Commit Graph

1782 Commits

Author SHA1 Message Date
Linus Torvalds
42f52e1c59 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
 "The main changes are:

   - Migrate CPU-intense 'misfit' tasks on asymmetric capacity systems,
     to better utilize (much) faster 'big core' CPUs. (Morten Rasmussen,
     Valentin Schneider)

   - Topology handling improvements, in particular when CPU capacity
     changes and related load-balancing fixes/improvements (Morten
     Rasmussen)

   - ... plus misc other improvements, fixes and updates"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (28 commits)
  sched/completions/Documentation: Add recommendation for dynamic and ONSTACK completions
  sched/completions/Documentation: Clean up the document some more
  sched/completions/Documentation: Fix a couple of punctuation nits
  cpu/SMT: State SMT is disabled even with nosmt and without "=force"
  sched/core: Fix comment regarding nr_iowait_cpu() and get_iowait_load()
  sched/fair: Remove setting task's se->runnable_weight during PELT update
  sched/fair: Disable LB_BIAS by default
  sched/pelt: Fix warning and clean up IRQ PELT config
  sched/topology: Make local variables static
  sched/debug: Use symbolic names for task state constants
  sched/numa: Remove unused numa_stats::nr_running field
  sched/numa: Remove unused code from update_numa_stats()
  sched/debug: Explicitly cast sched_feat() to bool
  sched/core: Disable SD_PREFER_SIBLING on asymmetric CPU capacity domains
  sched/fair: Don't move tasks to lower capacity CPUs unless necessary
  sched/fair: Set rq->rd->overload when misfit
  sched/fair: Wrap rq->rd->overload accesses with READ/WRITE_ONCE()
  sched/core: Change root_domain->overload type to int
  sched/fair: Change 'prefer_sibling' type to bool
  sched/fair: Kick nohz balance if rq->misfit_task_load
  ...
2018-10-23 15:00:03 +01:00
Linus Torvalds
0200fbdd43 Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking and misc x86 updates from Ingo Molnar:
 "Lots of changes in this cycle - in part because locking/core attracted
  a number of related x86 low level work which was easier to handle in a
  single tree:

   - Linux Kernel Memory Consistency Model updates (Alan Stern, Paul E.
     McKenney, Andrea Parri)

   - lockdep scalability improvements and micro-optimizations (Waiman
     Long)

   - rwsem improvements (Waiman Long)

   - spinlock micro-optimization (Matthew Wilcox)

   - qspinlocks: Provide a liveness guarantee (more fairness) on x86.
     (Peter Zijlstra)

   - Add support for relative references in jump tables on arm64, x86
     and s390 to optimize jump labels (Ard Biesheuvel, Heiko Carstens)

   - Be a lot less permissive on weird (kernel address) uaccess faults
     on x86: BUG() when uaccess helpers fault on kernel addresses (Jann
     Horn)

   - macrofy x86 asm statements to un-confuse the GCC inliner. (Nadav
     Amit)

   - ... and a handful of other smaller changes as well"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (57 commits)
  locking/lockdep: Make global debug_locks* variables read-mostly
  locking/lockdep: Fix debug_locks off performance problem
  locking/pvqspinlock: Extend node size when pvqspinlock is configured
  locking/qspinlock_stat: Count instances of nested lock slowpaths
  locking/qspinlock, x86: Provide liveness guarantee
  x86/asm: 'Simplify' GEN_*_RMWcc() macros
  locking/qspinlock: Rework some comments
  locking/qspinlock: Re-order code
  locking/lockdep: Remove duplicated 'lock_class_ops' percpu array
  x86/defconfig: Enable CONFIG_USB_XHCI_HCD=y
  futex: Replace spin_is_locked() with lockdep
  locking/lockdep: Make class->ops a percpu counter and move it under CONFIG_DEBUG_LOCKDEP=y
  x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs
  x86/cpufeature: Macrofy inline assembly code to work around GCC inlining bugs
  x86/extable: Macrofy inline assembly code to work around GCC inlining bugs
  x86/paravirt: Work around GCC inlining bugs when compiling paravirt ops
  x86/bug: Macrofy the BUG table section handling, to work around GCC inlining bugs
  x86/alternatives: Macrofy lock prefixes to work around GCC inlining bugs
  x86/refcount: Work around GCC inlining bug
  x86/objtool: Use asm macros to work around GCC inlining bugs
  ...
2018-10-23 13:08:53 +01:00
Martin Schwidefsky
53c99bd665 init: add arch_call_rest_init to allow stack switching
With CONFIG_VMAP_STACK=y the kernel stack of all tasks should be
allocated in the vmalloc space. The initial stack used for all
the early init code is in the init_thread_union. To be able to
switch from this early stack to a properly allocated stack
from vmalloc the architecture needs a switch-over point.

