Commit Graph

905 Commits

Author SHA1 Message Date
Johannes Weiner 7b2489d37e psi: clarify the Kconfig text for the default-disable option
The current help text caused some confusion in online forums about
whether or not to default-enable or default-disable psi in vendor
kernels.  This is because it doesn't communicate the reason for why we
made this setting configurable in the first place: that the overhead is
non-zero in an artificial scheduler stress test.

Since this isn't representative of real workloads, and the effect was
not measurable in scheduler-heavy real world applications such as the
webservers and memcache installations at Facebook, it's fair to point
out that this is a pretty cautious option to select.

Link: http://lkml.kernel.org/r/20190129233617.16767-1-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-02-01 15:46:24 -08:00
Jonathan Neuschäfer 9807683384 init/Kconfig: fix grammar by moving a closing parenthesis
Link: http://lkml.kernel.org/r/20190129150813.15785-1-j.neuschaefer@gmx.net
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-02-01 15:46:23 -08:00
Paul Burton 16fd20aa98 kbuild: Disable LD_DEAD_CODE_DATA_ELIMINATION with ftrace & GCC <= 4.7
When building using GCC 4.7 or older, -ffunction-sections & the -pg flag
used by ftrace are incompatible. This causes warnings or build failures
(where -Werror applies) such as the following:

  arch/mips/generic/init.c:
    error: -ffunction-sections disabled; it makes profiling impossible

This used to be taken into account by the ordering of calls to cc-option
from within the top-level Makefile, which was introduced by commit
90ad4052e8 ("kbuild: avoid conflict between -ffunction-sections and
-pg on gcc-4.7"). Unfortunately this was broken when the
CONFIG_LD_DEAD_CODE_DATA_ELIMINATION cc-option check was moved to
Kconfig in commit e85d1d65cd ("kbuild: test dead code/data elimination
support in Kconfig"), because the flags used by this check no longer
include -pg.

Fix this by not allowing CONFIG_LD_DEAD_CODE_DATA_ELIMINATION to be
enabled at the same time as ftrace/CONFIG_FUNCTION_TRACER when building
using GCC 4.7 or older.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: e85d1d65cd ("kbuild: test dead code/data elimination support in Kconfig")
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: stable@vger.kernel.org # v4.19+
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-01-14 10:37:09 +09:00
Masahiro Yamada e9666d10a5 jump_label: move 'asm goto' support test to Kconfig
Currently, CONFIG_JUMP_LABEL just means "I _want_ to use jump label".

The jump label is controlled by HAVE_JUMP_LABEL, which is defined
like this:

  #if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL)
  # define HAVE_JUMP_LABEL
  #endif

We can improve this by testing 'asm goto' support in Kconfig, then
make JUMP_LABEL depend on CC_HAS_ASM_GOTO.

Ugly #ifdef HAVE_JUMP_LABEL will go away, and CONFIG_JUMP_LABEL will
match to the real kernel capability.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
2019-01-06 09:46:51 +09:00
Linus Torvalds 047ce6d380 audit/stable-4.21 PR 20181224
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Merge tag 'audit-pr-20181224' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit

Pull audit updates from Paul Moore:
 "In the finest of holiday of traditions, I have a number of gifts to
  share today. While most of them are re-gifts from others, unlike the
  typical re-gift, these are things you will want in and around your
  tree; I promise.

  This pull request is perhaps a bit larger than our typical PR, but
  most of it comes from Jan's rework of audit's fanotify code; a very
  welcome improvement. We ran this through our normal regression tests,
  as well as some newly created stress tests and everything looks good.

  Richard added a few patches, mostly cleaning up a few things and and
  shortening some of the audit records that we send to userspace; a
  change the userspace folks are quite happy about.

  Finally YueHaibing and I kick in a few patches to simplify things a
  bit and make the code less prone to errors.

  Lastly, I want to say thanks one more time to everyone who has
  contributed patches, testing, and code reviews for the audit subsystem
  over the past year. The project is what it is due to your help and
  contributions - thank you"

* tag 'audit-pr-20181224' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit: (22 commits)
  audit: remove duplicated include from audit.c
  audit: shorten PATH cap values when zero
  audit: use current whenever possible
  audit: minimize our use of audit_log_format()
  audit: remove WATCH and TREE config options
  audit: use session_info helper
  audit: localize audit_log_session_info prototype
  audit: Use 'mark' name for fsnotify_mark variables
  audit: Replace chunk attached to mark instead of replacing mark
  audit: Simplify locking around untag_chunk()
  audit: Drop all unused chunk nodes during deletion
  audit: Guarantee forward progress of chunk untagging
  audit: Allocate fsnotify mark independently of chunk
  audit: Provide helper for dropping mark's chunk reference
  audit: Remove pointless check in insert_hash()
  audit: Factor out chunk replacement code
  audit: Make hash table insertion safe against concurrent lookups
  audit: Embed key into chunk
  audit: Fix possible tagging failures
  audit: Fix possible spurious -ENOSPC error
  ...
2018-12-27 11:58:50 -08:00
Baruch Siach 428a1cb4ba psi: fix reference to kernel commandline enable
The kernel commandline parameter named in CONFIG_PSI_DEFAULT_DISABLED
help text contradicts the documentation in kernel-parameters.txt, and
the code.  Fix that.

Link: http://lkml.kernel.org/r/20181203213416.GA12627@cmpxchg.org
Fixes: e0c274472d ("psi: make disabling/enabling easier for vendor kernels")
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-14 15:05:45 -08:00
Johannes Weiner e0c274472d psi: make disabling/enabling easier for vendor kernels
Mel Gorman reports a hackbench regression with psi that would prohibit
shipping the suse kernel with it default-enabled, but he'd still like
users to be able to opt in at little to no cost to others.

With the current combination of CONFIG_PSI and the psi_disabled bool set
from the commandline, this is a challenge.  Do the following things to
make it easier:

1. Add a config option CONFIG_PSI_DEFAULT_DISABLED that allows distros
   to enable CONFIG_PSI in their kernel but leave the feature disabled
   unless a user requests it at boot-time.

   To avoid double negatives, rename psi_disabled= to psi=.

2. Make psi_disabled a static branch to eliminate any branch costs
   when the feature is disabled.

In terms of numbers before and after this patch, Mel says:

: The following is a comparision using CONFIG_PSI=n as a baseline against
: your patch and a vanilla kernel
:
:                          4.20.0-rc4             4.20.0-rc4             4.20.0-rc4
:                 kconfigdisable-v1r1                vanilla        psidisable-v1r1
: Amean     1       1.3100 (   0.00%)      1.3923 (  -6.28%)      1.3427 (  -2.49%)
: Amean     3       3.8860 (   0.00%)      4.1230 *  -6.10%*      3.8860 (  -0.00%)
: Amean     5       6.8847 (   0.00%)      8.0390 * -16.77%*      6.7727 (   1.63%)
: Amean     7       9.9310 (   0.00%)     10.8367 *  -9.12%*      9.9910 (  -0.60%)
: Amean     12     16.6577 (   0.00%)     18.2363 *  -9.48%*     17.1083 (  -2.71%)
: Amean     18     26.5133 (   0.00%)     27.8833 *  -5.17%*     25.7663 (   2.82%)
: Amean     24     34.3003 (   0.00%)     34.6830 (  -1.12%)     32.0450 (   6.58%)
: Amean     30     40.0063 (   0.00%)     40.5800 (  -1.43%)     41.5087 (  -3.76%)
: Amean     32     40.1407 (   0.00%)     41.2273 (  -2.71%)     39.9417 (   0.50%)
:
: It's showing that the vanilla kernel takes a hit (as the bisection
: indicated it would) and that disabling PSI by default is reasonably
: close in terms of performance for this particular workload on this
: particular machine so;

Link: http://lkml.kernel.org/r/20181127165329.GA29728@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Tested-by: Mel Gorman <mgorman@techsingularity.net>
Reported-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-11-30 14:56:14 -08:00
Richard Guy Briggs c8fc5d49c3 audit: remove WATCH and TREE config options
Remove the CONFIG_AUDIT_WATCH and CONFIG_AUDIT_TREE config options since
they are both dependent on CONFIG_AUDITSYSCALL and force
CONFIG_FSNOTIFY.

