Commit Graph

6240 Commits

Author SHA1 Message Date
Linus Torvalds
be9160a90d Kbuild fixes for v5.8
- fix -gz=zlib compiler option test for CONFIG_DEBUG_INFO_COMPRESSED
 
  - improve cc-option in scripts/Kbuild.include to clean up temp files
 
  - improve cc-option in scripts/Kconfig.include for more reliable compile
    option test
 
  - do not copy modules.builtin by 'make install' because it would break
    existing systems
 
  - use 'userprogs' syntax for watch_queue sample
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Merge tag 'kbuild-fixes-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - fix -gz=zlib compiler option test for CONFIG_DEBUG_INFO_COMPRESSED

 - improve cc-option in scripts/Kbuild.include to clean up temp files

 - improve cc-option in scripts/Kconfig.include for more reliable
   compile option test

 - do not copy modules.builtin by 'make install' because it would break
   existing systems

 - use 'userprogs' syntax for watch_queue sample

* tag 'kbuild-fixes-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  samples: watch_queue: build sample program for target architecture
  Revert "Makefile: install modules.builtin even if CONFIG_MODULES=n"
  scripts: Fix typo in headers_install.sh
  kconfig: unify cc-option and as-option
  kbuild: improve cc-option to clean up all temporary files
  Makefile: Improve compressed debug info support detection
2020-06-21 12:44:52 -07:00
Linus Torvalds
eede2b9b3f libnvdimm for 5.8-rc2
- Fix the visibility of the region 'align' attribute. The new unit tests
   for region alignment handling caught a corner case where the alignment
   cannot be specified if the region is converted from static to dynamic
   provisioning at runtime.
 
 - Add support for device health retrieval for the persistent memory
   supported by the papr_scm driver. This includes both the standard
   sysfs "health flags" that the nfit persistent memory driver publishes
   and a mechanism for the ndctl tool to retrieve a health-command payload.
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Merge tag 'libnvdimm-for-5.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dan Williams:
 "A feature (papr_scm health retrieval) and a fix (sysfs attribute
  visibility) for v5.8.

  Vaibhav explains in the merge commit below why missing v5.8 would be
  painful and I agreed to try a -rc2 pull because only cosmetics kept
  this out of -rc1 and his initial versions were posted in more than
  enough time for v5.8 consideration:

   'These patches are tied to specific features that were committed to
    customers in upcoming distros releases (RHEL and SLES) whose
    time-lines are tied to 5.8 kernel release.

    Being able to track the health of an nvdimm is critical for our
    customers that are running workloads leveraging papr-scm nvdimms.
    Missing the 5.8 kernel would mean missing the distro timelines and
    shifting forward the availability of this feature in distro kernels
    by at least 6 months'

  Summary:

   - Fix the visibility of the region 'align' attribute.

     The new unit tests for region alignment handling caught a corner
     case where the alignment cannot be specified if the region is
     converted from static to dynamic provisioning at runtime.

   - Add support for device health retrieval for the persistent memory
     supported by the papr_scm driver.

     This includes both the standard sysfs "health flags" that the nfit
     persistent memory driver publishes and a mechanism for the ndctl
     tool to retrieve a health-command payload"

* tag 'libnvdimm-for-5.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  nvdimm/region: always show the 'align' attribute
  powerpc/papr_scm: Implement support for PAPR_PDSM_HEALTH
  ndctl/papr_scm,uapi: Add support for PAPR nvdimm specific methods
  powerpc/papr_scm: Improve error logging and handling papr_scm_ndctl()
  powerpc/papr_scm: Fetch nvdimm health information from PHYP
  seq_buf: Export seq_buf_printf
  powerpc: Document details on H_SCM_HEALTH hcall
2020-06-20 13:13:21 -07:00
Linus Torvalds
5e857ce6ea Merge branch 'hch' (maccess patches from Christoph Hellwig)
Merge non-faulting memory access cleanups from Christoph Hellwig:
 "Andrew and I decided to drop the patches implementing your suggested
  rename of the probe_kernel_* and probe_user_* helpers from -mm as
  there were way to many conflicts.

  After -rc1 might be a good time for this as all the conflicts are
  resolved now"

This also adds a type safety checking patch on top of the renaming
series to make the subtle behavioral difference between 'get_user()' and
'get_kernel_nofault()' less potentially dangerous and surprising.

* emailed patches from Christoph Hellwig <hch@lst.de>:
  maccess: make get_kernel_nofault() check for minimal type compatibility
  maccess: rename probe_kernel_address to get_kernel_nofault
  maccess: rename probe_user_{read,write} to copy_{from,to}_user_nofault
  maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault
2020-06-18 12:35:51 -07:00
Christoph Hellwig
25f12ae45f maccess: rename probe_kernel_address to get_kernel_nofault
Better describe what this helper does, and match the naming of
copy_from_kernel_nofault.

Also switch the argument order around, so that it acts and looks
like get_user().

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-18 11:14:40 -07:00
Masahiro Yamada
4d0831e8a0 kconfig: unify cc-option and as-option
cc-option and as-option are almost the same; both pass the flag to
$(CC). The main difference is the cc-option stops before the assemble
stage (-S option) whereas as-option stops after (-c option).

I chose -S because it is slightly faster, but $(cc-option,-gz=zlib)
returns a wrong result (https://lkml.org/lkml/2020/6/9/1529).
It has been fixed by commit 7b16994437 ("Makefile: Improve compressed
debug info support detection"), but the assembler should always be
invoked for more reliable compiler option tests.

However, you cannot simply replace -S with -c because the following
code in lib/Kconfig.debug would break:

    depends on $(cc-option,-gsplit-dwarf)

The combination of -c and -gsplit-dwarf does not accept /dev/null as
output.

  $ cat /dev/null | gcc -gsplit-dwarf -S -x c - -o /dev/null
  $ echo $?
  0

  $ cat /dev/null | gcc -gsplit-dwarf -c -x c - -o /dev/null
  objcopy: Warning: '/dev/null' is not an ordinary file
  $ echo $?
  1

  $ cat /dev/null | gcc -gsplit-dwarf -c -x c - -o tmp.o
  $ echo $?
  0

There is another flag that creates an separate file based on the
object file path:

  $ cat /dev/null | gcc -ftest-coverage -c -x c - -o /dev/null
  <stdin>:1: error: cannot open /dev/null.gcno

So, we cannot use /dev/null to sink the output.

Align the cc-option implementation with scripts/Kbuild.include.

With -c option used in cc-option, as-option is unneeded.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
2020-06-17 10:38:42 +09:00
Vaibhav Jain
97c02c723b seq_buf: Export seq_buf_printf
'seq_buf' provides a very useful abstraction for writing to a string
buffer without needing to worry about it over-flowing. However even
though the API has been stable for couple of years now its still not
exported to kernel loadable modules limiting its usage.

Hence this patch proposes update to 'seq_buf.c' to mark
seq_buf_printf() which is part of the seq_buf API to be exported to
kernel loadable GPL modules. This symbol will be used in later parts
of this patch-set to simplify content creation for a sysfs attribute.

Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Piotr Maziarz <piotrx.maziarz@linux.intel.com>
Cc: Cezary Rojewski <cezary.rojewski@intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@alien8.de>
Link: https://lore.kernel.org/r/20200615124407.32596-3-vaibhav@linux.ibm.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2020-06-15 18:22:43 -07:00
Aditya Pakki
a6379f0ad6 test_objagg: Fix potential memory leak in error handling
In case of failure of check_expect_hints_stats(), the resources
allocated by objagg_hints_get should be freed. The patch fixes
this issue.

Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-15 13:32:11 -07:00
Arvind Sankar
7b16994437 Makefile: Improve compressed debug info support detection
Commit
  10e68b02c8 ("Makefile: support compressed debug info")
added support for compressed debug sections.

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

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

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

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

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

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

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

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-15 10:26:42 +09:00
Linus Torvalds
6adc19fd13 Kbuild updates for v5.8 (2nd)
- fix build rules in binderfs sample
 
  - fix build errors when Kbuild recurses to the top Makefile
 
  - covert '---help---' in Kconfig to 'help'
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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
Linus Torvalds
076f14be7f The X86 entry, exception and interrupt code rework
This all started about 6 month ago with the attempt to move the Posix CPU
 timer heavy lifting out of the timer interrupt code and just have lockless
 quick checks in that code path. Trivial 5 patches.
 
 This unearthed an inconsistency in the KVM handling of task work and the
 review requested to move all of this into generic code so other
 architectures can share.
 
 Valid request and solved with another 25 patches but those unearthed
 inconsistencies vs. RCU and instrumentation.
 
 Digging into this made it obvious that there are quite some inconsistencies
 vs. instrumentation in general. The int3 text poke handling in particular
 was completely unprotected and with the batched update of trace events even
 more likely to expose to endless int3 recursion.
 