Introduce the arch_call_rest_init() function with a weak definition
in init/main.c with the only purpose to call rest_init() from the
end of start_kernel(). The architecture override can then do the
necessary magic to switch to the new vmalloc'ed stack.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-10-09 11:20:55 +02:00
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
Ard Biesheuvel
1948367768 jump_label: Annotate entries that operate on __init code earlier
Jump table entries are mostly read-only, with the exception of the
init and module loader code that defuses entries that point into init
code when the code being referred to is freed.

For robustness, it would be better to move these entries into the
ro_after_init section, but clearing the 'code' member of each jump
table entry referring to init code at module load time races with the
module_enable_ro() call that remaps the ro_after_init section read
only, so we'd like to do it earlier.

So given that whether such an entry refers to init code can be decided
much earlier, we can pull this check forward. Since we may still need
the code entry at this point, let's switch to setting a low bit in the
'key' member just like we do to annotate the default state of a jump
table entry.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Jessica Yu <jeyu@kernel.org>
Link: https://lkml.kernel.org/r/20180919065144.25010-8-ard.biesheuvel@linaro.org
2018-09-27 17:56:48 +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
Linus Torvalds
cd9b44f907 Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:

 - the rest of MM

 - procfs updates

 - various misc things

 - more y2038 fixes

 - get_maintainer updates

 - lib/ updates

 - checkpatch updates

 - various epoll updates

 - autofs updates

 - hfsplus

 - some reiserfs work

 - fatfs updates

 - signal.c cleanups

 - ipc/ updates

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (166 commits)
  ipc/util.c: update return value of ipc_getref from int to bool
  ipc/util.c: further variable name cleanups
  ipc: simplify ipc initialization
  ipc: get rid of ids->tables_initialized hack
  lib/rhashtable: guarantee initial hashtable allocation
  lib/rhashtable: simplify bucket_table_alloc()
  ipc: drop ipc_lock()
  ipc/util.c: correct comment in ipc_obtain_object_check
  ipc: rename ipcctl_pre_down_nolock()
  ipc/util.c: use ipc_rcu_putref() for failues in ipc_addid()
  ipc: reorganize initialization of kern_ipc_perm.seq
  ipc: compute kern_ipc_perm.id under the ipc lock
  init/Kconfig: remove EXPERT from CHECKPOINT_RESTORE
  fs/sysv/inode.c: use ktime_get_real_seconds() for superblock stamp
  adfs: use timespec64 for time conversion
  kernel/sysctl.c: fix typos in comments
  drivers/rapidio/devices/rio_mport_cdev.c: remove redundant pointer md
  fork: don't copy inconsistent signal handler state to child
  signal: make get_signal() return bool
  signal: make sigkill_pending() return bool
  ...
2018-08-22 12:34:08 -07:00
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
Paul Menzel
3f5c15d8a7 init/main.c: log init process file name
Add a log message to `run_init_process()`.

This log message serves two purposes.

1.  If the init process is not specified on the Linux Kernel command
    line, the user sees, what file was chosen.

2.  The time stamps shows exactly, when the Linux kernel handed over
    control to the init process.

Link: http://lkml.kernel.org/r/b1fc97fa-4aa9-1904-ddb5-859e78995c41@molgen.mpg.de
Signed-off-by: Paul Menzel <pmenzel@molgen.mpg.de>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
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
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
Luc Van Oostenryck
6ad018e3ca init/: remove ineffective sparse disabling
Sparse checking used to be disabled on init/do_mounts.c and a few related
files because "Many of the syscalls used in this file expect some of the
arguments to be __user pointers not __kernel pointers".