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-11-19 16:29:50 -05:00
Johannes Weiner 2ce7135adc psi: cgroup support
On a system that executes multiple cgrouped jobs and independent
workloads, we don't just care about the health of the overall system, but
also that of individual jobs, so that we can ensure individual job health,
fairness between jobs, or prioritize some jobs over others.

This patch implements pressure stall tracking for cgroups.  In kernels
with CONFIG_PSI=y, cgroup2 groups will have cpu.pressure, memory.pressure,
and io.pressure files that track aggregate pressure stall times for only
the tasks inside the cgroup.

Link: http://lkml.kernel.org/r/20180828172258.3185-10-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Daniel Drake <drake@endlessm.com>
Tested-by: Suren Baghdasaryan <surenb@google.com>
Cc: Christopher Lameter <cl@linux.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Weiner <jweiner@fb.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Enderborg <peter.enderborg@sony.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Vinayak Menon <vinmenon@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-26 16:26:32 -07:00
Johannes Weiner eb414681d5 psi: pressure stall information for CPU, memory, and IO
When systems are overcommitted and resources become contended, it's hard
to tell exactly the impact this has on workload productivity, or how close
the system is to lockups and OOM kills.  In particular, when machines work
multiple jobs concurrently, the impact of overcommit in terms of latency
and throughput on the individual job can be enormous.

In order to maximize hardware utilization without sacrificing individual
job health or risk complete machine lockups, this patch implements a way
to quantify resource pressure in the system.

A kernel built with CONFIG_PSI=y creates files in /proc/pressure/ that
expose the percentage of time the system is stalled on CPU, memory, or IO,
respectively.  Stall states are aggregate versions of the per-task delay
accounting delays:

       cpu: some tasks are runnable but not executing on a CPU
       memory: tasks are reclaiming, or waiting for swapin or thrashing cache
       io: tasks are waiting for io completions

These percentages of walltime can be thought of as pressure percentages,
and they give a general sense of system health and productivity loss
incurred by resource overcommit.  They can also indicate when the system
is approaching lockup scenarios and OOMs.

To do this, psi keeps track of the task states associated with each CPU
and samples the time they spend in stall states.  Every 2 seconds, the
samples are averaged across CPUs - weighted by the CPUs' non-idle time to
eliminate artifacts from unused CPUs - and translated into percentages of
walltime.  A running average of those percentages is maintained over 10s,
1m, and 5m periods (similar to the loadaverage).

[hannes@cmpxchg.org: doc fixlet, per Randy]
  Link: http://lkml.kernel.org/r/20180828205625.GA14030@cmpxchg.org
[hannes@cmpxchg.org: code optimization]
  Link: http://lkml.kernel.org/r/20180907175015.GA8479@cmpxchg.org
[hannes@cmpxchg.org: rename psi_clock() to psi_update_work(), per Peter]
  Link: http://lkml.kernel.org/r/20180907145404.GB11088@cmpxchg.org
[hannes@cmpxchg.org: fix build]
  Link: http://lkml.kernel.org/r/20180913014222.GA2370@cmpxchg.org
Link: http://lkml.kernel.org/r/20180828172258.3185-9-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Daniel Drake <drake@endlessm.com>
Tested-by: Suren Baghdasaryan <surenb@google.com>
Cc: Christopher Lameter <cl@linux.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Weiner <jweiner@fb.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Enderborg <peter.enderborg@sony.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vinayak Menon <vinmenon@codeaurora.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-26 16:26:32 -07:00
Vincent Guittot 11d4afd4ff sched/pelt: Fix warning and clean up IRQ PELT config
Create a config for enabling irq load tracking in the scheduler.
irq load tracking is useful only when irq or paravirtual time is
accounted but it's only possible with SMP for now.

Also use __maybe_unused to remove the compilation warning in
update_rq_clock_task() that has been introduced by:

  2e62c4743a ("sched/fair: Remove #ifdefs from scale_rt_capacity()")

Suggested-by: Ingo Molnar <mingo@redhat.com>
Reported-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Reported-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@alien8.de
Cc: dou_liyang@163.com
Fixes: 2e62c4743a ("sched/fair: Remove #ifdefs from scale_rt_capacity()")
Link: http://lkml.kernel.org/r/1537867062-27285-1-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-02 09:45:00 +02:00
Linus Torvalds 1bc276775d Kbuild updates for v4.19 (2nd)
- add build_{menu,n,g,x}config targets for compile-testing Kconfig
 
  - fix and improve recursive dependency detection in Kconfig
 
  - fix parallel building of menuconfig/nconfig
 
  - fix syntax error in clang-version.sh
 
  - suppress distracting log from syncconfig
 
  - remove obsolete "rpm" target
 
  - remove VMLINUX_SYMBOL(_STR) macro entirely
 
  - fix microblaze build with CONFIG_DYNAMIC_FTRACE
 
  - move compiler test for dead code/data elimination to Kconfig
 
  - rename well-known LDFLAGS variable to KBUILD_LDFLAGS
 
  - misc fixes and cleanups
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Merge tag 'kbuild-v4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull more Kbuild updates from Masahiro Yamada:

 - add build_{menu,n,g,x}config targets for compile-testing Kconfig

 - fix and improve recursive dependency detection in Kconfig

 - fix parallel building of menuconfig/nconfig

 - fix syntax error in clang-version.sh

 - suppress distracting log from syncconfig

 - remove obsolete "rpm" target

 - remove VMLINUX_SYMBOL(_STR) macro entirely

 - fix microblaze build with CONFIG_DYNAMIC_FTRACE

 - move compiler test for dead code/data elimination to Kconfig

 - rename well-known LDFLAGS variable to KBUILD_LDFLAGS

 - misc fixes and cleanups

* tag 'kbuild-v4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: rename LDFLAGS to KBUILD_LDFLAGS
  kbuild: pass LDFLAGS to recordmcount.pl
  kbuild: test dead code/data elimination support in Kconfig
  initramfs: move gen_initramfs_list.sh from scripts/ to usr/
  vmlinux.lds.h: remove stale <linux/export.h> include
  export.h: remove VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR()
  Coccinelle: remove pci_alloc_consistent semantic to detect in zalloc-simple.cocci
  kbuild: make sorting initramfs contents independent of locale
  kbuild: remove "rpm" target, which is alias of "rpm-pkg"
  kbuild: Fix LOADLIBES rename in Documentation/kbuild/makefiles.txt
  kconfig: suppress "configuration written to .config" for syncconfig
  kconfig: fix "Can't open ..." in parallel build
  kbuild: Add a space after `!` to prevent parsing as file pattern
  scripts: modpost: check memory allocation results
  kconfig: improve the recursive dependency report
  kconfig: report recursive dependency involving 'imply'
  kconfig: error out when seeing recursive dependency
  kconfig: add build-only configurator targets
  scripts/dtc: consolidate include path options in Makefile
2018-08-25 13:40:38 -07:00
Masahiro Yamada e85d1d65cd kbuild: test dead code/data elimination support in Kconfig
This config option should be enabled only when both the compiler and
the linker support necessary flags.  Add proper dependencies to Kconfig.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-08-24 08:10:00 +09:00
Adrian Reber 5cb366bb3a init/Kconfig: remove EXPERT from CHECKPOINT_RESTORE
The CHECKPOINT_RESTORE configuration option was introduced in 2012 and
combined with EXPERT.  CHECKPOINT_RESTORE is already enabled in many
distribution kernels and also part of the defconfigs of various
architectures.

To make it easier for distributions to enable CHECKPOINT_RESTORE this
removes EXPERT and moves the configuration option out of the EXPERT block.

Link: http://lkml.kernel.org/r/20180712130733.11510-1-adrian@lisas.de
Signed-off-by: Adrian Reber <adrian@lisas.de>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Acked-by: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22 10:52:51 -07:00
Randy Dunlap 3903bf940b init/Kconfig: fix its typos
Correct typos of "it's" to "its.