 In parallel the RCU implications of instrumenting fragile entry code came
 up in several discussions.
 
 The conclusion of the X86 maintainer team was to go all the way and make
 the protection against any form of instrumentation of fragile and dangerous
 code pathes enforcable and verifiable by tooling.
 
 A first batch of preparatory work hit mainline with commit d5f744f9a2.
 
 The (almost) full solution introduced a new code section '.noinstr.text'
 into which all code which needs to be protected from instrumentation of all
 sorts goes into. Any call into instrumentable code out of this section has
 to be annotated. objtool has support to validate this. Kprobes now excludes
 this section fully which also prevents BPF from fiddling with it and all
 'noinstr' annotated functions also keep ftrace off. The section, kprobes
 and objtool changes are already merged.
 
 The major changes coming with this are:
 
     - Preparatory cleanups
 
     - Annotating of relevant functions to move them into the noinstr.text
       section or enforcing inlining by marking them __always_inline so the
       compiler cannot misplace or instrument them.
 
     - Splitting and simplifying the idtentry macro maze so that it is now
       clearly separated into simple exception entries and the more
       interesting ones which use interrupt stacks and have the paranoid
       handling vs. CR3 and GS.
 
     - Move quite some of the low level ASM functionality into C code:
 
        - enter_from and exit to user space handling. The ASM code now calls
          into C after doing the really necessary ASM handling and the return
 	 path goes back out without bells and whistels in ASM.
 
        - exception entry/exit got the equivivalent treatment
 
        - move all IRQ tracepoints from ASM to C so they can be placed as
          appropriate which is especially important for the int3 recursion
          issue.
 
     - Consolidate the declaration and definition of entry points between 32
       and 64 bit. They share a common header and macros now.
 
     - Remove the extra device interrupt entry maze and just use the regular
       exception entry code.
 
     - All ASM entry points except NMI are now generated from the shared header
       file and the corresponding macros in the 32 and 64 bit entry ASM.
 
     - The C code entry points are consolidated as well with the help of
       DEFINE_IDTENTRY*() macros. This allows to ensure at one central point
       that all corresponding entry points share the same semantics. The
       actual function body for most entry points is in an instrumentable
       and sane state.
 
       There are special macros for the more sensitive entry points,
       e.g. INT3 and of course the nasty paranoid #NMI, #MCE, #DB and #DF.
       They allow to put the whole entry instrumentation and RCU handling
       into safe places instead of the previous pray that it is correct
       approach.
 
     - The INT3 text poke handling is now completely isolated and the
       recursion issue banned. Aside of the entry rework this required other
       isolation work, e.g. the ability to force inline bsearch.
 
     - Prevent #DB on fragile entry code, entry relevant memory and disable
       it on NMI, #MC entry, which allowed to get rid of the nested #DB IST
       stack shifting hackery.
 
     - A few other cleanups and enhancements which have been made possible
       through this and already merged changes, e.g. consolidating and
       further restricting the IDT code so the IDT table becomes RO after
       init which removes yet another popular attack vector
 
     - About 680 lines of ASM maze are gone.
 
 There are a few open issues:
 
    - An escape out of the noinstr section in the MCE handler which needs
      some more thought but under the aspect that MCE is a complete
      trainwreck by design and the propability to survive it is low, this was
      not high on the priority list.
 
    - Paravirtualization
 
      When PV is enabled then objtool complains about a bunch of indirect
      calls out of the noinstr section. There are a few straight forward
      ways to fix this, but the other issues vs. general correctness were
      more pressing than parawitz.
 
    - KVM
 
      KVM is inconsistent as well. Patches have been posted, but they have
      not yet been commented on or picked up by the KVM folks.
 
    - IDLE
 
      Pretty much the same problems can be found in the low level idle code
      especially the parts where RCU stopped watching. This was beyond the
      scope of the more obvious and exposable problems and is on the todo
      list.
 
 The lesson learned from this brain melting exercise to morph the evolved
 code base into something which can be validated and understood is that once
 again the violation of the most important engineering principle
 "correctness first" has caused quite a few people to spend valuable time on
 problems which could have been avoided in the first place. The "features
 first" tinkering mindset really has to stop.
 
 With that I want to say thanks to everyone involved in contributing to this
 effort. Special thanks go to the following people (alphabetical order):
 
    Alexandre Chartre
    Andy Lutomirski
    Borislav Petkov
    Brian Gerst
    Frederic Weisbecker
    Josh Poimboeuf
    Juergen Gross
    Lai Jiangshan
    Macro Elver
    Paolo Bonzini
    Paul McKenney
    Peter Zijlstra
    Vitaly Kuznetsov
    Will Deacon
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Merge tag 'x86-entry-2020-06-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 entry updates from Thomas Gleixner:
 "The x86 entry, exception and interrupt code rework

  This all started about 6 month ago with the attempt to move the Posix
  CPU timer heavy lifting out of the timer interrupt code and just have
  lockless quick checks in that code path. Trivial 5 patches.

  This unearthed an inconsistency in the KVM handling of task work and
  the review requested to move all of this into generic code so other
  architectures can share.

  Valid request and solved with another 25 patches but those unearthed
  inconsistencies vs. RCU and instrumentation.

  Digging into this made it obvious that there are quite some
  inconsistencies vs. instrumentation in general. The int3 text poke
  handling in particular was completely unprotected and with the batched
  update of trace events even more likely to expose to endless int3
  recursion.

  In parallel the RCU implications of instrumenting fragile entry code
  came up in several discussions.

  The conclusion of the x86 maintainer team was to go all the way and
  make the protection against any form of instrumentation of fragile and
  dangerous code pathes enforcable and verifiable by tooling.

  A first batch of preparatory work hit mainline with commit
  d5f744f9a2 ("Pull x86 entry code updates from Thomas Gleixner")

  That (almost) full solution introduced a new code section
  '.noinstr.text' into which all code which needs to be protected from
  instrumentation of all sorts goes into. Any call into instrumentable
  code out of this section has to be annotated. objtool has support to
  validate this.

  Kprobes now excludes this section fully which also prevents BPF from
  fiddling with it and all 'noinstr' annotated functions also keep
  ftrace off. The section, kprobes and objtool changes are already
  merged.

  The major changes coming with this are:

    - Preparatory cleanups

    - Annotating of relevant functions to move them into the
      noinstr.text section or enforcing inlining by marking them
      __always_inline so the compiler cannot misplace or instrument
      them.

    - Splitting and simplifying the idtentry macro maze so that it is
      now clearly separated into simple exception entries and the more
      interesting ones which use interrupt stacks and have the paranoid
      handling vs. CR3 and GS.

    - Move quite some of the low level ASM functionality into C code:

       - enter_from and exit to user space handling. The ASM code now
         calls into C after doing the really necessary ASM handling and
         the return path goes back out without bells and whistels in
         ASM.

       - exception entry/exit got the equivivalent treatment

       - move all IRQ tracepoints from ASM to C so they can be placed as
         appropriate which is especially important for the int3
         recursion issue.

    - Consolidate the declaration and definition of entry points between
      32 and 64 bit. They share a common header and macros now.

    - Remove the extra device interrupt entry maze and just use the
      regular exception entry code.

    - All ASM entry points except NMI are now generated from the shared
      header file and the corresponding macros in the 32 and 64 bit
      entry ASM.

    - The C code entry points are consolidated as well with the help of
      DEFINE_IDTENTRY*() macros. This allows to ensure at one central
      point that all corresponding entry points share the same
      semantics. The actual function body for most entry points is in an
      instrumentable and sane state.

      There are special macros for the more sensitive entry points, e.g.
      INT3 and of course the nasty paranoid #NMI, #MCE, #DB and #DF.
      They allow to put the whole entry instrumentation and RCU handling
      into safe places instead of the previous pray that it is correct
      approach.

    - The INT3 text poke handling is now completely isolated and the
      recursion issue banned. Aside of the entry rework this required
      other isolation work, e.g. the ability to force inline bsearch.

    - Prevent #DB on fragile entry code, entry relevant memory and
      disable it on NMI, #MC entry, which allowed to get rid of the
      nested #DB IST stack shifting hackery.

    - A few other cleanups and enhancements which have been made
      possible through this and already merged changes, e.g.
      consolidating and further restricting the IDT code so the IDT
      table becomes RO after init which removes yet another popular
      attack vector

    - About 680 lines of ASM maze are gone.

  There are a few open issues:

   - An escape out of the noinstr section in the MCE handler which needs
     some more thought but under the aspect that MCE is a complete
     trainwreck by design and the propability to survive it is low, this
     was not high on the priority list.