However since 28128c61e ("kconfig.h: Include compiler types to avoid
missed struct attributes") the checks are, in fact, not disabled anymore
because of the more early include of "linux/compiler_types.h"

So remove the now ineffective #undefery that was done to disable these
warnings, as well as the associated comment.

Link: http://lkml.kernel.org/r/20180617115355.53799-1-luc.vanoostenryck@gmail.com
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Kees Cook <keescook@chromium.org>
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
Ard Biesheuvel
1b1eeca7e4 init: allow initcall tables to be emitted using relative references
Allow the initcall tables to be emitted using relative references that
are only half the size on 64-bit architectures and don't require fixups
at runtime on relocatable kernels.

Link: http://lkml.kernel.org/r/20180704083651.24360-5-ard.biesheuvel@linaro.org
Acked-by: James Morris <james.morris@microsoft.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: Petr Mladek <pmladek@suse.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Nicolas Pitre <nico@linaro.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22 10:52:47 -07:00
Linus Torvalds
0214f46b3a Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull core signal handling updates from Eric Biederman:
 "It was observed that a periodic timer in combination with a
  sufficiently expensive fork could prevent fork from every completing.
  This contains the changes to remove the need for that restart.

  This set of changes is split into several parts:

   - The first part makes PIDTYPE_TGID a proper pid type instead
     something only for very special cases. The part starts using
     PIDTYPE_TGID enough so that in __send_signal where signals are
     actually delivered we know if the signal is being sent to a a group
     of processes or just a single process.

   - With that prep work out of the way the logic in fork is modified so
     that fork logically makes signals received while it is running
     appear to be received after the fork completes"

* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (22 commits)
  signal: Don't send signals to tasks that don't exist
  signal: Don't restart fork when signals come in.
  fork: Have new threads join on-going signal group stops
  fork: Skip setting TIF_SIGPENDING in ptrace_init_task
  signal: Add calculate_sigpending()
  fork: Unconditionally exit if a fatal signal is pending
  fork: Move and describe why the code examines PIDNS_ADDING
  signal: Push pid type down into complete_signal.
  signal: Push pid type down into __send_signal
  signal: Push pid type down into send_signal
  signal: Pass pid type into do_send_sig_info
  signal: Pass pid type into send_sigio_to_task & send_sigurg_to_task
  signal: Pass pid type into group_send_sig_info
  signal: Pass pid and pid type into send_sigqueue
  posix-timers: Noralize good_sigevent
  signal: Use PIDTYPE_TGID to clearly store where file signals will be sent
  pid: Implement PIDTYPE_TGID
  pids: Move the pgrp and session pid pointers from task_struct to signal_struct
  kvm: Don't open code task_pid in kvm_vcpu_ioctl
  pids: Compute task_tgid using signal->leader_pid
  ...
2018-08-21 13:47:29 -07:00
Linus Torvalds
7140ad3898 Updates for v4.19:
- Restructure of lockdep and latency tracers
 
    This is the biggest change. Joel Fernandes restructured the hooks
    from irqs and preemption disabling and enabling. He got rid of
    a lot of the preprocessor #ifdef mess that they caused.
 
    He turned both lockdep and the latency tracers to use trace events
    inserted in the preempt/irqs disabling paths. But unfortunately,
    these started to cause issues in corner cases. Thus, parts of the
    code was reverted back to where lockde and the latency tracers
    just get called directly (without using the trace events).
    But because the original change cleaned up the code very nicely
    we kept that, as well as the trace events for preempt and irqs
    disabling, but they are limited to not being called in NMIs.
 
  - Have trace events use SRCU for "rcu idle" calls. This was required
    for the preempt/irqs off trace events. But it also had to not
    allow them to be called in NMI context. Waiting till Paul makes
    an NMI safe SRCU API.
 
  - New notrace SRCU API to allow trace events to use SRCU.
 
  - Addition of mcount-nop option support
 
  - SPDX headers replacing GPL templates.
 
  - Various other fixes and clean ups.
 
  - Some fixes are marked for stable, but were not fully tested
    before the merge window opened.
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Merge tag 'trace-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:

 - Restructure of lockdep and latency tracers

   This is the biggest change. Joel Fernandes restructured the hooks
   from irqs and preemption disabling and enabling. He got rid of a lot
   of the preprocessor #ifdef mess that they caused.

