Commit graph

22582 commits

Author SHA1 Message Date
Al Viro
369796a884 fix memory leaks in tracing_buffers_splice_read()
commit 1ae2293dd6d2f5c823cf97e60b70d03631cd622f upstream.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-30 10:18:38 +02:00
Steven Rostedt
a52031beb0 Makefile: Mute warning for __builtin_return_address(>0) for tracing only
commit 377ccbb483738f84400ddf5840c7dd8825716985 upstream.

With the latest gcc compilers, they give a warning if
__builtin_return_address() parameter is greater than 0. That is because if
it is used by a function called by a top level function (or in the case of
the kernel, by assembly), it can try to access stack frames outside the
stack and crash the system.

The tracing system uses __builtin_return_address() of up to 2! But it is
well aware of the dangers that it may have, and has even added precautions
to protect against it (see the thunk code in arch/x86/entry/thunk*.S)

Linus originally added KBUILD_CFLAGS that would suppress the warning for the
entire kernel, as simply adding KBUILD_CFLAGS to the tracing directory
wouldn't work. The tracing directory plays a bit with the CFLAGS and
requires a little more logic.

This adds that special logic to only suppress the warning for the tracing
directory. If it is used anywhere else outside of tracing, the warning will
still be triggered.

Link: http://lkml.kernel.org/r/20160728223043.51996267@grimm.local.home

Tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-30 10:18:35 +02:00
Arnd Bergmann
29bd03596e Fix build warning in kernel/cpuset.c
>           2 ../kernel/cpuset.c:2101:11: warning: initialization from incompatible pointer type [-Wincompatible-pointer-types]
>           1 ../kernel/cpuset.c:2101:2: warning: initialization from incompatible pointer type
>           1 ../kernel/cpuset.c:2101:2: warning: (near initialization for 'cpuset_cgrp_subsys.fork')

This got introduced by 06ec7a1d76 ("cpuset: make sure new tasks
conform to the current config of the cpuset"). In the upstream
kernel, the function prototype was changed as of b53202e63089
("cgroup: kill cgrp_ss_priv[CGROUP_CANFORK_COUNT] and friends").

That patch is not suitable for stable kernels, and fortunately
the warning seems harmless as the prototypes only differ in the
second argument that is unused. Adding that argument gets rid
of the warning:

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-30 10:18:33 +02:00
Linux Build Service Account
f6d68e27bf Merge "sched: constrain HMP scheduler tunable range with in better way" 2016-09-29 11:20:30 -07:00
Linux Build Service Account
95ce9d98db Merge "sched/core_ctl: Integrate core control with cpu isolation" 2016-09-29 11:20:17 -07:00
Linux Build Service Account
461424e5ec Merge "sched/core_ctl: Refactor cpu data" 2016-09-29 11:20:17 -07:00
Linux Build Service Account
bbf8724641 Merge "core_ctrl: Move core control into kernel" 2016-09-29 11:20:17 -07:00
Pavankumar Kondeti
9d128dbca3 sched: don't assume higher capacity means higher power in lb
The load balancer restrictions are in place to control the tasks
migration from the lower capacity cluster to higher capacity
cluster to save power. The assumption here is that higher capacity
cluster will have higher power cost which may not be necessarily
true for all platforms. Use power cost based checks instead of
capacity based checks while applying the inter cluster migration
restrictions.

Change-Id: Id9519eb8f7b183a2e9fca87a23cf95e951aa4005
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
2016-09-29 10:07:19 +05:30
Olav Haugan
e42aae958b sched/core_ctl: Integrate core control with cpu isolation
Replace hotplug functionality in core control with cpu isolation
and integrate into scheduler.

Change-Id: I4f1514ba5bac2e259a1105fcafb31d6a92ddd249
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-24 11:00:06 -07:00
Olav Haugan
e7c8de6756 sched/core_ctl: Refactor cpu data
Refactor cpu data into cpu data and cluster data to improve readability and
ease of understanding the code.