   - Paravirtualization

     When PV is enabled then objtool complains about a bunch of indirect
     calls out of the noinstr section. There are a few straight forward
     ways to fix this, but the other issues vs. general correctness were
     more pressing than parawitz.

   - KVM

     KVM is inconsistent as well. Patches have been posted, but they
     have not yet been commented on or picked up by the KVM folks.

   - IDLE

     Pretty much the same problems can be found in the low level idle
     code especially the parts where RCU stopped watching. This was
     beyond the scope of the more obvious and exposable problems and is
     on the todo list.

  The lesson learned from this brain melting exercise to morph the
  evolved code base into something which can be validated and understood
  is that once again the violation of the most important engineering
  principle "correctness first" has caused quite a few people to spend
  valuable time on problems which could have been avoided in the first
  place. The "features first" tinkering mindset really has to stop.

  With that I want to say thanks to everyone involved in contributing to
  this effort. Special thanks go to the following people (alphabetical
  order): Alexandre Chartre, Andy Lutomirski, Borislav Petkov, Brian
  Gerst, Frederic Weisbecker, Josh Poimboeuf, Juergen Gross, Lai
  Jiangshan, Macro Elver, Paolo Bonzin,i Paul McKenney, Peter Zijlstra,
  Vitaly Kuznetsov, and Will Deacon"

* tag 'x86-entry-2020-06-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (142 commits)
  x86/entry: Force rcu_irq_enter() when in idle task
  x86/entry: Make NMI use IDTENTRY_RAW
  x86/entry: Treat BUG/WARN as NMI-like entries
  x86/entry: Unbreak __irqentry_text_start/end magic
  x86/entry: __always_inline CR2 for noinstr
  lockdep: __always_inline more for noinstr
  x86/entry: Re-order #DB handler to avoid *SAN instrumentation
  x86/entry: __always_inline arch_atomic_* for noinstr
  x86/entry: __always_inline irqflags for noinstr
  x86/entry: __always_inline debugreg for noinstr
  x86/idt: Consolidate idt functionality
  x86/idt: Cleanup trap_init()
  x86/idt: Use proper constants for table size
  x86/idt: Add comments about early #PF handling
  x86/idt: Mark init only functions __init
  x86/entry: Rename trace_hardirqs_off_prepare()
  x86/entry: Clarify irq_{enter,exit}_rcu()
  x86/entry: Remove DBn stacks
  x86/entry: Remove debug IDT frobbing
  x86/entry: Optimize local_db_save() for virt
  ...
2020-06-13 10:05:47 -07:00
Masahiro Yamada
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
Linus Torvalds
b791d1bdf9 The Kernel Concurrency Sanitizer (KCSAN)
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.
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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
Linus Torvalds
b1a6274994 Merge branch 'akpm' (patches from Andrew)
Pull updates from Andrew Morton:
 "A few fixes and stragglers.

  Subsystems affected by this patch series: mm/memory-failure, ocfs2,
  lib/lzo, misc"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  amdgpu: a NULL ->mm does not mean a thread is a kthread
  lib/lzo: fix ambiguous encoding bug in lzo-rle
  ocfs2: fix build failure when TCP/IP is disabled
  mm/memory-failure: send SIGBUS(BUS_MCEERR_AR) only to current thread
  mm/memory-failure: prioritize prctl(PR_MCE_KILL) over vm.memory_failure_early_kill
2020-06-11 18:18:50 -07:00
Dave Rodgman
b5265c813c lib/lzo: fix ambiguous encoding bug in lzo-rle
In some rare cases, for input data over 32 KB, lzo-rle could encode two
different inputs to the same compressed representation, so that
decompression is then ambiguous (i.e.  data may be corrupted - although
zram is not affected because it operates over 4 KB pages).

This modifies the compressor without changing the decompressor or the
bitstream format, such that:

 - there is no change to how data produced by the old compressor is
   decompressed

 - an old decompressor will correctly decode data from the updated
   compressor

 - performance and compression ratio are not affected

 - we avoid introducing a new bitstream format

In testing over 12.8M real-world files totalling 903 GB, three files
were affected by this bug.  I also constructed 37M semi-random 64 KB
files totalling 2.27 TB, and saw no affected files.  Finally I tested
over files constructed to contain each of the ~1024 possible bad input
sequences; for all of these cases, updated lzo-rle worked correctly.

There is no significant impact to performance or compression ratio.

Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Dave Rodgman <dave.rodgman@arm.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Markus F.X.J. Oberhumer <markus@oberhumer.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Chao Yu <yuchao0@huawei.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200507100203.29785-1-dave.rodgman@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-11 18:17:47 -07:00
Linus Torvalds
6a45a65888 A set of fixes and updates for x86:
- Unbreak paravirt VDSO clocks. While the VDSO code was moved into lib
     for sharing a subtle check for the validity of paravirt clocks got
     replaced. While the replacement works perfectly fine for bare metal as
     the update of the VDSO clock mode is synchronous, it fails for paravirt
     clocks because the hypervisor can invalidate them asynchronous. Bring
     it back as an optional function so it does not inflict this on
     architectures which are free of PV damage.
 
   - Fix the jiffies to jiffies64 mapping on 64bit so it does not trigger
     an ODR violation on newer compilers
 
   - Three fixes for the SSBD and *IB* speculation mitigation maze to ensure
     consistency, not disabling of some *IB* variants wrongly and to prevent
     a rogue cross process shutdown of SSBD. All marked for stable.
 
   - Add yet more CPU models to the splitlock detection capable list !@#%$!
 
   - Bring the pr_info() back which tells that TSC deadline timer is enabled.
 
   - Reboot quirk for MacBook6,1
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Merge tag 'x86-urgent-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull more x86 updates from Thomas Gleixner:
 "A set of fixes and updates for x86:

   - Unbreak paravirt VDSO clocks.

     While the VDSO code was moved into lib for sharing a subtle check
     for the validity of paravirt clocks got replaced. While the
     replacement works perfectly fine for bare metal as the update of
     the VDSO clock mode is synchronous, it fails for paravirt clocks
     because the hypervisor can invalidate them asynchronously.

     Bring it back as an optional function so it does not inflict this
     on architectures which are free of PV damage.

   - Fix the jiffies to jiffies64 mapping on 64bit so it does not
     trigger an ODR violation on newer compilers

   - Three fixes for the SSBD and *IB* speculation mitigation maze to
     ensure consistency, not disabling of some *IB* variants wrongly and
     to prevent a rogue cross process shutdown of SSBD. All marked for
     stable.

   - Add yet more CPU models to the splitlock detection capable list
     !@#%$!

   - Bring the pr_info() back which tells that TSC deadline timer is
     enabled.

   - Reboot quirk for MacBook6,1"

* tag 'x86-urgent-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/vdso: Unbreak paravirt VDSO clocks
  lib/vdso: Provide sanity check for cycles (again)
  clocksource: Remove obsolete ifdef
  x86_64: Fix jiffies ODR violation
  x86/speculation: PR_SPEC_FORCE_DISABLE enforcement for indirect branches.
  x86/speculation: Prevent rogue cross-process SSBD shutdown
  x86/speculation: Avoid force-disabling IBPB based on STIBP and enhanced IBRS.
  x86/cpu: Add Sapphire Rapids CPU model number
  x86/split_lock: Add Icelake microserver and Tigerlake CPU models
  x86/apic: Make TSC deadline timer detection message visible
  x86/reboot/quirks: Add MacBook6,1 reboot quirk
2020-06-11 15:54:31 -07:00
Linus Torvalds
92ac971219 A small fix for the VDSO code to force inline
__cvdso_clock_gettime_common() so the compiler can't generate horrible
 code.
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Merge tag 'timers-urgent-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer fix from Thomas Gleixner:
 "A small fix for the VDSO code to force inline
  __cvdso_clock_gettime_common() so the compiler
  can't generate horrible code"

* tag 'timers-urgent-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  lib/vdso: Force inlining of __cvdso_clock_gettime_common()
2020-06-11 15:36:28 -07:00
Linus Torvalds
623f6dc593 Merge branch 'akpm' (patches from Andrew)
Merge some more updates from Andrew Morton:

 - various hotfixes and minor things

 - hch's use_mm/unuse_mm clearnups

Subsystems affected by this patch series: mm/hugetlb, scripts, kcov,
lib, nilfs, checkpatch, lib, mm/debug, ocfs2, lib, misc.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  kernel: set USER_DS in kthread_use_mm
  kernel: better document the use_mm/unuse_mm API contract
  kernel: move use_mm/unuse_mm to kthread.c
  kernel: move use_mm/unuse_mm to kthread.c
  stacktrace: cleanup inconsistent variable type
  lib: test get_count_order/long in test_bitops.c
  mm: add comments on pglist_data zones
  ocfs2: fix spelling mistake and grammar
  mm/debug_vm_pgtable: fix kernel crash by checking for THP support
  lib: fix bitmap_parse() on 64-bit big endian archs
  checkpatch: correct check for kernel parameters doc
  nilfs2: fix null pointer dereference at nilfs_segctor_do_construct()
  lib/lz4/lz4_decompress.c: document deliberate use of `&'
  kcov: check kcov_softirq in kcov_remote_stop()
  scripts/spelling: add a few more typos
  khugepaged: selftests: fix timeout condition in wait_for_scan()
2020-06-11 13:25:53 -07:00
Marco Elver
0e1aa5b621 kcsan: Restrict supported compilers
The first version of Clang that supports -tsan-distinguish-volatile will
be able to support KCSAN. The first Clang release to do so, will be
Clang 11. This is due to satisfying all the following requirements:

1. Never emit calls to __tsan_func_{entry,exit}.

2. __no_kcsan functions should not call anything, not even
   kcsan_{enable,disable}_current(), when using __{READ,WRITE}_ONCE => Requires
   leaving them plain!