   He turned both lockdep and the latency tracers to use trace events
   inserted in the preempt/irqs disabling paths. But unfortunately,
   these started to cause issues in corner cases. Thus, parts of the
   code was reverted back to where lockdep and the latency tracers just
   get called directly (without using the trace events). But because the
   original change cleaned up the code very nicely we kept that, as well
   as the trace events for preempt and irqs disabling, but they are
   limited to not being called in NMIs.

 - Have trace events use SRCU for "rcu idle" calls. This was required
   for the preempt/irqs off trace events. But it also had to not allow
   them to be called in NMI context. Waiting till Paul makes an NMI safe
   SRCU API.

 - New notrace SRCU API to allow trace events to use SRCU.

 - Addition of mcount-nop option support

 - SPDX headers replacing GPL templates.

 - Various other fixes and clean ups.

 - Some fixes are marked for stable, but were not fully tested before
   the merge window opened.

* tag 'trace-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (44 commits)
  tracing: Fix SPDX format headers to use C++ style comments
  tracing: Add SPDX License format tags to tracing files
  tracing: Add SPDX License format to bpf_trace.c
  blktrace: Add SPDX License format header
  s390/ftrace: Add -mfentry and -mnop-mcount support
  tracing: Add -mcount-nop option support
  tracing: Avoid calling cc-option -mrecord-mcount for every Makefile
  tracing: Handle CC_FLAGS_FTRACE more accurately
  Uprobe: Additional argument arch_uprobe to uprobe_write_opcode()
  Uprobes: Simplify uprobe_register() body
  tracepoints: Free early tracepoints after RCU is initialized
  uprobes: Use synchronize_rcu() not synchronize_sched()
  tracing: Fix synchronizing to event changes with tracepoint_synchronize_unregister()
  ftrace: Remove unused pointer ftrace_swapper_pid
  tracing: More reverting of "tracing: Centralize preemptirq tracepoints and unify their usage"
  tracing/irqsoff: Handle preempt_count for different configs
  tracing: Partial revert of "tracing: Centralize preemptirq tracepoints and unify their usage"
  tracing: irqsoff: Account for additional preempt_disable
  trace: Use rcu_dereference_raw for hooks from trace-event subsystem
  tracing/kprobes: Fix within_notrace_func() to check only notrace functions
  ...
2018-08-20 18:32:00 -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
Linus Torvalds
13e091b6dd Merge branch 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 timer updates from Thomas Gleixner:
 "Early TSC based time stamping to allow better boot time analysis.

  This comes with a general cleanup of the TSC calibration code which
  grew warts and duct taping over the years and removes 250 lines of
  code. Initiated and mostly implemented by Pavel with help from various
  folks"

* 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits)
  x86/kvmclock: Mark kvm_get_preset_lpj() as __init
  x86/tsc: Consolidate init code
  sched/clock: Disable interrupts when calling generic_sched_clock_init()
  timekeeping: Prevent false warning when persistent clock is not available
  sched/clock: Close a hole in sched_clock_init()
  x86/tsc: Make use of tsc_calibrate_cpu_early()
  x86/tsc: Split native_calibrate_cpu() into early and late parts
  sched/clock: Use static key for sched_clock_running
  sched/clock: Enable sched clock early
  sched/clock: Move sched clock initialization and merge with generic clock
  x86/tsc: Use TSC as sched clock early
  x86/tsc: Initialize cyc2ns when tsc frequency is determined
  x86/tsc: Calibrate tsc only once
  ARM/time: Remove read_boot_clock64()
  s390/time: Remove read_boot_clock64()
  timekeeping: Default boot time offset to local_clock()
  timekeeping: Replace read_boot_clock64() with read_persistent_wall_and_boot_offset()
  s390/time: Add read_persistent_wall_and_boot_offset()
  x86/xen/time: Output xen sched_clock time from 0
  x86/xen/time: Initialize pv xen time in init_hypervisor_platform()
  ...
2018-08-13 18:28:19 -07:00
Linus Torvalds
eac3411944 Merge branch 'x86/pti' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 PTI updates from Thomas Gleixner:
 "The Speck brigade sadly provides yet another large set of patches
  destroying the perfomance which we carefully built and preserved

   - PTI support for 32bit PAE. The missing counter part to the 64bit
     PTI code implemented by Joerg.