Link: http://lkml.kernel.org/r/0ac627b6-5527-55f4-0489-1631aa34fc11@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22 10:52:49 -07:00
Kirill Tkhai 84c07d11aa mm: introduce CONFIG_MEMCG_KMEM as combination of CONFIG_MEMCG && !CONFIG_SLOB
Introduce new config option, which is used to replace repeating
CONFIG_MEMCG && !CONFIG_SLOB pattern.  Next patches add a little more
memcg+kmem related code, so let's keep the defines more clearly.

Link: http://lkml.kernel.org/r/153063053670.1818.15013136946600481138.stgit@localhost.localdomain
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com>
Tested-by: Shakeel Butt <shakeelb@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Li RongQing <lirongqing@baidu.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matthias Kaehlcke <mka@chromium.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Sahitya Tummala <stummala@codeaurora.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-17 16:20:30 -07:00
Linus Torvalds fa1b5d09d0 Consolidation of Kconfig files by Christoph Hellwig.
Move the source statements of arch-independent Kconfig files instead of
 duplicating the includes in every arch/$(SRCARCH)/Kconfig.
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Merge tag 'kconfig-v4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kconfig consolidation from Masahiro Yamada:
 "Consolidation of Kconfig files by Christoph Hellwig.

  Move the source statements of arch-independent Kconfig files instead
  of duplicating the includes in every arch/$(SRCARCH)/Kconfig"

* tag 'kconfig-v4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kconfig: add a Memory Management options" menu
  kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt
  kconfig: use a menu in arch/Kconfig to reduce clutter
  kconfig: include kernel/Kconfig.preempt from init/Kconfig
  Kconfig: consolidate the "Kernel hacking" menu
  kconfig: include common Kconfig files from top-level Kconfig
  kconfig: remove duplicate SWAP symbol defintions
  um: create a proper drivers Kconfig
  um: cleanup Kconfig files
  um: stop abusing KBUILD_KCONFIG
2018-08-15 13:05:12 -07:00
Linus Torvalds 01f0e5cded Kconfig updates for v4.19
- show clearer error messages where pkg-config is needed, but not
   installed
 
 - rename SYMBOL_AUTO to SYMBOL_NO_WRITE to reflect its semantics
 
 - create all necessary directories by Kconfig tool itself instead
   of Makefile
 
 - update the .config unconditionally when syncconfig is invoked
 
 - use 'include' directive instead of '-include' where
   include/config/{auto,tristate}.conf is mandatory
 
 - do not try to update the .config when running install targets
 
 - add .DELETE_ON_ERROR to delete partially updated files
 
 - misc cleanups and fixes
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Merge tag 'kconfig-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kconfig updates from Masahiro Yamada:

 - show clearer error messages where pkg-config is needed, but not
   installed

 - rename SYMBOL_AUTO to SYMBOL_NO_WRITE to reflect its semantics

 - create all necessary directories by Kconfig tool itself instead of
   Makefile

 - update the .config unconditionally when syncconfig is invoked

 - use 'include' directive instead of '-include' where
   include/config/{auto,tristate}.conf is mandatory

 - do not try to update the .config when running install targets

 - add .DELETE_ON_ERROR to delete partially updated files

 - misc cleanups and fixes

* tag 'kconfig-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kconfig: remove P_ENV property type
  kconfig: remove unused sym_get_env_prop() function
  kconfig: fix the rule of mainmenu_stmt symbol
  init/Kconfig: Use short unix-style option instead of --longname
  Kbuild: Makefile.modbuiltin: include auto.conf and tristate.conf mandatory
  kbuild: remove auto.conf from prerequisite of phony targets
  kbuild: do not update config for 'make kernelrelease'
  kbuild: do not update config when running install targets
  kbuild: add .DELETE_ON_ERROR special target
  kbuild: use 'include' directive to load auto.conf from top Makefile
  kconfig: allow all config targets to write auto.conf if missing
  kconfig: make syncconfig update .config regardless of sym_change_count
  kconfig: create directories needed for syncconfig by itself
  kconfig: remove unneeded directory generation from local*config
  kconfig: split out useful helpers in confdata.c
  kconfig: rename file_write_dep and move it to confdata.c
  kconfig: fix typos in description of "choice" in kconfig-language.txt
  kconfig: handle format string before calling conf_message_callback()
  kconfig: rename SYMBOL_AUTO to SYMBOL_NO_WRITE
  kconfig: check for pkg-config on make {menu,n,g,x}config
2018-08-15 12:50:10 -07:00
Linus Torvalds e026bcc561 Kbuild updates for v4.19
- verify depmod is installed before modules_install
 
 - support build salt in case build ids must be unique between builds
 
 - allow users to specify additional host compiler flags via HOST*FLAGS,
   and rename internal variables to KBUILD_HOST*FLAGS
 
 - update buildtar script to drop vax support, add arm64 support
 
 - update builddeb script for better debarch support
 
 - document the pit-fall of if_changed usage
 
 - fix parallel build of UML with O= option
 
 - make 'samples' target depend on headers_install to fix build errors
 
 - remove deprecated host-progs variable
 
 - add a new coccinelle script for refcount_t vs atomic_t check
 
 - improve double-test coccinelle script
 
 - misc cleanups and fixes
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Merge tag 'kbuild-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - verify depmod is installed before modules_install

 - support build salt in case build ids must be unique between builds

 - allow users to specify additional host compiler flags via HOST*FLAGS,
   and rename internal variables to KBUILD_HOST*FLAGS

 - update buildtar script to drop vax support, add arm64 support

 - update builddeb script for better debarch support

 - document the pit-fall of if_changed usage

 - fix parallel build of UML with O= option

 - make 'samples' target depend on headers_install to fix build errors

 - remove deprecated host-progs variable

 - add a new coccinelle script for refcount_t vs atomic_t check

 - improve double-test coccinelle script

 - misc cleanups and fixes

* tag 'kbuild-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (41 commits)
  coccicheck: return proper error code on fail
  Coccinelle: doubletest: reduce side effect false positives
  kbuild: remove deprecated host-progs variable
  kbuild: make samples really depend on headers_install
  um: clean up archheaders recipe
  kbuild: add %asm-generic to no-dot-config-targets
  um: fix parallel building with O= option
  scripts: Add Python 3 support to tracing/draw_functrace.py
  builddeb: Add automatic support for sh{3,4}{,eb} architectures
  builddeb: Add automatic support for riscv* architectures
  builddeb: Add automatic support for m68k architecture
  builddeb: Add automatic support for or1k architecture
  builddeb: Add automatic support for sparc64 architecture
  builddeb: Add automatic support for mips{,64}r6{,el} architectures
  builddeb: Add automatic support for mips64el architecture
  builddeb: Add automatic support for ppc64 and powerpcspe architectures
  builddeb: Introduce functions to simplify kconfig tests in set_debarch
  builddeb: Drop check for 32-bit s390
  builddeb: Change architecture detection fallback to use dpkg-architecture
  builddeb: Skip architecture detection when KBUILD_DEBARCH is set
  ...
2018-08-15 12:09:03 -07:00
Linus Torvalds 85a0b791bc Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Heiko Carstens:
 "Since Martin is on vacation you get the s390 pull request from me:

   - Host large page support for KVM guests. As the patches have large
     impact on arch/s390/mm/ this series goes out via both the KVM and
     the s390 tree.

   - Add an option for no compression to the "Kernel compression mode"
     menu, this will come in handy with the rework of the early boot
     code.

   - A large rework of the early boot code that will make life easier
     for KASAN and KASLR. With the rework the bootable uncompressed
     image is not generated anymore, only the bzImage is available. For
     debuggung purposes the new "no compression" option is used.

   - Re-enable the gcc plugins as the issue with the latent entropy
     plugin is solved with the early boot code rework.

   - More spectre relates changes:
      + Detect the etoken facility and remove expolines automatically.
      + Add expolines to a few more indirect branches.

   - A rewrite of the common I/O layer trace points to make them
     consumable by 'perf stat'.

   - Add support for format-3 PCI function measurement blocks.

   - Changes for the zcrypt driver:
      + Add attributes to indicate the load of cards and queues.
      + Restructure some code for the upcoming AP device support in KVM.

   - Build flags improvements in various Makefiles.

   - A few fixes for the kdump support.