3. Support atomic_{read,set}*() with KCSAN, which rely on
   arch_atomic_{read,set}*() using __{READ,WRITE}_ONCE() => Because of
   #2, rely on Clang 11's -tsan-distinguish-volatile support. We will
   double-instrument atomic_{read,set}*(), but that's reasonable given
   it's still lower cost than the data_race() variant due to avoiding 2
   extra calls (kcsan_{en,dis}able_current() calls).

4. __always_inline functions inlined into __no_kcsan functions are never
   instrumented.

5. __always_inline functions inlined into instrumented functions are
   instrumented.

6. __no_kcsan_or_inline functions may be inlined into __no_kcsan functions =>
   Implies leaving 'noinline' off of __no_kcsan_or_inline.

7. Because of #6, __no_kcsan and __no_kcsan_or_inline functions should never be
   spuriously inlined into instrumented functions, causing the accesses of the
   __no_kcsan function to be instrumented.

Older versions of Clang do not satisfy #3. The latest GCC currently
doesn't support at least #1, #3, and #7.

Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/CANpmjNMTsY_8241bS7=XAfqvZHFLrVEkv_uM4aDUWE_kh3Rvbw@mail.gmail.com
Link: https://lkml.kernel.org/r/20200521142047.169334-7-elver@google.com
2020-06-11 20:04:00 +02:00
Arnd Bergmann
ea91a1d45d ubsan, kcsan: Don't combine sanitizer with kcov on clang
Clang does not allow -fsanitize-coverage=trace-{pc,cmp} together
with -fsanitize=bounds or with ubsan:

  clang: error: argument unused during compilation: '-fsanitize-coverage=trace-pc' [-Werror,-Wunused-command-line-argument]
  clang: error: argument unused during compilation: '-fsanitize-coverage=trace-cmp' [-Werror,-Wunused-command-line-argument]

To avoid the warning, check whether clang can handle this correctly or
disallow ubsan and kcsan when kcov is enabled.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marco Elver <elver@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://bugs.llvm.org/show_bug.cgi?id=45831
Link: https://lore.kernel.org/lkml/20200505142341.1096942-1-arnd@arndb.de
Link: https://lkml.kernel.org/r/20200521142047.169334-2-elver@google.com
2020-06-11 20:03:59 +02:00
Thomas Gleixner
37d1a04b13 Rebase locking/kcsan to locking/urgent
Merge the state of the locking kcsan branch before the read/write_once()
and the atomics modifications got merged.

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

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2020-06-11 20:02:46 +02:00
Peter Zijlstra
df65bba1dc lib/bsearch: Provide __always_inline variant
For code that needs the ultimate performance (it can inline the @cmp
function too) or simply needs to avoid calling external functions for
whatever reason, provide an __always_inline variant of bsearch().

[ tglx: Renamed to __inline_bsearch() as suggested by Andy ]

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505135313.624443814@linutronix.de
2020-06-11 15:14:53 +02:00
Thomas Gleixner
126f21f0e8 lib/smp_processor_id: Move it into noinstr section
That code is already not traceable. Move it into the noinstr section so the
objtool section validation does not trigger.

Annotate the warning code as "safe". While it might be not under all
circumstances, getting the information out is important enough.

Should this ever trigger from the sensitive code which is shielded against
instrumentation, e.g. low level entry, then the printk is the least of the
worries.

Addresses the objtool warnings:
 vmlinux.o: warning: objtool: context_tracking_recursion_enter()+0x7: call to __this_cpu_preempt_check() leaves .noinstr.text section
 vmlinux.o: warning: objtool: __context_tracking_exit()+0x17: call to __this_cpu_preempt_check() leaves .noinstr.text section
 vmlinux.o: warning: objtool: __context_tracking_enter()+0x2a: call to __this_cpu_preempt_check() leaves .noinstr.text section

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200505134340.902709267@linutronix.de
2020-06-11 15:14:36 +02:00
Wei Yang
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
Alexander Gordeev
81c4f4d924 lib: fix bitmap_parse() on 64-bit big endian archs
Commit 2d6261583b ("lib: rework bitmap_parse()") does not take into
account order of halfwords on 64-bit big endian architectures.  As
result (at least) Receive Packet Steering, IRQ affinity masks and
runtime kernel test "test_bitmap" get broken on s390.

[andriy.shevchenko@linux.intel.com: convert infinite while loop to a for loop]
  Link: http://lkml.kernel.org/r/20200609140535.87160-1-andriy.shevchenko@linux.intel.com

Fixes: 2d6261583b ("lib: rework bitmap_parse()")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Yury Norov <yury.norov@gmail.com>
Cc: Amritha Nambiar <amritha.nambiar@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: "Tobin C . Harding" <tobin@kernel.org>
Cc: Vineet Gupta <vineet.gupta1@synopsys.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/1591634471-17647-1-git-send-email-agordeev@linux.ibm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-10 19:14:17 -07:00
Joe Perches
e8ec04938c lib/lz4/lz4_decompress.c: document deliberate use of `&'
This operation was intentional, but tools such as smatch will warn that it
might not have been.

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Yann Collet <cyan@fb.com>
Cc: Vasily Averin <vvs@virtuozzo.com>
Cc: Gao Xiang <hsiangkao@aol.com>
Link: http://lkml.kernel.org/r/3bf931c6ea0cae3e23f3485801986859851b4f04.camel@perches.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-10 19:14:17 -07:00
Linus Torvalds
4152d146ee Merge branch 'rwonce/rework' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux
Pull READ/WRITE_ONCE rework from Will Deacon:
 "This the READ_ONCE rework I've been working on for a while, which
  bumps the minimum GCC version and improves code-gen on arm64 when
  stack protector is enabled"

[ Side note: I'm _really_ tempted to raise the minimum gcc version to
  4.9, so that we can just say that we require _Generic() support.

  That would allow us to more cleanly handle a lot of the cases where we
  depend on very complex macros with 'sizeof' or __builtin_choose_expr()
  with __builtin_types_compatible_p() etc.

  This branch has a workaround for sparse not handling _Generic(),
  either, but that was already fixed in the sparse development branch,
  so it's really just gcc-4.9 that we'd require.   - Linus ]

* 'rwonce/rework' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux:
  compiler_types.h: Use unoptimized __unqual_scalar_typeof for sparse
  compiler_types.h: Optimize __unqual_scalar_typeof compilation time
  compiler.h: Enforce that READ_ONCE_NOCHECK() access size is sizeof(long)
  compiler-types.h: Include naked type in __pick_integer_type() match
  READ_ONCE: Fix comment describing 2x32-bit atomicity
  gcov: Remove old GCC 3.4 support
  arm64: barrier: Use '__unqual_scalar_typeof' for acquire/release macros
  locking/barriers: Use '__unqual_scalar_typeof' for load-acquire macros
  READ_ONCE: Drop pointer qualifiers when reading from scalar types
  READ_ONCE: Enforce atomicity for {READ,WRITE}_ONCE() memory accesses
  READ_ONCE: Simplify implementations of {READ,WRITE}_ONCE()
  arm64: csum: Disable KASAN for do_csum()
  fault_inject: Don't rely on "return value" from WRITE_ONCE()
  net: tls: Avoid assigning 'const' pointer to non-const pointer
  netfilter: Avoid assigning 'const' pointer to non-const pointer
  compiler/gcc: Raise minimum GCC version for kernel builds to 4.8
2020-06-10 14:46:54 -07:00
Linus Torvalds
6f51ab9440 MTD core changes:
* partition parser: Support MTD names containing one or more colons.
 * mtdblock: clear cache_state to avoid writing to bad blocks repeatedly.
 