Change-Id: I96505aeb9d07a6fa3a2c28648ffa299e0cfa2e41
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-24 11:00:05 -07:00
Olav Haugan
5d1e98d51d trace: Move core control trace events to scheduler
Move the core control trace events to scheduler trace event file.

Change-Id: I65943d8e4a9eac1f9f5a40ad5aaf166679215f48
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-24 11:00:04 -07:00
Olav Haugan
59f16ae034 core_ctrl: Move core control into kernel
Move core control from out-of-tree module into the kernel proper.

Core control monitors load on CPUs and controls how many CPUs are
available for the system to use at any point in time. This can help save
power. Core control can be configured through sysfs interface.

Change-Id: Ia78e701468ea3828195c2a15c9cf9fafd099804a
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-24 11:00:03 -07:00
Olav Haugan
7f2c523643 core_ctl_helper: Remove code since it is not used anymore
Remove the core control helper code since this is not needed anymore
with subsequent patches that moves core control into the kernel.

Change-Id: I62acddeb707fc7d5626580166b3466e63f45fd89
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-24 11:00:02 -07:00
Olav Haugan
639c8ad52d perf: Add cpu isolation awareness
Ensure perf events does not wake up idle cores when core is isolated.

Change-Id: Ifefb2f1cf6c24af7bc46fc62797955b8c8ad5815
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-24 10:59:59 -07:00
Olav Haugan
e38c1ce123 smp: Do not wake up all idle CPUs
Do not wake up cpus that are isolated.

Change-Id: I07702bb5b738c1c75c49a2ca4cb08be0231ccb12
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-24 10:59:58 -07:00
Olav Haugan
bc24c063ef pmqos: Enable cpu isolation awareness
Set long latency requirement for isolated cores to ensure LPM logic will
select a deep sleep state.

Change-Id: I83e9fbb800df259616a145d311b50627dc42a5ff
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-24 10:59:57 -07:00
Olav Haugan
4400ef145f irq: Make irq affinity function cpu isolation aware
Prohibit setting the affinity of an IRQ to an isolated core.

Change-Id: I7b50778615541a64f9956573757c7f28748c4f69
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-24 10:59:55 -07:00
Olav Haugan
0a17b36a20 sched/core: Add trace point for cpu isolation
Add tracepoint to capture the cpu isolation event including KPI for
time it took to isolate.

Change-Id: If2d30000f068afc50db953940f4636ef6a089b24
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-24 10:59:42 -07:00
Olav Haugan
e33c24bfec sched: add cpu isolation support
This adds cpu isolation APIs to the scheduler to isolate and unisolate
CPUs. Isolating and unisolating a CPU can be used in place of hotplug.
Isolating and unisolating a CPU is faster than hotplug and can thus be
used to optimize the performance and power of multi-core CPUs.

Isolating works by migrating non-pinned IRQs and tasks to other CPUS and
marking the CPU as not available to the scheduler and load balancer.
Pinned tasks and IRQs are still allowed to run but it is expected that
this would be minimal.

Unisolation works by just marking the CPU available for scheduler and
load balancer.

Change-Id: I0bbddb56238c2958c5987877c5bfc3e79afa67cc
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-24 10:55:17 -07:00
Linux Build Service Account
a7186f9754 Merge "cgroup: make sure a parent css isn't freed before its children" 2016-09-24 02:00:29 -07:00
Thomas Gleixner
2fbc61d977 genirq/msi: Fix broken debug output
commit 4364e1a29be16b2783c0bcbc263f61236af64281 upstream.

virq is not required to be the same for all msi descs. Use the base irq number
from the desc in the debug printk.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-24 10:07:46 +02:00
Arnd Bergmann
268a8bf90e kconfig: tinyconfig: provide whole choice blocks to avoid warnings
commit 236dec051078a8691950f56949612b4b74107e48 upstream.