   - A couple of patches for gcc 8 compile warning cleanup.

   - Cleanup s390 specific proc handlers.

   - Add s390 support to the restartable sequence self tests.

   - Some PTR_RET vs PTR_ERR_OR_ZERO cleanup.

   - Lots of bug fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (107 commits)
  s390/dasd: fix hanging offline processing due to canceled worker
  s390/dasd: fix panic for failed online processing
  s390/mm: fix addressing exception after suspend/resume
  rseq/selftests: add s390 support
  s390: fix br_r1_trampoline for machines without exrl
  s390/lib: use expoline for all bcr instructions
  s390/numa: move initial setup of node_to_cpumask_map
  s390/kdump: Fix elfcorehdr size calculation
  s390/cpum_sf: save TOD clock base in SDBs for time conversion
  KVM: s390: Add huge page enablement control
  s390/mm: Add huge page gmap linking support
  s390/mm: hugetlb pages within a gmap can not be freed
  KVM: s390: Add skey emulation fault handling
  s390/mm: Add huge pmd storage key handling
  s390/mm: Clear skeys for newly mapped huge guest pmds
  s390/mm: Clear huge page storage keys on enable_skey
  s390/mm: Add huge page dirty sync support
  s390/mm: Add gmap pmd invalidation and clearing
  s390/mm: Add gmap pmd notification bit setting
  s390/mm: Add gmap pmd linking
  ...
2018-08-13 19:07:17 -07:00
Rob Landley 47f38ae08d init/Kconfig: Use short unix-style option instead of --longname
Avoids warning messages with the latest release of toybox, which never
bothered to implement the --longopts nothing was using.

Signed-off-by: Rob Landley <rob@landley.net>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-08-09 21:50:43 +09:00
Christoph Hellwig 87a4c37599 kconfig: include kernel/Kconfig.preempt from init/Kconfig
Almost all architectures include it.  Add a ARCH_NO_PREEMPT symbol to
disable preempt support for alpha, hexagon, non-coldfire m68k and
user mode Linux.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-08-02 08:06:54 +09:00
Christoph Hellwig 1572497cb0 kconfig: include common Kconfig files from top-level Kconfig
Instead of duplicating the source statements in every architecture just
do it once in the toplevel Kconfig file.

Note that with this the inclusion of arch/$(SRCARCH/Kconfig moves out of
the top-level Kconfig into arch/Kconfig so that don't violate ordering
constraits while keeping a sensible menu structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-08-02 08:03:23 +09:00
Christoph Hellwig 17c46a6aff kconfig: remove duplicate SWAP symbol defintions
microblaze and nios2 define their own always n SWAP symbols.  Remove those
and let the generic defintion do the right thing by adding a new symbol
to disable swap entirely.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-08-02 08:03:23 +09:00
Laura Abbott 9afb719e70 kbuild: Add build salt to the kernel and modules
In Fedora, the debug information is packaged separately (foo-debuginfo) and
can be installed separately. There's been a long standing issue where only
one version of a debuginfo info package can be installed at a time. There's
been an effort for Fedora for parallel debuginfo to rectify this problem.

Part of the requirement to allow parallel debuginfo to work is that build ids
are unique between builds. The existing upstream rpm implementation ensures
this by re-calculating the build-id using the version and release as a
seed. This doesn't work 100% for the kernel because of the vDSO which is
its own binary and doesn't get updated when embedded.

Fix this by adding some data in an ELF note for both the kernel and modules.
The data is controlled via a Kconfig option so distributions can set it
to an appropriate value to ensure uniqueness between builds.

Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-07-18 01:18:05 +09:00
Linus Torvalds 22d3e0c36e Kbuild fixes for v4.18
- introduce __diag_* macros and suppress -Wattribute-alias warnings from GCC 8
 
 - fix stack protector test script for x86_64
 
 - fix line number handling in Kconfig
 
 - document that '#' starts a comment in Kconfig
 
 - handle P_SYMBOL property in dump debugging of Kconfig
 
 - correct help message of LD_DEAD_CODE_DATA_ELIMINATION
 
 - fix occasional segmentation faults in Kconfig
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Merge tag 'kbuild-fixes-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - introduce __diag_* macros and suppress -Wattribute-alias warnings
   from GCC 8

 - fix stack protector test script for x86_64

 - fix line number handling in Kconfig

 - document that '#' starts a comment in Kconfig

 - handle P_SYMBOL property in dump debugging of Kconfig

 - correct help message of LD_DEAD_CODE_DATA_ELIMINATION

 - fix occasional segmentation faults in Kconfig

* tag 'kbuild-fixes-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kconfig: loop boundary condition fix
  kbuild: reword help of LD_DEAD_CODE_DATA_ELIMINATION
  kconfig: handle P_SYMBOL in print_symbol()
  kconfig: document Kconfig source file comments
  kconfig: fix line numbers for if-entries in menu tree
  stack-protector: Fix test with 32-bit userland and CONFIG_64BIT=y
  powerpc: Remove -Wattribute-alias pragmas
  disable -Wattribute-alias warning for SYSCALL_DEFINEx()
  kbuild: add macro for controlling warnings to linux/compiler.h
2018-06-30 13:05:30 -07:00
Masahiro Yamada 8b9d271240 kbuild: reword help of LD_DEAD_CODE_DATA_ELIMINATION
Since commit 5d20ee3192 ("kbuild: Allow LD_DEAD_CODE_DATA_ELIMINATION
to be selectable if enabled"), HAVE_LD_DEAD_CODE_DATA_ELIMINATION is
supposed to be selected by architectures that are capable of this
functionality.  LD_DEAD_CODE_DATA_ELIMINATION is now users' selection.
Update the help message.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-06-28 22:48:07 +09:00
Vasily Gorbik f16466af38 init/Kconfig: add an option for uncompressed kernel
Add "None" as the kernel compression mode.

This option is useful for debugging the kernel in slow simulation
environments, where decompressing and moving the kernel is awfully slow.

Uncompressed kernel implementation might allow early boot code to skip the
decompressor and jump right at uncompressed kernel image entry point.

Platforms implementing that should define HAVE_KERNEL_UNCOMPRESSED.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-06-25 10:14:40 +02:00
Christoph Hellwig cf65a0f6f6 dma-mapping: move all DMA mapping code to kernel/dma
Currently the code is split over various files with dma- prefixes in the
lib/ and drives/base directories, and the number of files keeps growing.
Move them into a single directory to keep the code together and remove
the file name prefixes.  To match the irq infrastructure this directory
is placed under the kernel/ directory.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-06-14 08:50:37 +02:00
Linus Torvalds be779f03d5 Kbuild updates for v4.18 (2nd)
- fix some bugs introduced by the recent Kconfig syntax extension
 
  - add some symbols about compiler information in Kconfig, such as
    CC_IS_GCC, CC_IS_CLANG, GCC_VERSION, etc.
 
  - test compiler capability for the stack protector in Kconfig, and
    clean-up Makefile
 
  - test compiler capability for GCC-plugins in Kconfig, and clean-up
    Makefile
 
  - allow to enable GCC-plugins for COMPILE_TEST
 
  - test compiler capability for KCOV in Kconfig and correct dependency
 
  - remove auto-detect mode of the GCOV format, which is now more nicely
    handled in Kconfig
 
  - test compiler capability for mprofile-kernel on PowerPC, and
    clean-up Makefile
 
  - misc cleanups
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Merge tag 'kbuild-v4.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull more Kbuild updates from Masahiro Yamada:

 - fix some bugs introduced by the recent Kconfig syntax extension

 - add some symbols about compiler information in Kconfig, such as
   CC_IS_GCC, CC_IS_CLANG, GCC_VERSION, etc.