 Raw NAND core changes:
 
 * Stop using nand_release(), patched all drivers.
 * Give more information about the ECC weakness when not matching the
   chip's requirement.
 * MAINTAINERS updates.
 * Support emulated SLC mode on MLC NANDs.
 * Support "constrained" controllers, adapt the core and ONFI/JEDEC
   table parsing and Micron's code.
 * Take check_only into account.
 * Add an invalid ECC mode to discriminate with valid ones.
 * Return an enum from of_get_nand_ecc_algo().
 * Drop OOB_FIRST placement scheme.
 * Introduce nand_extract_bits().
 * Ensure a consistent bitflips numbering.
 * BCH lib:
   - Allow easy bit swapping.
   - Rework a little bit the exported function names.
 * Fix nand_gpio_waitrdy().
 * Propage CS selection to sub operations.
 * Add a NAND_NO_BBM_QUIRK flag.
 * Give the possibility to verify a read operation is supported.
 * Add a helper to check supported operations.
 * Avoid indirect access to ->data_buf().
 * Rename the use_bufpoi variables.
 * Fix comments about the use of bufpoi.
 * Rename a NAND chip option.
 * Reorder the nand_chip->options flags.
 * Translate obscure bitfields into readable macros.
 * Timings:
   - Fix default values.
   - Add mode information to the timings structure.
 
 Raw NAND controller driver changes:
 
 * Fixed many error paths.
 * Arasan
   - New driver
 * Au1550nd:
   - Various cleanups
   - Migration to ->exec_op()
 * brcmnand:
   - Misc cleanup.
   - Support v2.1-v2.2 controllers.
   - Remove unused including <linux/version.h>.
   - Correctly verify erased pages.
   - Fix Hamming OOB layout.
 * Cadence
   - Make cadence_nand_attach_chip static.
 * Cafe:
   - Set the NAND_NO_BBM_QUIRK flag
 * cmx270:
   - Remove this controller driver.
 * cs553x:
   - Misc cleanup
   - Migration to ->exec_op()
 * Davinci:
   - Misc cleanup.
   - Migration to ->exec_op()
 * Denali:
   - Add more delays before latching incoming data
 * Diskonchip:
    - Misc cleanup
    - Migration to ->exec_op()
 * Fsmc:
   - Change to non-atomic bit operations.
 * GPMI:
   - Use nand_extract_bits()
   - Fix runtime PM imbalance.
 * Ingenic:
   - Migration to exec_op()
   - Fix the RB gpio active-high property on qi, lb60
   - Make qi_lb60_ooblayout_ops static.
 * Marvell:
    - Misc cleanup and small fixes
 * Nandsim:
   - Fix the error paths, driver wide.
 * Omap_elm:
   - Fix runtime PM imbalance.
 * STM32_FMC2:
   - Misc cleanups (error cases, comments, timeout valus, cosmetic
     changes).
 
 SPI NOR core changes:
 
 * Add, update support and fix few flashes.
 * Prepare BFPT parsing for JESD216 rev D.
 * Kernel doc fixes.
 
 CFI changes:
 
 * Support the absence of protection registers for Intel CFI flashes.
 * Replace zero-length array with flexible-arrays.
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Merge tag 'mtd/for-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux

Pull MTD updates from Richard Weinberger:
 "MTD core changes:
   - partition parser: Support MTD names containing one or more colons.
   - mtdblock: clear cache_state to avoid writing to bad blocks
     repeatedly.

  Raw NAND core changes:
   - Stop using nand_release(), patched all drivers.
   - Give more information about the ECC weakness when not matching the
     chip's requirement.
   - MAINTAINERS updates.
   - Support emulated SLC mode on MLC NANDs.
   - Support "constrained" controllers, adapt the core and ONFI/JEDEC
     table parsing and Micron's code.
   - Take check_only into account.
   - Add an invalid ECC mode to discriminate with valid ones.
   - Return an enum from of_get_nand_ecc_algo().
   - Drop OOB_FIRST placement scheme.
   - Introduce nand_extract_bits().
   - Ensure a consistent bitflips numbering.
   - BCH lib:
      - Allow easy bit swapping.
      - Rework a little bit the exported function names.
   - Fix nand_gpio_waitrdy().
   - Propage CS selection to sub operations.
   - Add a NAND_NO_BBM_QUIRK flag.
   - Give the possibility to verify a read operation is supported.
   - Add a helper to check supported operations.
   - Avoid indirect access to ->data_buf().
   - Rename the use_bufpoi variables.
   - Fix comments about the use of bufpoi.
   - Rename a NAND chip option.
   - Reorder the nand_chip->options flags.
   - Translate obscure bitfields into readable macros.
   - Timings:
      - Fix default values.
      - Add mode information to the timings structure.

  Raw NAND controller driver changes:
   - Fixed many error paths.
   - Arasan
      - New driver
   - Au1550nd:
      - Various cleanups
      - Migration to ->exec_op()
   - brcmnand:
      - Misc cleanup.
      - Support v2.1-v2.2 controllers.
      - Remove unused including <linux/version.h>.
      - Correctly verify erased pages.
      - Fix Hamming OOB layout.
   - Cadence
      - Make cadence_nand_attach_chip static.
   - Cafe:
      - Set the NAND_NO_BBM_QUIRK flag
   - cmx270:
      - Remove this controller driver.
   - cs553x:
      - Misc cleanup
      - Migration to ->exec_op()
   - Davinci:
      - Misc cleanup.
      - Migration to ->exec_op()
   - Denali:
      - Add more delays before latching incoming data
   - Diskonchip:
      - Misc cleanup
      - Migration to ->exec_op()
   - Fsmc:
      - Change to non-atomic bit operations.
   - GPMI:
      - Use nand_extract_bits()
      - Fix runtime PM imbalance.
   - Ingenic:
      - Migration to exec_op()
      - Fix the RB gpio active-high property on qi, lb60
      - Make qi_lb60_ooblayout_ops static.
   - Marvell:
      - Misc cleanup and small fixes
   - Nandsim:
      - Fix the error paths, driver wide.
   - Omap_elm:
      - Fix runtime PM imbalance.
   - STM32_FMC2:
      - Misc cleanups (error cases, comments, timeout valus, cosmetic
        changes).

  SPI NOR core changes:
   - Add, update support and fix few flashes.
   - Prepare BFPT parsing for JESD216 rev D.
   - Kernel doc fixes.

  CFI changes:
   - Support the absence of protection registers for Intel CFI flashes.
   - Replace zero-length array with flexible-arrays"

* tag 'mtd/for-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux: (208 commits)
  mtd: clear cache_state to avoid writing to bad blocks repeatedly
  mtd: parser: cmdline: Support MTD names containing one or more colons
  mtd: physmap_of_gemini: remove defined but not used symbol 'syscon_match'
  mtd: rawnand: Add an invalid ECC mode to discriminate with valid ones
  mtd: rawnand: Return an enum from of_get_nand_ecc_algo()
  mtd: rawnand: Drop OOB_FIRST placement scheme
  mtd: rawnand: Avoid a typedef
  mtd: Fix typo in mtd_ooblayout_set_databytes() description
  mtd: rawnand: Stop using nand_release()
  mtd: rawnand: nandsim: Reorganize ns_cleanup_module()
  mtd: rawnand: nandsim: Rename a label in ns_init_module()
  mtd: rawnand: nandsim: Manage lists on error in ns_init_module()
  mtd: rawnand: nandsim: Fix the label pointing on nand_cleanup()
  mtd: rawnand: nandsim: Free erase_block_wear on error
  mtd: rawnand: nandsim: Use an additional label when freeing the nandsim object
  mtd: rawnand: nandsim: Stop using nand_release()
  mtd: rawnand: nandsim: Free the partition names in ns_free()
  mtd: rawnand: nandsim: Free the allocated device on error in ns_init()
  mtd: rawnand: nandsim: Free partition names on error in ns_init()
  mtd: rawnand: nandsim: Fix the two ns_alloc_device() error paths
  ...
2020-06-10 13:15:17 -07:00
Linus Torvalds
d1e521adad Tracing updates for 5.8:
No new features this release. Mostly clean ups, restructuring and
 documentation.
 
  - Have ftrace_bug() show ftrace errors before the WARN, as the WARN will
    reboot the box before the error messages are printed if panic_on_warn
    is set.
 
  - Have traceoff_on_warn disable tracing sooner (before prints)
 
  - Write a message to the trace buffer that its being disabled when
    disable_trace_on_warning() is set.
 
  - Separate out synthetic events from histogram code to let it be used by
    other parts of the kernel.
 
  - More documentation on histogram design.
 
  - Other small fixes and clean ups.
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Merge tag 'trace-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "No new features this release. Mostly clean ups, restructuring and
  documentation.

   - Have ftrace_bug() show ftrace errors before the WARN, as the WARN
     will reboot the box before the error messages are printed if
     panic_on_warn is set.

