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200210211142.GB1373304@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-12 14:15:53 -08:00
08a3ef8f6b Merge tag 'linux-kselftest-5.6-rc1-kunit' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull Kselftest kunit updates from Shuah Khan:
 "This kunit update consists of:

   - Support for building kunit as a module from Alan Maguire

   - AppArmor KUnit tests for policy unpack from Mike Salvatore"

* tag 'linux-kselftest-5.6-rc1-kunit' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  kunit: building kunit as a module breaks allmodconfig
  kunit: update documentation to describe module-based build
  kunit: allow kunit to be loaded as a module
  kunit: remove timeout dependence on sysctl_hung_task_timeout_seconds
  kunit: allow kunit tests to be loaded as a module
  kunit: hide unexported try-catch interface in try-catch-impl.h
  kunit: move string-stream.h to lib/kunit
  apparmor: add AppArmor KUnit tests for policy unpack
2020-01-29 15:25:34 -08:00
c475c77d5b kunit: allow kunit tests to be loaded as a module
As tests are added to kunit, it will become less feasible to execute
all built tests together.  By supporting modular tests we provide
a simple way to do selective execution on a running system; specifying

CONFIG_KUNIT=y
CONFIG_KUNIT_EXAMPLE_TEST=m

...means we can simply "insmod example-test.ko" to run the tests.

To achieve this we need to do the following:

o export the required symbols in kunit
o string-stream tests utilize non-exported symbols so for now we skip
  building them when CONFIG_KUNIT_TEST=m.
o drivers/base/power/qos-test.c contains a few unexported interface
  references, namely freq_qos_read_value() and freq_constraints_init().
  Both of these could be potentially defined as static inline functions
  in include/linux/pm_qos.h, but for now we simply avoid supporting
  module build for that test suite.
o support a new way of declaring test suites.  Because a module cannot
  do multiple late_initcall()s, we provide a kunit_test_suites() macro
  to declare multiple suites within the same module at once.
o some test module names would have been too general ("test-test"
  and "example-test" for kunit tests, "inode-test" for ext4 tests);
  rename these as appropriate ("kunit-test", "kunit-example-test"
  and "ext4-inode-test" respectively).

Also define kunit_test_suite() via kunit_test_suites()
as callers in other trees may need the old definition.

Co-developed-by: Knut Omang <knut.omang@oracle.com>
Signed-off-by: Knut Omang <knut.omang@oracle.com>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Acked-by: Theodore Ts'o <tytso@mit.edu> # for ext4 bits
Acked-by: David Gow <davidgow@google.com> # For list-test
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-01-09 16:42:29 -07:00
28336be568 Merge tag 'v5.5-rc4' into locking/kcsan, to resolve conflicts
Conflicts:
	init/main.c
	lib/Kconfig.debug

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-30 08:10:51 +01:00
1e5f8a3085 Merge tag 'v5.5-rc3' into sched/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25 10:41:37 +01:00
045f6d7942 lib/Kconfig.debug: fix some messed up configurations
Some configuration items are messed up during conflict resolving.  For
example, STRICT_DEVMEM should not in testing menu, but kunit should.
This patch fixes all of them.

[akpm@linux-foundation.org: coding style fixes]
Link: http://lkml.kernel.org/r/20191209155653.7509-1-changbin.du@gmail.com
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-17 20:59:59 -08:00
9f47286924 sched/core: Use CONFIG_PREEMPTION
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT.
Both PREEMPT and PREEMPT_RT require the same functionality which today
depends on CONFIG_PREEMPT.

Let DEBUG_PREEMPT depend on CONFIG_PREEMPTION.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20191015191821.11479-33-bigeasy@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-08 14:37:37 +01:00
68d4b3dfca lib/: fix Kconfig indentation
Adjust indentation from spaces to tab (+optional two spaces) as in
coding style with command like:
	$ sed -e 's/^        /	/' -i */Kconfig

Link: http://lkml.kernel.org/r/20191120140140.19148-1-krzk@kernel.org
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-07 11:00:19 -08:00
ec29a5c197 kernel-hacking: move DEBUG_FS to 'Generic Kernel Debugging Instruments'
DEBUG_FS does not belong to 'Compile-time checks and compiler options'.

Link: http://lkml.kernel.org/r/20190909144453.3520-10-changbin.du@gmail.com
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-07 11:00:19 -08:00
2b05bb75d1 kernel-hacking: move DEBUG_BUGVERBOSE to 'printk and dmesg options'
I think DEBUG_BUGVERBOSE is a dmesg option which gives more debug info
to dmesg.

Link: http://lkml.kernel.org/r/20190909144453.3520-9-changbin.du@gmail.com
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-07 11:00:19 -08:00
ebebdd095d kernel-hacking: create a submenu for scheduler debugging options
Create a submenu 'Scheduler Debugging' for scheduler debugging options.

Link: http://lkml.kernel.org/r/20190909144453.3520-8-changbin.du@gmail.com
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-07 11:00:19 -08:00
dc9b96387e kernel-hacking: move SCHED_STACK_END_CHECK after DEBUG_STACK_USAGE
They are both memory debug options to debug kernel stack issues.

Link: http://lkml.kernel.org/r/20190909144453.3520-7-changbin.du@gmail.com
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-07 11:00:19 -08:00
f43a289df6 kernel-hacking: move Oops into 'Lockups and Hangs'
They are similar options so place them together.

Link: http://lkml.kernel.org/r/20190909144453.3520-6-changbin.du@gmail.com
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-07 11:00:19 -08:00
09a7495258 kernel-hacking: move kernel testing and coverage options to same submenu
Move error injection, coverage, testing options to a new top level
submenu 'Kernel Testing and Coverage'.  They are all for test purpose.

Link: http://lkml.kernel.org/r/20190909144453.3520-5-changbin.du@gmail.com
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-07 11:00:19 -08:00