 - test compiler capability for the stack protector in Kconfig, and
   clean-up Makefile

 - test compiler capability for GCC-plugins in Kconfig, and clean-up
   Makefile

 - allow to enable GCC-plugins for COMPILE_TEST

 - test compiler capability for KCOV in Kconfig and correct dependency

 - remove auto-detect mode of the GCOV format, which is now more nicely
   handled in Kconfig

 - test compiler capability for mprofile-kernel on PowerPC, and clean-up
   Makefile

 - misc cleanups

* tag 'kbuild-v4.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  linux/linkage.h: replace VMLINUX_SYMBOL_STR() with __stringify()
  kconfig: fix localmodconfig
  sh: remove no-op macro VMLINUX_SYMBOL()
  powerpc/kbuild: move -mprofile-kernel check to Kconfig
  Documentation: kconfig: add recommended way to describe compiler support
  gcc-plugins: disable GCC_PLUGIN_STRUCTLEAK_BYREF_ALL for COMPILE_TEST
  gcc-plugins: allow to enable GCC_PLUGINS for COMPILE_TEST
  gcc-plugins: test plugin support in Kconfig and clean up Makefile
  gcc-plugins: move GCC version check for PowerPC to Kconfig
  kcov: test compiler capability in Kconfig and correct dependency
  gcov: remove CONFIG_GCOV_FORMAT_AUTODETECT
  arm64: move GCC version check for ARCH_SUPPORTS_INT128 to Kconfig
  kconfig: add CC_IS_CLANG and CLANG_VERSION
  kconfig: add CC_IS_GCC and GCC_VERSION
  stack-protector: test compiler capability in Kconfig and drop AUTO mode
  kbuild: fix endless syncconfig in case arch Makefile sets CROSS_COMPILE
2018-06-13 08:40:34 -07:00
Linus Torvalds d82991a868 Merge branch 'core-rseq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull restartable sequence support from Thomas Gleixner:
 "The restartable sequences syscall (finally):

  After a lot of back and forth discussion and massive delays caused by
  the speculative distraction of maintainers, the core set of
  restartable sequences has finally reached a consensus.

  It comes with the basic non disputed core implementation along with
  support for arm, powerpc and x86 and a full set of selftests

  It was exposed to linux-next earlier this week, so it does not fully
  comply with the merge window requirements, but there is really no
  point to drag it out for yet another cycle"

* 'core-rseq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  rseq/selftests: Provide Makefile, scripts, gitignore
  rseq/selftests: Provide parametrized tests
  rseq/selftests: Provide basic percpu ops test
  rseq/selftests: Provide basic test
  rseq/selftests: Provide rseq library
  selftests/lib.mk: Introduce OVERRIDE_TARGETS
  powerpc: Wire up restartable sequences system call
  powerpc: Add syscall detection for restartable sequences
  powerpc: Add support for restartable sequences
  x86: Wire up restartable sequence system call
  x86: Add support for restartable sequences
  arm: Wire up restartable sequences system call
  arm: Add syscall detection for restartable sequences
  arm: Add restartable sequences support
  rseq: Introduce restartable sequences system call
  uapi/headers: Provide types_32_64.h
2018-06-10 10:17:09 -07:00
Masahiro Yamada 469cb7376c kconfig: add CC_IS_CLANG and CLANG_VERSION
This will be useful to describe the clang version dependency.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2018-06-08 18:56:01 +09:00
Masahiro Yamada a435389898 kconfig: add CC_IS_GCC and GCC_VERSION
This will be useful to specify the required compiler version,
like this:

config FOO
        bool "Use Foo"
        depends on GCC_VERSION >= 40800
        help
          This feature requires GCC 4.8 or newer.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2018-06-08 18:56:01 +09:00
Linus Torvalds 1c8c5a9d38 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) Add Maglev hashing scheduler to IPVS, from Inju Song.

 2) Lots of new TC subsystem tests from Roman Mashak.

 3) Add TCP zero copy receive and fix delayed acks and autotuning with
    SO_RCVLOWAT, from Eric Dumazet.

 4) Add XDP_REDIRECT support to mlx5 driver, from Jesper Dangaard
    Brouer.

 5) Add ttl inherit support to vxlan, from Hangbin Liu.

 6) Properly separate ipv6 routes into their logically independant
    components. fib6_info for the routing table, and fib6_nh for sets of
    nexthops, which thus can be shared. From David Ahern.

 7) Add bpf_xdp_adjust_tail helper, which can be used to generate ICMP
    messages from XDP programs. From Nikita V. Shirokov.

 8) Lots of long overdue cleanups to the r8169 driver, from Heiner
    Kallweit.

 9) Add BTF ("BPF Type Format"), from Martin KaFai Lau.

10) Add traffic condition monitoring to iwlwifi, from Luca Coelho.

11) Plumb extack down into fib_rules, from Roopa Prabhu.

12) Add Flower classifier offload support to igb, from Vinicius Costa
    Gomes.

13) Add UDP GSO support, from Willem de Bruijn.

14) Add documentation for eBPF helpers, from Quentin Monnet.

15) Add TLS tx offload to mlx5, from Ilya Lesokhin.

16) Allow applications to be given the number of bytes available to read
    on a socket via a control message returned from recvmsg(), from
    Soheil Hassas Yeganeh.

17) Add x86_32 eBPF JIT compiler, from Wang YanQing.

18) Add AF_XDP sockets, with zerocopy support infrastructure as well.
    From Björn Töpel.

19) Remove indirect load support from all of the BPF JITs and handle
    these operations in the verifier by translating them into native BPF
    instead. From Daniel Borkmann.

20) Add GRO support to ipv6 gre tunnels, from Eran Ben Elisha.

21) Allow XDP programs to do lookups in the main kernel routing tables
    for forwarding. From David Ahern.

22) Allow drivers to store hardware state into an ELF section of kernel
    dump vmcore files, and use it in cxgb4. From Rahul Lakkireddy.

23) Various RACK and loss detection improvements in TCP, from Yuchung
    Cheng.

24) Add TCP SACK compression, from Eric Dumazet.

25) Add User Mode Helper support and basic bpfilter infrastructure, from
    Alexei Starovoitov.

26) Support ports and protocol values in RTM_GETROUTE, from Roopa
    Prabhu.

27) Support bulking in ->ndo_xdp_xmit() API, from Jesper Dangaard
    Brouer.

28) Add lots of forwarding selftests, from Petr Machata.

29) Add generic network device failover driver, from Sridhar Samudrala.

* ra.kernel.org:/pub/scm/linux/kernel/git/davem/net-next: (1959 commits)
  strparser: Add __strp_unpause and use it in ktls.
  rxrpc: Fix terminal retransmission connection ID to include the channel
  net: hns3: Optimize PF CMDQ interrupt switching process
  net: hns3: Fix for VF mailbox receiving unknown message
  net: hns3: Fix for VF mailbox cannot receiving PF response
  bnx2x: use the right constant
  Revert "net: sched: cls: Fix offloading when ingress dev is vxlan"
  net: dsa: b53: Fix for brcm tag issue in Cygnus SoC
  enic: fix UDP rss bits
  netdev-FAQ: clarify DaveM's position for stable backports
  rtnetlink: validate attributes in do_setlink()
  mlxsw: Add extack messages for port_{un, }split failures
  netdevsim: Add extack error message for devlink reload
  devlink: Add extack to reload and port_{un, }split operations
  net: metrics: add proper netlink validation
  ipmr: fix error path when ipmr_new_table fails
  ip6mr: only set ip6mr_table from setsockopt when ip6mr_new_table succeeds
  net: hns3: remove unused hclgevf_cfg_func_mta_filter
  netfilter: provide udp*_lib_lookup for nf_tproxy
  qed*: Utilize FW 8.37.2.0
  ...
2018-06-06 18:39:49 -07:00
Linus Torvalds 0ad39cb3d7 Kconfig updates for v4.18
Kconfig now supports new functionality to perform textual substitution.
 It has been a while since Linus suggested to move compiler option tests
 from makefiles to Kconfig. Finally, here it is. The implementation has
 been generalized into a Make-like macro language. Some built-in functions
 such as 'shell' are provided. Variables and user-defined functions are
 also supported so that 'cc-option', 'ld-option', etc. are implemented as
 macros.
 