   - Have traceoff_on_warn disable tracing sooner (before prints)

   - Write a message to the trace buffer that its being disabled when
     disable_trace_on_warning() is set.

   - Separate out synthetic events from histogram code to let it be used
     by other parts of the kernel.

   - More documentation on histogram design.

   - Other small fixes and clean ups"

* tag 'trace-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Remove obsolete PREEMPTIRQ_EVENTS kconfig option
  tracing/doc: Fix ascii-art in histogram-design.rst
  tracing: Add a trace print when traceoff_on_warning is triggered
  ftrace,bug: Improve traceoff_on_warn
  selftests/ftrace: Distinguish between hist and synthetic event checks
  tracing: Move synthetic events to a separate file
  tracing: Fix events.rst section numbering
  tracing/doc: Fix typos in histogram-design.rst
  tracing: Add hist_debug trace event files for histogram debugging
  tracing: Add histogram-design document
  tracing: Check state.disabled in synth event trace functions
  tracing/probe: reverse arguments to list_add
  tools/bootconfig: Add a summary of test cases and return error
  ftrace: show debugging information when panic_on_warn set
2020-06-09 10:06:18 -07:00
Linus Torvalds
595a56ac1b linux-kselftest-kunit-5.8-rc1
This Kunit update for Linux 5.8-rc1 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.
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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
Linus Torvalds
fc2fb38c85 linux-kselftest-5.8-rc1
This Kselftest update for Linux 5.8-rc1 consists of:
 
 - Several fixes from Masami Hiramatsu to improve coverage for
   lib and sysctl tests.
 - Clean up to vdso test and a new test for getcpu() from Mark Brown.
 - Add new gen_tar selftests Makefile target generate selftest package
   running "make gen_tar" in selftests directory from Veronika Kabatova.
 - Other miscellaneous fixes to timens, exec, tpm2 tests.
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Merge tag 'linux-kselftest-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull kselftest updates from Shuah Khan:
 "This consists of:

   - Several fixes from Masami Hiramatsu to improve coverage for lib and
     sysctl tests.

   - Clean up to vdso test and a new test for getcpu() from Mark Brown.

   - Add new gen_tar selftests Makefile target generate selftest package
     running "make gen_tar" in selftests directory from Veronika
     Kabatova.

   - Other miscellaneous fixes to timens, exec, tpm2 tests"

* tag 'linux-kselftest-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  selftests/sysctl: Make sysctl test driver as a module
  selftests/sysctl: Fix to load test_sysctl module
  lib: Make test_sysctl initialized as module
  lib: Make prime number generator independently selectable
  selftests/ftrace: Return unsupported if no error_log file
  selftests/ftrace: Use printf for backslash included command
  selftests/timens: handle a case when alarm clocks are not supported
  Kernel selftests: Add check if TPM devices are supported
  selftests: vdso: Add a selftest for vDSO getcpu()
  selftests: vdso: Use a header file to prototype parse_vdso API
  selftests: vdso: Rename vdso_test to vdso_test_gettimeofday
  selftests/exec: Verify execve of non-regular files fail
  selftests: introduce gen_tar Makefile target
2020-06-09 10:03:12 -07:00
Michel Lespinasse
c1e8d7c6a7 mmap locking API: convert mmap_sem comments
Convert comments that reference mmap_sem to reference mmap_lock instead.

[akpm@linux-foundation.org: fix up linux-next leftovers]
[akpm@linux-foundation.org: s/lockaphore/lock/, per Vlastimil]
[akpm@linux-foundation.org: more linux-next fixups, per Michel]

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-13-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Michel Lespinasse
89154dd531 mmap locking API: convert mmap_sem call sites missed by coccinelle
Convert the last few remaining mmap_sem rwsem calls to use the new mmap
locking API.  These were missed by coccinelle for some reason (I think
coccinelle does not support some of the preprocessor constructs in these
files ?)

[akpm@linux-foundation.org: convert linux-next leftovers]
[akpm@linux-foundation.org: more linux-next leftovers]
[akpm@linux-foundation.org: more linux-next leftovers]

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-6-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Michel Lespinasse
d8ed45c5dc mmap locking API: use coccinelle to convert mmap_sem rwsem call sites
This change converts the existing mmap_sem rwsem calls to use the new mmap
locking API instead.

The change is generated using coccinelle with the following rule:

// spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir .

@@
expression mm;
@@
(
-init_rwsem
+mmap_init_lock
|
-down_write
+mmap_write_lock
|
-down_write_killable
+mmap_write_lock_killable
|
-down_write_trylock
+mmap_write_trylock
|
-up_write
+mmap_write_unlock
|
-downgrade_write
+mmap_write_downgrade
|
-down_read
+mmap_read_lock
|
-down_read_killable
+mmap_read_lock_killable
|
-down_read_trylock
+mmap_read_trylock
|
-up_read
+mmap_read_unlock
)
-(&mm->mmap_sem)
+(mm)

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Mike Rapoport
e31cf2f4ca mm: don't include asm/pgtable.h if linux/mm.h is already included
Patch series "mm: consolidate definitions of page table accessors", v2.

The low level page table accessors (pXY_index(), pXY_offset()) are
duplicated across all architectures and sometimes more than once.  For
instance, we have 31 definition of pgd_offset() for 25 supported
architectures.

Most of these definitions are actually identical and typically it boils
down to, e.g.

static inline unsigned long pmd_index(unsigned long address)
{
        return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1);
}

static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address)
{
        return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(address);
}

These definitions can be shared among 90% of the arches provided
XYZ_SHIFT, PTRS_PER_XYZ and xyz_page_vaddr() are defined.

For architectures that really need a custom version there is always
possibility to override the generic version with the usual ifdefs magic.

These patches introduce include/linux/pgtable.h that replaces
include/asm-generic/pgtable.h and add the definitions of the page table
accessors to the new header.

This patch (of 12):

The linux/mm.h header includes <asm/pgtable.h> to allow inlining of the
functions involving page table manipulations, e.g.  pte_alloc() and
pmd_alloc().  So, there is no point to explicitly include <asm/pgtable.h>
in the files that include <linux/mm.h>.

The include statements in such cases are remove with a simple loop:

	for f in $(git grep -l "include <linux/mm.h>") ; do
		sed -i -e '/include <asm\/pgtable.h>/ d' $f
	done

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-1-rppt@kernel.org
Link: http://lkml.kernel.org/r/20200514170327.31389-2-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Dmitry Safonov
9cb8f069de kernel: rename show_stack_loglvl() => show_stack()
Now the last users of show_stack() got converted to use an explicit log
level, show_stack_loglvl() can drop it's redundant suffix and become once
again well known show_stack().

Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200418201944.482088-51-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Dmitry Safonov
fe1993a001 kernel: use show_stack_loglvl()
Align the last users of show_stack() by KERN_DEFAULT as the surrounding
headers/messages.

Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200418201944.482088-50-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Thomas Gleixner
72ce778007 lib/vdso: Provide sanity check for cycles (again)
The original x86 VDSO implementation checked for the validity of the clock
source read by testing whether the returned signed cycles value is less
than zero. This check was also used by the vdso read function to signal
that the current selected clocksource is not VDSO capable.

During the rework of the VDSO code the check was removed and replaced with
a check for the clocksource mode being != NONE.

This turned out to be a mistake because the check is necessary for paravirt
and hyperv clock sources. The reason is that these clock sources have their
own internal sequence counter to validate the clocksource at the point of
reading it. This is necessary because the hypervisor can invalidate the
clocksource asynchronously so a check during the VDSO data update is not
sufficient. Having a separate indicator for the validity is slower than
just validating the cycles value. The check for it being negative turned
out to be the fastest implementation and safe as it would require an uptime
of ~73 years with a 4GHz counter frequency to result in a false positive.

Add an optional function to validate the cycles with a default
implementation which allows the compiler to optimize it out for
architectures which do not require it.

Fixes: 5d51bee725 ("clocksource: Add common vdso clock mode storage")
Reported-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200606221531.963970768@linutronix.de
2020-06-09 16:36:48 +02:00
Linus Torvalds
20b0d06722 Merge branch 'akpm' (patches from Andrew)
Merge still more updates from Andrew Morton:
 "Various trees. Mainly those parts of MM whose linux-next dependents
  are now merged. I'm still sitting on ~160 patches which await merges
  from -next.