   - A set of fixes for the Global Bit mechanics for non PCID CPUs which
     were setting the Global Bit too widely and therefore possibly
     exposing interesting memory needlessly.

   - Protection against userspace-userspace SpectreRSB

   - Support for the upcoming Enhanced IBRS mode, which is preferred
     over IBRS. Unfortunately we dont know the performance impact of
     this, but it's expected to be less horrible than the IBRS
     hammering.

   - Cleanups and simplifications"

* 'x86/pti' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (60 commits)
  x86/mm/pti: Move user W+X check into pti_finalize()
  x86/relocs: Add __end_rodata_aligned to S_REL
  x86/mm/pti: Clone kernel-image on PTE level for 32 bit
  x86/mm/pti: Don't clear permissions in pti_clone_pmd()
  x86/mm/pti: Fix 32 bit PCID check
  x86/mm/init: Remove freed kernel image areas from alias mapping
  x86/mm/init: Add helper for freeing kernel image pages
  x86/mm/init: Pass unconverted symbol addresses to free_init_pages()
  mm: Allow non-direct-map arguments to free_reserved_area()
  x86/mm/pti: Clear Global bit more aggressively
  x86/speculation: Support Enhanced IBRS on future CPUs
  x86/speculation: Protect against userspace-userspace spectreRSB
  x86/kexec: Allocate 8k PGDs for PTI
  Revert "perf/core: Make sure the ring-buffer is mapped in all page-tables"
  x86/mm: Remove in_nmi() warning from vmalloc_fault()
  x86/entry/32: Check for VM86 mode in slow-path check
  perf/core: Make sure the ring-buffer is mapped in all page-tables
  x86/pti: Check the return value of pti_user_pagetable_walk_pmd()
  x86/pti: Check the return value of pti_user_pagetable_walk_p4d()
  x86/entry/32: Add debug code to check entry/exit CR3
  ...
2018-08-13 17:54:17 -07:00
Linus Torvalds
b5b1404d08 init: rename and re-order boot_cpu_state_init()
This is purely a preparatory patch for upcoming changes during the 4.19
merge window.

We have a function called "boot_cpu_state_init()" that isn't really
about the bootup cpu state: that is done much earlier by the similarly
named "boot_cpu_init()" (note lack of "state" in name).

This function initializes some hotplug CPU state, and needs to run after
the percpu data has been properly initialized.  It even has a comment to
that effect.

Except it _doesn't_ actually run after the percpu data has been properly
initialized.  On x86 it happens to do that, but on at least arm and
arm64, the percpu base pointers are initialized by the arch-specific
'smp_prepare_boot_cpu()' hook, which ran _after_ boot_cpu_state_init().

This had some unexpected results, and in particular we have a patch
pending for the merge window that did the obvious cleanup of using
'this_cpu_write()' in the cpu hotplug init code:

  -       per_cpu_ptr(&cpuhp_state, smp_processor_id())->state = CPUHP_ONLINE;
  +       this_cpu_write(cpuhp_state.state, CPUHP_ONLINE);

which is obviously the right thing to do.  Except because of the
ordering issue, it actually failed miserably and unexpectedly on arm64.

So this just fixes the ordering, and changes the name of the function to
be 'boot_cpu_hotplug_init()' to make it obvious that it's about cpu
hotplug state, because the core CPU state was supposed to have already
been done earlier.

Marked for stable, since the (not yet merged) patch that will show this
problem is marked for stable.

Reported-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-12 12:19:42 -07:00
Steven Rostedt (VMware)
bff1b208a5 tracing: Partial revert of "tracing: Centralize preemptirq tracepoints and unify their usage"
Joel Fernandes created a nice patch that cleaned up the duplicate hooks used
by lockdep and irqsoff latency tracer. It made both use tracepoints. But it
caused lockdep to trigger several false positives. We have not figured out
why yet, but removing lockdep from using the trace event hooks and just call
its helper functions directly (like it use to), makes the problem go away.

This is a partial revert of the clean up patch c3bc8fd637 ("tracing:
Centralize preemptirq tracepoints and unify their usage") that adds direct
calls for lockdep, but also keeps most of the clean up done to get rid of
the horrible preprocessor if statements.