 Summary:
 
 - refactor package checks for building {m,n,q,g}conf
 
 - remove unused/unmaintained localization support
 
 - remove Kbuild cache
 
 - drop CONFIG_CROSS_COMPILE support
 
 - replace 'option env=' with direct variable expansion
 
 - add built-in functions such as 'shell'
 
 - support variables and user-defined functions
 
 - add helper macros as as 'cc-option'
 
 - add unit tests and a document of the new macro language
 
 - add 'testconfig' to help
 
 - fix warnings from GCC 8.1
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Merge tag 'kconfig-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kconfig updates from Masahiro Yamada:
 "Kconfig now supports new functionality to perform textual
  substitution. It has been a while since Linus suggested to move
  compiler option tests from makefiles to Kconfig. Finally, here it is.

  The implementation has been generalized into a Make-like macro
  language.

  Some built-in functions such as 'shell' are provided. Variables and
  user-defined functions are also supported so that 'cc-option',
  'ld-option', etc. are implemented as macros.

  Summary:

   - refactor package checks for building {m,n,q,g}conf

   - remove unused/unmaintained localization support

   - remove Kbuild cache

   - drop CONFIG_CROSS_COMPILE support

   - replace 'option env=' with direct variable expansion

   - add built-in functions such as 'shell'

   - support variables and user-defined functions

   - add helper macros as as 'cc-option'

   - add unit tests and a document of the new macro language

   - add 'testconfig' to help

   - fix warnings from GCC 8.1"

* tag 'kconfig-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (30 commits)
  kconfig: Avoid format overflow warning from GCC 8.1
  kbuild: Move last word of nconfig help to the previous line
  kconfig: Add testconfig into make help output
  kconfig: add basic helper macros to scripts/Kconfig.include
  kconfig: show compiler version text in the top comment
  kconfig: test: add Kconfig macro language tests
  Documentation: kconfig: document a new Kconfig macro language
  kconfig: error out if a recursive variable references itself
  kconfig: add 'filename' and 'lineno' built-in variables
  kconfig: add 'info', 'warning-if', and 'error-if' built-in functions
  kconfig: expand lefthand side of assignment statement
  kconfig: support append assignment operator
  kconfig: support simply expanded variable
  kconfig: support user-defined function and recursively expanded variable
  kconfig: begin PARAM state only when seeing a command keyword
  kconfig: replace $(UNAME_RELEASE) with function call
  kconfig: add 'shell' built-in function
  kconfig: add built-in function support
  kconfig: make default prompt of mainmenu less specific
  kconfig: remove sym_expand_string_value()
  ...
2018-06-06 11:31:45 -07:00
Linus Torvalds 8715ee75fe Kbuild updates for v4.18
- improve fixdep to coalesce consecutive slashes in dep-files
 
 - fix some issues of the maintainer string generation in deb-pkg script
 
 - remove unused CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX and clean-up
   several tools and linker scripts
 
 - clean-up modpost
 
 - allow to enable the dead code/data elimination for PowerPC in EXPERT mode
 
 - improve two coccinelle scripts for better performance
 
 - pass endianness and machine size flags to sparse for all architecture
 
 - misc fixes
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Merge tag 'kbuild-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - improve fixdep to coalesce consecutive slashes in dep-files

 - fix some issues of the maintainer string generation in deb-pkg script

 - remove unused CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX and clean-up
   several tools and linker scripts

 - clean-up modpost

 - allow to enable the dead code/data elimination for PowerPC in EXPERT
   mode

 - improve two coccinelle scripts for better performance

 - pass endianness and machine size flags to sparse for all architecture

 - misc fixes

* tag 'kbuild-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (25 commits)
  kbuild: add machine size to CHECKFLAGS
  kbuild: add endianness flag to CHEKCFLAGS
  kbuild: $(CHECK) doesnt need NOSTDINC_FLAGS twice
  scripts: Fixed printf format mismatch
  scripts/tags.sh: use `find` for $ALLSOURCE_ARCHS generation
  coccinelle: deref_null: improve performance
  coccinelle: mini_lock: improve performance
  powerpc: Allow LD_DEAD_CODE_DATA_ELIMINATION to be selected
  kbuild: Allow LD_DEAD_CODE_DATA_ELIMINATION to be selectable if enabled
  kbuild: LD_DEAD_CODE_DATA_ELIMINATION no -ffunction-sections/-fdata-sections for module build
  kbuild: Fix asm-generic/vmlinux.lds.h for LD_DEAD_CODE_DATA_ELIMINATION
  modpost: constify *modname function argument where possible
  modpost: remove redundant is_vmlinux() test
  modpost: use strstarts() helper more widely
  modpost: pass struct elf_info pointer to get_modinfo()
  checkpatch: remove VMLINUX_SYMBOL() check
  vmlinux.lds.h: remove no-op macro VMLINUX_SYMBOL()
  kbuild: remove CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX
  export.h: remove code for prefixing symbols with underscore
  depmod.sh: remove symbol prefix support
  ...
2018-06-06 11:00:15 -07:00
Mathieu Desnoyers d7822b1e24 rseq: Introduce restartable sequences system call
Expose a new system call allowing each thread to register one userspace
memory area to be used as an ABI between kernel and user-space for two
purposes: user-space restartable sequences and quick access to read the
current CPU number value from user-space.

* Restartable sequences (per-cpu atomics)

Restartables sequences allow user-space to perform update operations on
per-cpu data without requiring heavy-weight atomic operations.

The restartable critical sections (percpu atomics) work has been started
by Paul Turner and Andrew Hunter. It lets the kernel handle restart of
critical sections. [1] [2] The re-implementation proposed here brings a
few simplifications to the ABI which facilitates porting to other
architectures and speeds up the user-space fast path.

Here are benchmarks of various rseq use-cases.

Test hardware:

arm32: ARMv7 Processor rev 4 (v7l) "Cubietruck", 2-core
x86-64: Intel E5-2630 v3@2.40GHz, 16-core, hyperthreading

The following benchmarks were all performed on a single thread.

* Per-CPU statistic counter increment

                getcpu+atomic (ns/op)    rseq (ns/op)    speedup
arm32:                344.0                 31.4          11.0
x86-64:                15.3                  2.0           7.7

* LTTng-UST: write event 32-bit header, 32-bit payload into tracer
             per-cpu buffer

                getcpu+atomic (ns/op)    rseq (ns/op)    speedup
arm32:               2502.0                 2250.0         1.1
x86-64:               117.4                   98.0         1.2

* liburcu percpu: lock-unlock pair, dereference, read/compare word

                getcpu+atomic (ns/op)    rseq (ns/op)    speedup
arm32:                751.0                 128.5          5.8
x86-64:                53.4                  28.6          1.9

* jemalloc memory allocator adapted to use rseq

Using rseq with per-cpu memory pools in jemalloc at Facebook (based on
rseq 2016 implementation):

The production workload response-time has 1-2% gain avg. latency, and
the P99 overall latency drops by 2-3%.

* Reading the current CPU number

Speeding up reading the current CPU number on which the caller thread is
running is done by keeping the current CPU number up do date within the
cpu_id field of the memory area registered by the thread. This is done
by making scheduler preemption set the TIF_NOTIFY_RESUME flag on the
current thread. Upon return to user-space, a notify-resume handler
updates the current CPU value within the registered user-space memory
area. User-space can then read the current CPU number directly from
memory.

Keeping the current cpu id in a memory area shared between kernel and
user-space is an improvement over current mechanisms available to read
the current CPU number, which has the following benefits over
alternative approaches:

- 35x speedup on ARM vs system call through glibc
- 20x speedup on x86 compared to calling glibc, which calls vdso
  executing a "lsl" instruction,
- 14x speedup on x86 compared to inlined "lsl" instruction,
- Unlike vdso approaches, this cpu_id value can be read from an inline
  assembly, which makes it a useful building block for restartable
  sequences.
- The approach of reading the cpu id through memory mapping shared
  between kernel and user-space is portable (e.g. ARM), which is not the
  case for the lsl-based x86 vdso.

On x86, yet another possible approach would be to use the gs segment
selector to point to user-space per-cpu data. This approach performs
similarly to the cpu id cache, but it has two disadvantages: it is
not portable, and it is incompatible with existing applications already
using the gs segment selector for other purposes.