  Subsystems affected by this patch series: mm/proc, ipc, dynamic-debug,
  panic, lib, sysctl, mm/gup, mm/pagemap"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (52 commits)
  doc: cgroup: update note about conditions when oom killer is invoked
  module: move the set_fs hack for flush_icache_range to m68k
  nommu: use flush_icache_user_range in brk and mmap
  binfmt_flat: use flush_icache_user_range
  exec: use flush_icache_user_range in read_code
  exec: only build read_code when needed
  m68k: implement flush_icache_user_range
  arm: rename flush_cache_user_range to flush_icache_user_range
  xtensa: implement flush_icache_user_range
  sh: implement flush_icache_user_range
  asm-generic: add a flush_icache_user_range stub
  mm: rename flush_icache_user_range to flush_icache_user_page
  arm,sparc,unicore32: remove flush_icache_user_range
  riscv: use asm-generic/cacheflush.h
  powerpc: use asm-generic/cacheflush.h
  openrisc: use asm-generic/cacheflush.h
  m68knommu: use asm-generic/cacheflush.h
  microblaze: use asm-generic/cacheflush.h
  ia64: use asm-generic/cacheflush.h
  hexagon: use asm-generic/cacheflush.h
  ...
2020-06-08 11:11:38 -07:00
Vlastimil Babka
4f2f682d89 lib/test_sysctl: support testing of sysctl. boot parameter
Testing is done by a new parameter debug.test_sysctl.boot_int which
defaults to 0 and it's expected that the tester passes a boot parameter
that sets it to 1.  The test checks if it's set to 1.

To distinguish true failure from parameter not being set, the test
checks /proc/cmdline for the expected parameter, and whether test_sysctl
is built-in and not a module.

[vbabka@suse.cz: skip the new test if boot_int sysctl is not present]
  Link: http://lkml.kernel.org/r/305af605-1e60-cf84-fada-6ce1ca37c102@suse.cz

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Guilherme G . Piccoli" <gpiccoli@canonical.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Ivan Teterevkov <ivan.teterevkov@nutanix.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200427180433.7029-6-vbabka@suse.cz
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-08 11:05:56 -07:00
Orson Zhai
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
Linus Torvalds
af7b480103 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:

 - Fix the build with certain Kconfig combinations for the Chelsio
   inline TLS device, from Rohit Maheshwar and Vinay Kumar Yadavi.

 - Fix leak in genetlink, from Cong Lang.

 - Fix out of bounds packet header accesses in seg6, from Ahmed
   Abdelsalam.

 - Two XDP fixes in the ENA driver, from Sameeh Jubran

 - Use rwsem in device rename instead of a seqcount because this code
   can sleep, from Ahmed S. Darwish.

 - Fix WoL regressions in r8169, from Heiner Kallweit.

 - Fix qed crashes in kdump mode, from Alok Prasad.

 - Fix the callbacks used for certain thermal zones in mlxsw, from Vadim
   Pasternak.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (35 commits)
  net: dsa: lantiq_gswip: fix and improve the unsupported interface error
  mlxsw: core: Use different get_trend() callbacks for different thermal zones
  net: dp83869: Reset return variable if PHY strap is read
  rhashtable: Drop raw RCU deref in nested_table_free
  cxgb4: Use kfree() instead kvfree() where appropriate
  net: qed: fixes crash while running driver in kdump kernel
  vsock/vmci: make vmci_vsock_transport_cb() static
  net: ethtool: Fix comment mentioning typo in IS_ENABLED()
  net: phy: mscc: fix Serdes configuration in vsc8584_config_init
  net: mscc: Fix OF_MDIO config check
  net: marvell: Fix OF_MDIO config check
  net: dp83867: Fix OF_MDIO config check
  net: dp83869: Fix OF_MDIO config check
  net: ethernet: mvneta: fix MVNETA_SKB_HEADROOM alignment
  ethtool: linkinfo: remove an unnecessary NULL check
  net/xdp: use shift instead of 64 bit division
  crypto/chtls:Fix compile error when CONFIG_IPV6 is disabled
  inet_connection_sock: clear inet_num out of destroy helper
  yam: fix possible memory leak in yam_init_driver
  lan743x: Use correct MAC_CR configuration for 1 GBit speed
  ...
2020-06-07 17:27:45 -07:00
Linus Torvalds
f558b8364e Driver core patches for 5.8-rc1
Here is the set of driver core patches for 5.8-rc1.
 
 Not all that huge this release, just a number of small fixes and
 updates:
 	- software node fixes
 	- kobject now sends KOBJ_REMOVE when it is removed from sysfs,
 	  not when it is removed from memory (which could come much
 	  later)
 	- device link additions and fixes based on testing on more
 	  devices
 	- firmware core cleanups
 	- other minor changes, full details in the shortlog
 
 All have been in linux-next for a while with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the set of driver core patches for 5.8-rc1.

  Not all that huge this release, just a number of small fixes and
  updates:

   - software node fixes

   - kobject now sends KOBJ_REMOVE when it is removed from sysfs, not
     when it is removed from memory (which could come much later)

   - device link additions and fixes based on testing on more devices

   - firmware core cleanups

   - other minor changes, full details in the shortlog

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

* tag 'driver-core-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (23 commits)
  driver core: Update device link status correctly for SYNC_STATE_ONLY links
  firmware_loader: change enum fw_opt to u32
  software node: implement software_node_unregister()
  kobject: send KOBJ_REMOVE uevent when the object is removed from sysfs
  driver core: Remove unnecessary is_fwnode_dev variable in device_add()
  drivers property: When no children in primary, try secondary
  driver core: platform: Fix spelling errors in platform.c
  driver core: Remove check in driver_deferred_probe_force_trigger()
  of: platform: Batch fwnode parsing when adding all top level devices
  driver core: fw_devlink: Add support for batching fwnode parsing
  driver core: Look for waiting consumers only for a fwnode's primary device
  driver core: Move code to the right part of the file
  Revert "Revert "driver core: Set fw_devlink to "permissive" behavior by default""
  drivers: base: Fix NULL pointer exception in __platform_driver_probe() if a driver developer is foolish
  firmware_loader: move fw_fallback_config to a private kernel symbol namespace
  driver core: Add missing '\n' in log messages
  driver/base/soc: Use kobj_to_dev() API
  Add documentation on meaning of -EPROBE_DEFER
  driver core: platform: remove redundant assignment to variable ret
  debugfs: Use the correct style for SPDX License Identifier
  ...
2020-06-07 10:53:36 -07:00
Herbert Xu
4a3084aaa8 rhashtable: Drop raw RCU deref in nested_table_free
This patch replaces some unnecessary uses of rcu_dereference_raw
in the rhashtable code with rcu_dereference_protected.

The top-level nested table entry is only marked as RCU because it
shares the same type as the tree entries underneath it.  So it
doesn't need any RCU protection.

We also don't need RCU protection when we're freeing a nested RCU
table because by this stage we've long passed a memory barrier
when anyone could change the nested table.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-06 15:51:17 -07:00
Linus Torvalds
cff11abeca Kbuild updates for v5.8
- fix warnings in 'make clean' for ARCH=um, hexagon, h8300, unicore32
 
  - ensure to rebuild all objects when the compiler is upgraded
 
  - exclude system headers from dependency tracking and fixdep processing
 
  - fix potential bit-size mismatch between the kernel and BPF user-mode
    helper
 
  - add the new syntax 'userprogs' to build user-space programs for the
    target architecture (the same arch as the kernel)
 
  - compile user-space sample code under samples/ for the target arch
    instead of the host arch
 
  - make headers_install fail if a CONFIG option is leaked to user-space
 
  - sanitize the output format of scripts/checkstack.pl
 
  - handle ARM 'push' instruction in scripts/checkstack.pl
 
  - error out before modpost if a module name conflict is found
 
  - error out when multiple directories are passed to M= because this
    feature is broken for a long time
 
  - add CONFIG_DEBUG_INFO_COMPRESSED to support compressed debug info
 
  - a lot of cleanups of modpost
 
  - dump vmlinux symbols out into vmlinux.symvers, and reuse it in the
    second pass of modpost
 
  - do not run the second pass of modpost if nothing in modules is updated
 
  - install modules.builtin(.modinfo) by 'make install' as well as by
    'make modules_install' because it is useful even when CONFIG_MODULES=n
 
  - add new command line variables, GZIP, BZIP2, LZOP, LZMA, LZ4, and XZ
    to allow users to use alternatives such as pigz, pbzip2, etc.
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Merge tag 'kbuild-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

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

 - ensure to rebuild all objects when the compiler is upgraded

 - exclude system headers from dependency tracking and fixdep processing

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

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

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

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

 - sanitize the output format of scripts/checkstack.pl

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

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

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

 - add CONFIG_DEBUG_INFO_COMPRESSED to support compressed debug info

 - a lot of cleanups of modpost

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

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

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

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

* tag 'kbuild-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (96 commits)
  kbuild: add variables for compression tools
  Makefile: install modules.builtin even if CONFIG_MODULES=n
  mksysmap: Fix the mismatch of '.L' symbols in System.map
  kbuild: doc: rename LDFLAGS to KBUILD_LDFLAGS
  modpost: change elf_info->size to size_t
  modpost: remove is_vmlinux() helper
  modpost: strip .o from modname before calling new_module()
  modpost: set have_vmlinux in new_module()
  modpost: remove mod->skip struct member
  modpost: add mod->is_vmlinux struct member
  modpost: remove is_vmlinux() call in check_for_{gpl_usage,unused}()
  modpost: remove mod->is_dot_o struct member
  modpost: move -d option in scripts/Makefile.modpost
  modpost: remove -s option
  modpost: remove get_next_text() and make {grab,release_}file static
  modpost: use read_text_file() and get_line() for reading text files
  modpost: avoid false-positive file open error
  modpost: fix potential mmap'ed file overrun in get_src_version()
  modpost: add read_text_file() and get_line() helpers
  modpost: do not call get_modinfo() for vmlinux(.o)
  ...
2020-06-06 12:00:25 -07:00
Linus Torvalds
828f3e18e1 ARM/SoC: drivers for v5.7
These are updates to SoC specific drivers that did not have
 another subsystem maintainer tree to go through for some
 reason:
 
 - Some bus and memory drivers for the MIPS P5600 based
   Baikal-T1 SoC that is getting added through the MIPS tree.
 