Link: http://lkml.kernel.org/r/20180806155058.5ee875f4@gandalf.local.home

Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Fixes: c3bc8fd637 ("tracing: Centralize preemptirq tracepoints and unify their usage")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-10 15:11:25 -04:00
Eric W. Biederman
c3ad2c3b02 signal: Don't restart fork when signals come in.
Wen Yang <wen.yang99@zte.com.cn> and majiang <ma.jiang@zte.com.cn>
report that a periodic signal received during fork can cause fork to
continually restart preventing an application from making progress.

The code was being overly pessimistic.  Fork needs to guarantee that a
signal sent to multiple processes is logically delivered before the
fork and just to the forking process or logically delivered after the
fork to both the forking process and it's newly spawned child.  For
signals like periodic timers that are always delivered to a single
process fork can safely complete and let them appear to logically
delivered after the fork().

While examining this issue I also discovered that fork today will miss
signals delivered to multiple processes during the fork and handled by
another thread.  Similarly the current code will also miss blocked
signals that are delivered to multiple process, as those signals will
not appear pending during fork.

Add a list of each thread that is currently forking, and keep on that
list a signal set that records all of the signals sent to multiple
processes.  When fork completes initialize the new processes
shared_pending signal set with it.  The calculate_sigpending function
will see those signals and set TIF_SIGPENDING causing the new task to
take the slow path to userspace to handle those signals.  Making it
appear as if those signals were received immediately after the fork.

It is not possible to send real time signals to multiple processes and
exceptions don't go to multiple processes, which means that that are
no signals sent to multiple processes that require siginfo.  This
means it is safe to not bother collecting siginfo on signals sent
during fork.

The sigaction of a child of fork is initially the same as the
sigaction of the parent process.  So a signal the parent ignores the
child will also initially ignore.  Therefore it is safe to ignore
signals sent to multiple processes and ignored by the forking process.

Signals sent to only a single process or only a single thread and delivered
during fork are treated as if they are received after the fork, and generally
not dealt with.  They won't cause any problems.

V2: Added removal from the multiprocess list on failure.
V3: Use -ERESTARTNOINTR directly
V4: - Don't queue both SIGCONT and SIGSTOP
    - Initialize signal_struct.multiprocess in init_task
    - Move setting of shared_pending to before the new task
      is visible to signals.  This prevents signals from comming
      in before shared_pending.signal is set to delayed.signal
      and being lost.
V5: - rework list add and delete to account for idle threads
v6: - Use sigdelsetmask when removing stop signals

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=200447
Reported-by: Wen Yang <wen.yang99@zte.com.cn> and
Reported-by: majiang <ma.jiang@zte.com.cn>
Fixes: 4a2c7a7837 ("[PATCH] make fork() atomic wrt pgrp/session signals")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-08-09 13:07:01 -05:00
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
Joel Fernandes (Google)
c3bc8fd637 tracing: Centralize preemptirq tracepoints and unify their usage
This patch detaches the preemptirq tracepoints from the tracers and
keeps it separate.

Advantages:
* Lockdep and irqsoff event can now run in parallel since they no longer
have their own calls.

* This unifies the usecase of adding hooks to an irqsoff and irqson
event, and a preemptoff and preempton event.
  3 users of the events exist:
  - Lockdep
  - irqsoff and preemptoff tracers
  - irqs and preempt trace events

The unification cleans up several ifdefs and makes the code in preempt
tracer and irqsoff tracers simpler. It gets rid of all the horrific
ifdeferry around PROVE_LOCKING and makes configuration of the different
users of the tracepoints more easy and understandable. It also gets rid
of the time_* function calls from the lockdep hooks used to call into
the preemptirq tracer which is not needed anymore. The negative delta in
lines of code in this patch is quite large too.

In the patch we introduce a new CONFIG option PREEMPTIRQ_TRACEPOINTS
as a single point for registering probes onto the tracepoints. With
this,
the web of config options for preempt/irq toggle tracepoints and its
users becomes:

 PREEMPT_TRACER   PREEMPTIRQ_EVENTS  IRQSOFF_TRACER PROVE_LOCKING
       |                 |     \         |           |
       \    (selects)    /      \        \ (selects) /
      TRACE_PREEMPT_TOGGLE       ----> TRACE_IRQFLAGS
                      \                  /
                       \ (depends on)   /
                     PREEMPTIRQ_TRACEPOINTS

Other than the performance tests mentioned in the previous patch, I also
ran the locking API test suite. I verified that all tests cases are
passing.