Using "make tinyconfig" produces a couple of annoying warnings that show
up for build test machines all the time:

    .config:966:warning: override: NOHIGHMEM changes choice state
    .config:965:warning: override: SLOB changes choice state
    .config:963:warning: override: KERNEL_XZ changes choice state
    .config:962:warning: override: CC_OPTIMIZE_FOR_SIZE changes choice state
    .config:933:warning: override: SLOB changes choice state
    .config:930:warning: override: CC_OPTIMIZE_FOR_SIZE changes choice state
    .config:870:warning: override: SLOB changes choice state
    .config:868:warning: override: KERNEL_XZ changes choice state
    .config:867:warning: override: CC_OPTIMIZE_FOR_SIZE changes choice state

I've made a previous attempt at fixing them and we discussed a number of
alternatives.

I tried changing the Makefile to use "merge_config.sh -n
$(fragment-list)" but couldn't get that to work properly.

This is yet another approach, based on the observation that we do want
to see a warning for conflicting 'choice' options, and that we can
simply make them non-conflicting by listing all other options as
disabled.  This is a trivial patch that we can apply independent of
plans for other changes.

Link: http://lkml.kernel.org/r/20160829214952.1334674-2-arnd@arndb.de
Link: https://storage.kernelci.org/mainline/v4.7-rc6/x86-tinyconfig/build.log
https://patchwork.kernel.org/patch/9212749/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-24 10:07:42 +02:00
Balbir Singh
a37a538e82 sched/core: Fix a race between try_to_wake_up() and a woken up task
commit 135e8c9250dd5c8c9aae5984fde6f230d0cbfeaf upstream.

The origin of the issue I've seen is related to
a missing memory barrier between check for task->state and
the check for task->on_rq.

The task being woken up is already awake from a schedule()
and is doing the following:

	do {
		schedule()
		set_current_state(TASK_(UN)INTERRUPTIBLE);
	} while (!cond);

The waker, actually gets stuck doing the following in
try_to_wake_up():

	while (p->on_cpu)
		cpu_relax();

Analysis:

The instance I've seen involves the following race:

 CPU1					CPU2

 while () {
   if (cond)
     break;
   do {
     schedule();
     set_current_state(TASK_UN..)
   } while (!cond);
					wakeup_routine()
					  spin_lock_irqsave(wait_lock)
   raw_spin_lock_irqsave(wait_lock)	  wake_up_process()
 }					  try_to_wake_up()
 set_current_state(TASK_RUNNING);	  ..
 list_del(&waiter.list);

CPU2 wakes up CPU1, but before it can get the wait_lock and set
current state to TASK_RUNNING the following occurs:

 CPU3
 wakeup_routine()
 raw_spin_lock_irqsave(wait_lock)
 if (!list_empty)
   wake_up_process()
   try_to_wake_up()
   raw_spin_lock_irqsave(p->pi_lock)
   ..
   if (p->on_rq && ttwu_wakeup())
   ..
   while (p->on_cpu)
     cpu_relax()
   ..

CPU3 tries to wake up the task on CPU1 again since it finds
it on the wait_queue, CPU1 is spinning on wait_lock, but immediately
after CPU2, CPU3 got it.

CPU3 checks the state of p on CPU1, it is TASK_UNINTERRUPTIBLE and
the task is spinning on the wait_lock. Interestingly since p->on_rq
is checked under pi_lock, I've noticed that try_to_wake_up() finds
p->on_rq to be 0. This was the most confusing bit of the analysis,
but p->on_rq is changed under runqueue lock, rq_lock, the p->on_rq
check is not reliable without this fix IMHO. The race is visible
(based on the analysis) only when ttwu_queue() does a remote wakeup
via ttwu_queue_remote. In which case the p->on_rq change is not
done uder the pi_lock.

The result is that after a while the entire system locks up on
the raw_spin_irqlock_save(wait_lock) and the holder spins infintely

Reproduction of the issue:

The issue can be reproduced after a long run on my system with 80
threads and having to tweak available memory to very low and running
memory stress-ng mmapfork test. It usually takes a long time to
reproduce. I am trying to work on a test case that can reproduce
the issue faster, but thats work in progress. I am still testing the
changes on my still in a loop and the tests seem OK thus far.

Big thanks to Benjamin and Nick for helping debug this as well.
Ben helped catch the missing barrier, Nick caught every missing
bit in my theory.