Benchmarking various approaches for reading the current CPU number:

ARMv7 Processor rev 4 (v7l)
Machine model: Cubietruck
- Baseline (empty loop):                                    8.4 ns
- Read CPU from rseq cpu_id:                               16.7 ns
- Read CPU from rseq cpu_id (lazy register):               19.8 ns
- glibc 2.19-0ubuntu6.6 getcpu:                           301.8 ns
- getcpu system call:                                     234.9 ns

x86-64 Intel(R) Xeon(R) CPU E5-2630 v3 @ 2.40GHz:
- Baseline (empty loop):                                    0.8 ns
- Read CPU from rseq cpu_id:                                0.8 ns
- Read CPU from rseq cpu_id (lazy register):                0.8 ns
- Read using gs segment selector:                           0.8 ns
- "lsl" inline assembly:                                   13.0 ns
- glibc 2.19-0ubuntu6 getcpu:                              16.6 ns
- getcpu system call:                                      53.9 ns

- Speed (benchmark taken on v8 of patchset)

Running 10 runs of hackbench -l 100000 seems to indicate, contrary to
expectations, that enabling CONFIG_RSEQ slightly accelerates the
scheduler:

Configuration: 2 sockets * 8-core Intel(R) Xeon(R) CPU E5-2630 v3 @
2.40GHz (directly on hardware, hyperthreading disabled in BIOS, energy
saving disabled in BIOS, turboboost disabled in BIOS, cpuidle.off=1
kernel parameter), with a Linux v4.6 defconfig+localyesconfig,
restartable sequences series applied.

* CONFIG_RSEQ=n

avg.:      41.37 s
std.dev.:   0.36 s

* CONFIG_RSEQ=y

avg.:      40.46 s
std.dev.:   0.33 s

- Size

On x86-64, between CONFIG_RSEQ=n/y, the text size increase of vmlinux is
567 bytes, and the data size increase of vmlinux is 5696 bytes.

[1] https://lwn.net/Articles/650333/
[2] http://www.linuxplumbersconf.org/2013/ocw/system/presentations/1695/original/LPC%20-%20PerCpu%20Atomics.pdf

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Watson <davejwatson@fb.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Chris Lameter <cl@linux.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Andrew Hunter <ahh@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Paul Turner <pjt@google.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ben Maurer <bmaurer@fb.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: linux-api@vger.kernel.org
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20151027235635.16059.11630.stgit@pjt-glaptop.roam.corp.google.com
Link: http://lkml.kernel.org/r/20150624222609.6116.86035.stgit@kitami.mtv.corp.google.com
Link: https://lkml.kernel.org/r/20180602124408.8430-3-mathieu.desnoyers@efficios.com
2018-06-06 11:58:31 +02:00
Masahiro Yamada 2972666ac9 kconfig: replace $(UNAME_RELEASE) with function call
Now that 'shell' function is supported, this can be self-contained in
Kconfig.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-05-29 03:31:19 +09:00
Masahiro Yamada 104daea149 kconfig: reference environment variables directly and remove 'option env='
To get access to environment variables, Kconfig needs to define a
symbol using "option env=" syntax.  It is tedious to add a symbol entry
for each environment variable given that we need to define much more
such as 'CC', 'AS', 'srctree' etc. to evaluate the compiler capability
in Kconfig.

Adding '$' for symbol references is grammatically inconsistent.
Looking at the code, the symbols prefixed with 'S' are expanded by:
 - conf_expand_value()
   This is used to expand 'arch/$ARCH/defconfig' and 'defconfig_list'
 - sym_expand_string_value()
   This is used to expand strings in 'source' and 'mainmenu'

All of them are fixed values independent of user configuration.  So,
they can be changed into the direct expansion instead of symbols.

This change makes the code much cleaner.  The bounce symbols 'SRCARCH',
'ARCH', 'SUBARCH', 'KERNELVERSION' are gone.

sym_init() hard-coding 'UNAME_RELEASE' is also gone.  'UNAME_RELEASE'
should be replaced with an environment variable.

ARCH_DEFCONFIG is a normal symbol, so it should be simply referenced
without '$' prefix.

The new syntax is addicted by Make.  The variable reference needs
parentheses, like $(FOO), but you can omit them for single-letter
variables, like $F.  Yet, in Makefiles, people tend to use the
parenthetical form for consistency / clarification.

At this moment, only the environment variable is supported, but I will
extend the concept of 'variable' later on.

The variables are expanded in the lexer so we can simplify the token
handling on the parser side.

For example, the following code works.

[Example code]

  config MY_TOOLCHAIN_LIST
          string
          default "My tools: CC=$(CC), AS=$(AS), CPP=$(CPP)"

[Result]

  $ make -s alldefconfig && tail -n 1 .config
  CONFIG_MY_TOOLCHAIN_LIST="My tools: CC=gcc, AS=as, CPP=gcc -E"

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2018-05-29 03:28:58 +09:00
Masahiro Yamada f1089c92da kbuild: remove CONFIG_CROSS_COMPILE support
Kbuild provides a couple of ways to specify CROSS_COMPILE:

[1] Command line
[2] Environment
[3] arch/*/Makefile (only some architectures)
[4] CONFIG_CROSS_COMPILE

[4] is problematic for the compiler capability tests in Kconfig.
CONFIG_CROSS_COMPILE allows users to change the compiler prefix from
'make menuconfig', etc.  It means, the compiler options would have
to be all re-calculated everytime CONFIG_CROSS_COMPILE is changed.

To avoid complexity and performance issues, I'd like to evaluate
the shell commands statically, i.e. only parsing Kconfig files.

I guess the majority is [1] or [2].  Currently, there are only
5 defconfig files that specify CONFIG_CROSS_COMPILE.
  arch/arm/configs/lpc18xx_defconfig
  arch/hexagon/configs/comet_defconfig
  arch/nds32/configs/defconfig
  arch/openrisc/configs/or1ksim_defconfig
  arch/openrisc/configs/simple_smp_defconfig

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2018-05-29 03:28:58 +09:00
David S. Miller 6f6e434aa2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
S390 bpf_jit.S is removed in net-next and had changes in 'net',
since that code isn't used any more take the removal.

TLS data structures split the TX and RX components in 'net-next',
put the new struct members from the bug fix in 'net' into the RX
part.

The 'net-next' tree had some reworking of how the ERSPAN code works in
the GRE tunneling code, overlapping with a one-line headroom
calculation fix in 'net'.

Overlapping changes in __sock_map_ctx_update_elem(), keep the bits
that read the prog members via READ_ONCE() into local variables
before using them.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-21 16:01:54 -04:00
Sebastian Andrzej Siewior cd33d8803b sched/fair: Fix documentation file path
The 'tip' prefix probably referred to the -tip tree and is not required,
remove it.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180515165328.24899-1-bigeasy@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-18 09:05:28 +02:00
Nicholas Piggin 5d20ee3192 kbuild: Allow LD_DEAD_CODE_DATA_ELIMINATION to be selectable if enabled
Architectures that are capable can select
HAVE_LD_DEAD_CODE_DATA_ELIMINATION to enable selection of that
option (as an EXPERT kernel option).

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-05-17 22:45:01 +09:00
Song Liu bae77c5eb5 bpf: enable stackmap with build_id in nmi context
Currently, we cannot parse build_id in nmi context because of
up_read(&current->mm->mmap_sem), this makes stackmap with build_id
less useful. This patch enables parsing build_id in nmi by putting
the up_read() call in irq_work. To avoid memory allocation in nmi
context, we use per cpu variable for the irq_work. As a result, only
one irq_work per cpu is allowed. If the irq_work is in-use, we
fallback to only report ips.

Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-14 23:29:45 +02:00
Linus Torvalds 9fb71c2f23 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
 "A set of fixes and updates for x86:

   - Address a swiotlb regression which was caused by the recent DMA
     rework and made driver fail because dma_direct_supported() returned
     false

   - Fix a signedness bug in the APIC ID validation which caused invalid
     APIC IDs to be detected as valid thereby bloating the CPU possible
     space.

   - Fix inconsisten config dependcy/select magic for the MFD_CS5535
     driver.

   - Fix a corruption of the physical address space bits when encryption
     has reduced the address space and late cpuinfo updates overwrite
     the reduced bit information with the original value.