I also injected issues by not registering lockdep probes onto the
tracepoints and I see failures to confirm that the probes are indeed
working.

This series + lockdep probes not registered (just to inject errors):
[    0.000000]      hard-irqs-on + irq-safe-A/21:  ok  |  ok  |  ok  |
[    0.000000]      soft-irqs-on + irq-safe-A/21:  ok  |  ok  |  ok  |
[    0.000000]        sirq-safe-A => hirqs-on/12:FAILED|FAILED|  ok  |
[    0.000000]        sirq-safe-A => hirqs-on/21:FAILED|FAILED|  ok  |
[    0.000000]          hard-safe-A + irqs-on/12:FAILED|FAILED|  ok  |
[    0.000000]          soft-safe-A + irqs-on/12:FAILED|FAILED|  ok  |
[    0.000000]          hard-safe-A + irqs-on/21:FAILED|FAILED|  ok  |
[    0.000000]          soft-safe-A + irqs-on/21:FAILED|FAILED|  ok  |
[    0.000000]     hard-safe-A + unsafe-B #1/123:  ok  |  ok  |  ok  |
[    0.000000]     soft-safe-A + unsafe-B #1/123:  ok  |  ok  |  ok  |

With this series + lockdep probes registered, all locking tests pass:

[    0.000000]      hard-irqs-on + irq-safe-A/21:  ok  |  ok  |  ok  |
[    0.000000]      soft-irqs-on + irq-safe-A/21:  ok  |  ok  |  ok  |
[    0.000000]        sirq-safe-A => hirqs-on/12:  ok  |  ok  |  ok  |
[    0.000000]        sirq-safe-A => hirqs-on/21:  ok  |  ok  |  ok  |
[    0.000000]          hard-safe-A + irqs-on/12:  ok  |  ok  |  ok  |
[    0.000000]          soft-safe-A + irqs-on/12:  ok  |  ok  |  ok  |
[    0.000000]          hard-safe-A + irqs-on/21:  ok  |  ok  |  ok  |
[    0.000000]          soft-safe-A + irqs-on/21:  ok  |  ok  |  ok  |
[    0.000000]     hard-safe-A + unsafe-B #1/123:  ok  |  ok  |  ok  |
[    0.000000]     soft-safe-A + unsafe-B #1/123:  ok  |  ok  |  ok  |

Link: http://lkml.kernel.org/r/20180730222423.196630-4-joel@joelfernandes.org

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-31 11:32:27 -04:00
Eric W. Biederman
6883f81aac pid: Implement PIDTYPE_TGID
Everywhere except in the pid array we distinguish between a tasks pid and
a tasks tgid (thread group id).  Even in the enumeration we want that
distinction sometimes so we have added __PIDTYPE_TGID.  With leader_pid
we almost have an implementation of PIDTYPE_TGID in struct signal_struct.

Add PIDTYPE_TGID as a first class member of the pid_type enumeration and
into the pids array.  Then remove the __PIDTYPE_TGID special case and the
leader_pid in signal_struct.

The net size increase is just an extra pointer added to struct pid and
an extra pair of pointers of an hlist_node added to task_struct.

The effect on code maintenance is the removal of a number of special
cases today and the potential to remove many more special cases as
PIDTYPE_TGID gets used to it's fullest.  The long term potential
is allowing zombie thread group leaders to exit, which will remove
a lot more special cases in the code.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-07-21 10:43:12 -05:00
Eric W. Biederman
2c4704756c pids: Move the pgrp and session pid pointers from task_struct to signal_struct
To access these fields the code always has to go to group leader so
going to signal struct is no loss and is actually a fundamental simplification.