 - There are new soc_device identification drivers for TI K3,
   Qualcomm MSM8939
 
 - New reset controller drivers for NXP i.MX8MP, Renesas
   RZ/G1H, and Hisilicon hi6220
 
 - The SCMI firmware interface can now work across ARM SMC/HVC
   as a transport.
 
 - Mediatek platforms now use a new driver for their "MMSYS"
   hardware block that controls clocks and some other aspects
   in behalf of the media and gpu drivers.
 
 - Some Tegra processors have improved power management
   support, including getting woken up by the PMIC and cluster
   power down during idle.
 
 - A new v4l staging driver for Tegra is added.
 
 - Cleanups and minor bugfixes for TI, NXP, Hisilicon,
   Mediatek, and Tegra.
 
 Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Merge tag 'arm-drivers-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc

Pull ARM/SoC driver updates from Arnd Bergmann:
 "These are updates to SoC specific drivers that did not have another
  subsystem maintainer tree to go through for some reason:

   - Some bus and memory drivers for the MIPS P5600 based Baikal-T1 SoC
     that is getting added through the MIPS tree.

   - There are new soc_device identification drivers for TI K3, Qualcomm
     MSM8939

   - New reset controller drivers for NXP i.MX8MP, Renesas RZ/G1H, and
     Hisilicon hi6220

   - The SCMI firmware interface can now work across ARM SMC/HVC as a
     transport.

   - Mediatek platforms now use a new driver for their "MMSYS" hardware
     block that controls clocks and some other aspects in behalf of the
     media and gpu drivers.

   - Some Tegra processors have improved power management support,
     including getting woken up by the PMIC and cluster power down
     during idle.

   - A new v4l staging driver for Tegra is added.

   - Cleanups and minor bugfixes for TI, NXP, Hisilicon, Mediatek, and
     Tegra"

* tag 'arm-drivers-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (155 commits)
  clk: sprd: fix compile-testing
  bus: bt1-axi: Build the driver into the kernel
  bus: bt1-apb: Build the driver into the kernel
  bus: bt1-axi: Use sysfs_streq instead of strncmp
  bus: bt1-axi: Optimize the return points in the driver
  bus: bt1-apb: Use sysfs_streq instead of strncmp
  bus: bt1-apb: Use PTR_ERR_OR_ZERO to return from request-regs method
  bus: bt1-apb: Fix show/store callback identations
  bus: bt1-apb: Include linux/io.h
  dt-bindings: memory: Add Baikal-T1 L2-cache Control Block binding
  memory: Add Baikal-T1 L2-cache Control Block driver
  bus: Add Baikal-T1 APB-bus driver
  bus: Add Baikal-T1 AXI-bus driver
  dt-bindings: bus: Add Baikal-T1 APB-bus binding
  dt-bindings: bus: Add Baikal-T1 AXI-bus binding
  staging: tegra-video: fix V4L2 dependency
  tee: fix crypto select
  drivers: soc: ti: knav_qmss_queue: Make knav_gp_range_ops static
  soc: ti: add k3 platforms chipid module driver
  dt-bindings: soc: ti: add binding for k3 platforms chipid module
  ...
2020-06-04 19:56:20 -07:00
Arnd Bergmann
469cbd0161 lib/ubsan.c: fix gcc-10 warnings
The latest compiler expects slightly different function prototypes
for the ubsan helpers:

  lib/ubsan.c:192:6: error: conflicting types for built-in function '__ubsan_handle_add_overflow'; expected 'void(void *, void *, void *)' [-Werror=builtin-declaration-mismatch]
    192 | void __ubsan_handle_add_overflow(struct overflow_data *data,
        |      ^~~~~~~~~~~~~~~~~~~~~~~~~~~
  lib/ubsan.c:200:6: error: conflicting types for built-in function '__ubsan_handle_sub_overflow'; expected 'void(void *, void *, void *)' [-Werror=builtin-declaration-mismatch]
    200 | void __ubsan_handle_sub_overflow(struct overflow_data *data,
        |      ^~~~~~~~~~~~~~~~~~~~~~~~~~~
  lib/ubsan.c:207:6: error: conflicting types for built-in function '__ubsan_handle_mul_overflow'; expected 'void(void *, void *, void *)' [-Werror=builtin-declaration-mismatch]
    207 | void __ubsan_handle_mul_overflow(struct overflow_data *data,
        |      ^~~~~~~~~~~~~~~~~~~~~~~~~~~
  lib/ubsan.c:214:6: error: conflicting types for built-in function '__ubsan_handle_negate_overflow'; expected 'void(void *, void *)' [-Werror=builtin-declaration-mismatch]
    214 | void __ubsan_handle_negate_overflow(struct overflow_data *data,
        |      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  lib/ubsan.c:234:6: error: conflicting types for built-in function '__ubsan_handle_divrem_overflow'; expected 'void(void *, void *, void *)' [-Werror=builtin-declaration-mismatch]
    234 | void __ubsan_handle_divrem_overflow(struct overflow_data *data,
        |      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Change the Linux implementation to match these, using a local typed
pointer.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Julien Grall <julien.grall@arm.com>
Link: http://lkml.kernel.org/r/20200429185948.4189600-1-arnd@arndb.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04 19:06:28 -07:00
Jesse Brandeburg
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
Tan Hu
63d7f8167f lib/flex_proportions.c: cleanup __fprop_inc_percpu_max
If the given type has fraction smaller than max_frac/FPROP_FRAC_BASE, the
code could be modified to call __fprop_inc_percpu() directly and easier to
understand.  After this patch, fprop_reflect_period_percpu() will be
called twice, and quicky return on pl->period == p->period test, so it
would not result to significant downside of performance.

Thanks for Jan's guidance.

Signed-off-by: Tan Hu <tan.hu@zte.com.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: <xue.zhihong@zte.com.cn>
Cc: Yi Wang <wang.yi59@zte.com.cn>
Cc: <wang.liang82@zte.com.cn>
Link: http://lkml.kernel.org/r/1589004753-27554-1-git-send-email-tan.hu@zte.com.cn
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04 19:06:25 -07:00
Joe Perches
a818e526cb lib/percpu-refcount.c: use a more common logging style
Remove the trailing newline from the used-once pr_fmt and add it to the
single use of pr_<level> in this code to use a more common logging style.

Miscellanea:

o Use %lu in the pr_debug format and remove the unnecessary cast

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: http://lkml.kernel.org/r/47372467902a047c03b0fd29aab56e0c38d3f848.camel@perches.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04 19:06:25 -07:00
Jann Horn
acaab7335b lib/zlib: remove outdated and incorrect pre-increment optimization
The zlib inflate code has an old micro-optimization based on the
assumption that for pre-increment memory accesses, the compiler will
generate code that fits better into the processor's pipeline than what
would be generated for post-increment memory accesses.

This optimization was already removed in upstream zlib in 2016:
https://github.com/madler/zlib/commit/9aaec95e8211

This optimization causes UB according to C99, which says in section 6.5.6
"Additive operators": "If both the pointer operand and the result point to
elements of the same array object, or one past the last element of the
array object, the evaluation shall not produce an overflow; otherwise, the
behavior is undefined".

This UB is not only a theoretical concern, but can also cause trouble for
future work on compiler-based sanitizers.

According to the zlib commit, this optimization also is not optimal
anymore with modern compilers.

Replace uses of OFF, PUP and UP_UNALIGNED with their definitions in the
POSTINC case, and remove the macro definitions, just like in the upstream
patch.

Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Link: http://lkml.kernel.org/r/20200507123112.252723-1-jannh@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-04 19:06:25 -07:00