   - Dominiks syscall rework which consolidates the architecture
     specific syscall functions so all syscalls can be wrapped with the
     same macros. This allows to switch x86/64 to struct pt_regs based
     syscalls. Extend the clearing of user space controlled registers in
     the entry patch to the lower registers"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/apic: Fix signedness bug in APIC ID validity checks
  x86/cpu: Prevent cpuinfo_x86::x86_phys_bits adjustment corruption
  x86/olpc: Fix inconsistent MFD_CS5535 configuration
  swiotlb: Use dma_direct_supported() for swiotlb_ops
  syscalls/x86: Adapt syscall_wrapper.h to the new syscall stub naming convention
  syscalls/core, syscalls/x86: Rename struct pt_regs-based sys_*() to __x64_sys_*()
  syscalls/core, syscalls/x86: Clean up compat syscall stub naming convention
  syscalls/core, syscalls/x86: Clean up syscall stub naming convention
  syscalls/x86: Extend register clearing on syscall entry to lower registers
  syscalls/x86: Unconditionally enable 'struct pt_regs' based syscalls on x86_64
  syscalls/x86: Use 'struct pt_regs' based syscall calling for IA32_EMULATION and x32
  syscalls/core: Prepare CONFIG_ARCH_HAS_SYSCALL_WRAPPER=y for compat syscalls
  syscalls/x86: Use 'struct pt_regs' based syscall calling convention for 64-bit syscalls
  syscalls/core: Introduce CONFIG_ARCH_HAS_SYSCALL_WRAPPER=y
  x86/syscalls: Don't pointlessly reload the system call number
  x86/mm: Fix documentation of module mapping range with 4-level paging
  x86/cpuid: Switch to 'static const' specifier
2018-04-15 16:12:35 -07:00
Linus Torvalds 1b2951dd99 This is the bulk of GPIO changes for the v4.17 kernel cycle:
New drivers:
 
 - Nintendo Wii GameCube GPIO, known as "Hollywood"
 
 - Raspberry Pi mailbox service GPIO expander
 
 - Spreadtrum main SC9860 SoC and IEC GPIO controllers.
 
 Improvements:
 
 - Implemented .get_multiple() callback for most of the
   high-performance industrial GPIO cards for the ISA bus.
 
 - ISA GPIO drivers now select the ISA_BUS_API instead of
   depending on it. This is merged with the same pattern
   for all the ISA drivers and some other Kconfig cleanups
   related to this.
 
 Cleanup:
 
 - Delete the TZ1090 GPIO drivers following the deletion of
   this SoC from the ARM tree.
 
 - Move the documentation over to driver-api to conform with
   the rest of the kernel documentation build.
 
 - Continue to make the GPIO drivers include only
   <linux/gpio/driver.h> and not the too broad <linux/gpio.h>
   that we want to get rid of.
 
 - Managed to remove VLA allocation from two drivers pending
   more fixes in this area for the next merge window.
 
 - Misc janitorial fixes.
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Merge tag 'gpio-v4.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Linus Walleij:
 "This is the bulk of GPIO changes for the v4.17 kernel cycle:

  New drivers:

   - Nintendo Wii GameCube GPIO, known as "Hollywood"

   - Raspberry Pi mailbox service GPIO expander

   - Spreadtrum main SC9860 SoC and IEC GPIO controllers.

  Improvements:

   - Implemented .get_multiple() callback for most of the
     high-performance industrial GPIO cards for the ISA bus.

   - ISA GPIO drivers now select the ISA_BUS_API instead of depending on
     it. This is merged with the same pattern for all the ISA drivers
     and some other Kconfig cleanups related to this.

  Cleanup:

   - Delete the TZ1090 GPIO drivers following the deletion of this SoC
     from the ARM tree.

   - Move the documentation over to driver-api to conform with the rest
     of the kernel documentation build.

   - Continue to make the GPIO drivers include only
     <linux/gpio/driver.h> and not the too broad <linux/gpio.h> that we
     want to get rid of.

   - Managed to remove VLA allocation from two drivers pending more
     fixes in this area for the next merge window.

   - Misc janitorial fixes"

* tag 'gpio-v4.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (77 commits)
  gpio: Add Spreadtrum PMIC EIC driver support
  gpio: Add Spreadtrum EIC driver support
  dt-bindings: gpio: Add Spreadtrum EIC controller documentation
  gpio: ath79: Fix potential NULL dereference in ath79_gpio_probe()
  pinctrl: qcom: Don't allow protected pins to be requested
  gpiolib: Support 'gpio-reserved-ranges' property
  gpiolib: Change bitmap allocation to kmalloc_array
  gpiolib: Extract mask allocation into subroutine
  dt-bindings: gpio: Add a gpio-reserved-ranges property
  gpio: mockup: fix a potential crash when creating debugfs entries
  gpio: pca953x: add compatibility for pcal6524 and pcal9555a
  gpio: dwapb: Add support for a bus clock
  gpio: Remove VLA from xra1403 driver
  gpio: Remove VLA from MAX3191X driver
  gpio: ws16c48: Implement get_multiple callback
  gpio: gpio-mm: Implement get_multiple callback
  gpio: 104-idi-48: Implement get_multiple callback
  gpio: 104-dio-48e: Implement get_multiple callback
  gpio: pcie-idio-24: Implement get_multiple/set_multiple callbacks
  gpio: pci-idio-16: Implement get_multiple callback
  ...
2018-04-05 09:51:41 -07:00
Dominik Brodowski 7303e30ec1 syscalls/core: Prepare CONFIG_ARCH_HAS_SYSCALL_WRAPPER=y for compat syscalls
It may be useful for an architecture to override the definitions of the
COMPAT_SYSCALL_DEFINE0() and __COMPAT_SYSCALL_DEFINEx() macros in
<linux/compat.h>, in particular to use a different calling convention
for syscalls. This patch provides a mechanism to do so, based on the
previously introduced CONFIG_ARCH_HAS_SYSCALL_WRAPPER. If it is enabled,
<asm/sycall_wrapper.h> is included in <linux/compat.h> and may be used
to define the macros mentioned above. Moreover, as the syscall calling
convention may be different if CONFIG_ARCH_HAS_SYSCALL_WRAPPER is set,
the compat syscall function prototypes in <linux/compat.h> are #ifndef'd
out in that case.

As some of the syscalls and/or compat syscalls may not be present,
the COND_SYSCALL() and COND_SYSCALL_COMPAT() macros in kernel/sys_ni.c
as well as the SYS_NI() and COMPAT_SYS_NI() macros in
kernel/time/posix-stubs.c can be re-defined in <asm/syscall_wrapper.h> iff
CONFIG_ARCH_HAS_SYSCALL_WRAPPER is enabled.

Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180405095307.3730-5-linux@dominikbrodowski.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-05 16:59:38 +02:00
Dominik Brodowski 1bd21c6c21 syscalls/core: Introduce CONFIG_ARCH_HAS_SYSCALL_WRAPPER=y
It may be useful for an architecture to override the definitions of the
SYSCALL_DEFINE0() and __SYSCALL_DEFINEx() macros in <linux/syscalls.h>,
in particular to use a different calling convention for syscalls.

This patch provides a mechanism to do so: It introduces
CONFIG_ARCH_HAS_SYSCALL_WRAPPER. If it is enabled, <asm/sycall_wrapper.h>
is included in <linux/syscalls.h> and may be used to define the macros
mentioned above. Moreover, as the syscall calling convention may be
different if CONFIG_ARCH_HAS_SYSCALL_WRAPPER is set, the syscall function
prototypes in <linux/syscalls.h> are #ifndef'd out in that case.

Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180405095307.3730-3-linux@dominikbrodowski.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-05 16:59:25 +02:00
Arnd Bergmann a687a53370 treewide: simplify Kconfig dependencies for removed archs
A lot of Kconfig symbols have architecture specific dependencies.
In those cases that depend on architectures we have already removed,
they can be omitted.

Acked-by: Kalle Valo <kvalo@codeaurora.org>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-03-26 15:55:57 +02:00
David Howells 739d875dd6 mn10300: Remove the architecture
Remove the MN10300 arch as the hardware is defunct.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Masahiro Yamada <yamada.masahiro@socionext.com>
cc: linux-am33-list@redhat.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-03-09 23:19:56 +01:00