This saves a little bit of memory by only allocating the pid pointer array
once instead of once for every thread, and even better this removes a
few potential races caused by the fact that group_leader can be changed
by de_thread, while signal_struct can not.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-07-21 10:43:12 -05:00
Eric W. Biederman
2896b0f09f pids: Initialize leader_pid in init_task
This is cheap and no cost so we might as well.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-07-21 10:43:12 -05:00
Joerg Roedel
b976690f5d x86/mm/pti: Introduce pti_finalize()
Introduce a new function to finalize the kernel mappings for the userspace
page-table after all ro/nx protections have been applied to the kernel
mappings.

Also move the call to pti_clone_kernel_text() to that function so that it
will run on 32 bit kernels too.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Pavel Machek <pavel@ucw.cz>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: linux-mm@kvack.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Waiman Long <llong@redhat.com>
Cc: "David H . Gutteridge" <dhgutteridge@sympatico.ca>
Cc: joro@8bytes.org
Link: https://lkml.kernel.org/r/1531906876-13451-30-git-send-email-joro@8bytes.org
2018-07-20 01:11:45 +02:00
Pavel Tatashin
857baa87b6 sched/clock: Enable sched clock early
Allow sched_clock() to be used before schec_clock_init() is called.  This
provides a way to get early boot timestamps on machines with unstable
clocks.

Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: peterz@infradead.org
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20180719205545.16512-24-pasha.tatashin@oracle.com
2018-07-20 00:02:43 +02:00
Pavel Tatashin
5d2a4e91a5 sched/clock: Move sched clock initialization and merge with generic clock
sched_clock_postinit() initializes a generic clock on systems where no
other clock is provided. This function may be called only after
timekeeping_init().

Rename sched_clock_postinit to generic_clock_inti() and call it from
sched_clock_init(). Move the call for sched_clock_init() until after
time_init().

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: steven.sistare@oracle.com
Cc: daniel.m.jordan@oracle.com
Cc: linux@armlinux.org.uk
Cc: schwidefsky@de.ibm.com
Cc: heiko.carstens@de.ibm.com
Cc: john.stultz@linaro.org
Cc: sboyd@codeaurora.org
Cc: hpa@zytor.com
Cc: douly.fnst@cn.fujitsu.com
Cc: prarit@redhat.com
Cc: feng.tang@intel.com
Cc: pmladek@suse.com
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: linux-s390@vger.kernel.org
Cc: boris.ostrovsky@oracle.com
Cc: jgross@suse.com
Cc: pbonzini@redhat.com
Link: https://lkml.kernel.org/r/20180719205545.16512-23-pasha.tatashin@oracle.com
2018-07-20 00:02:43 +02:00
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
8b5c6a3a49 audit/stable-4.18 PR 20180605
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Merge tag 'audit-pr-20180605' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit

Pull audit updates from Paul Moore:
 "Another reasonable chunk of audit changes for v4.18, thirteen patches
  in total.

  The thirteen patches can mostly be broken down into one of four
  categories: general bug fixes, accessor functions for audit state
  stored in the task_struct, negative filter matches on executable
  names, and extending the (relatively) new seccomp logging knobs to the
  audit subsystem.

  The main driver for the accessor functions from Richard are the
  changes we're working on to associate audit events with containers,
  but I think they have some standalone value too so I figured it would
  be good to get them in now.

  The seccomp/audit patches from Tyler apply the seccomp logging
  improvements from a few releases ago to audit's seccomp logging;
  starting with this patchset the changes in
  /proc/sys/kernel/seccomp/actions_logged should apply to both the
  standard kernel logging and audit.

  As usual, everything passes the audit-testsuite and it happens to
  merge cleanly with your tree"

[ Heh, except it had trivial merge conflicts with the SELinux tree that
  also came in from Paul   - Linus ]

* tag 'audit-pr-20180605' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
  audit: Fix wrong task in comparison of session ID
  audit: use existing session info function
  audit: normalize loginuid read access
  audit: use new audit_context access funciton for seccomp_actions_logged
  audit: use inline function to set audit context
  audit: use inline function to get audit context
  audit: convert sessionid unset to a macro
  seccomp: Don't special case audited processes when logging
  seccomp: Audit attempts to modify the actions_logged sysctl
  seccomp: Configurable separator for the actions_logged string
  seccomp: Separate read and write code for actions_logged sysctl
  audit: allow not equal op for audit by executable
  audit: add syscall information to FEATURE_CHANGE records
2018-06-06 16:34:00 -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