Signed-off-by: Balbir Singh <bsingharora@gmail.com>
[ Updated comment to clarify matching barriers. Many
  architectures do not have a full barrier in switch_to()
  so that cannot be relied upon. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Alexey Kardashevskiy <aik@ozlabs.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nicholas Piggin <nicholas.piggin@gmail.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/e02cce7b-d9ca-1ad0-7a61-ea97c7582b37@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-24 10:07:42 +02:00
Zefan Li
06ec7a1d76 cpuset: make sure new tasks conform to the current config of the cpuset
commit 06f4e94898918bcad00cdd4d349313a439d6911e upstream.

A new task inherits cpus_allowed and mems_allowed masks from its parent,
but if someone changes cpuset's config by writing to cpuset.cpus/cpuset.mems
before this new task is inserted into the cgroup's task list, the new task
won't be updated accordingly.

Signed-off-by: Zefan Li <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-24 10:07:39 +02:00
Mateusz Guzik
d0259cc85b audit: fix exe_file access in audit_exe_compare
commit 5efc244346f9f338765da3d592f7947b0afdc4b5 upstream.

Prior to the change the function would blindly deference mm, exe_file
and exe_file->f_inode, each of which could have been NULL or freed.

Use get_task_exe_file to safely obtain stable exe_file.

Signed-off-by: Mateusz Guzik <mguzik@redhat.com>
Acked-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Acked-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-24 10:07:36 +02:00
Mateusz Guzik
f750847daa mm: introduce get_task_exe_file
commit cd81a9170e69e018bbaba547c1fd85a585f5697a upstream.

For more convenient access if one has a pointer to the task.

As a minor nit take advantage of the fact that only task lock + rcu are
needed to safely grab ->exe_file. This saves mm refcount dance.

Use the helper in proc_exe_link.

Signed-off-by: Mateusz Guzik <mguzik@redhat.com>
Acked-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Acked-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-24 10:07:36 +02:00
Thiago Jung Bauermann
0d57cbc66b kexec: fix double-free when failing to relocate the purgatory
commit 070c43eea5043e950daa423707ae3c77e2f48edb upstream.

If kexec_apply_relocations fails, kexec_load_purgatory frees pi->sechdrs
and pi->purgatory_buf.  This is redundant, because in case of error
kimage_file_prepare_segments calls kimage_file_post_load_cleanup, which
will also free those buffers.

This causes two warnings like the following, one for pi->sechdrs and the
other for pi->purgatory_buf:

  kexec-bzImage64: Loading purgatory failed
  ------------[ cut here ]------------
  WARNING: CPU: 1 PID: 2119 at mm/vmalloc.c:1490 __vunmap+0xc1/0xd0
  Trying to vfree() nonexistent vm area (ffffc90000e91000)
  Modules linked in:
  CPU: 1 PID: 2119 Comm: kexec Not tainted 4.8.0-rc3+ #5
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
  Call Trace:
    dump_stack+0x4d/0x65
    __warn+0xcb/0xf0
    warn_slowpath_fmt+0x4f/0x60
    ? find_vmap_area+0x19/0x70
    ? kimage_file_post_load_cleanup+0x47/0xb0
    __vunmap+0xc1/0xd0
    vfree+0x2e/0x70
    kimage_file_post_load_cleanup+0x5e/0xb0
    SyS_kexec_file_load+0x448/0x680
    ? putname+0x54/0x60
    ? do_sys_open+0x190/0x1f0
    entry_SYSCALL_64_fastpath+0x13/0x8f
  ---[ end trace 158bb74f5950ca2b ]---

Fix by setting pi->sechdrs an pi->purgatory_buf to NULL, since vfree
won't try to free a NULL pointer.

Link: http://lkml.kernel.org/r/1472083546-23683-1-git-send-email-bauerman@linux.vnet.ibm.com
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-24 10:07:36 +02:00
Joonwoo Park
cc60f0790f sched: constrain HMP scheduler tunable range with in better way
HMP scheduler tunables can be constrained via extra1 and extra2 of
ctl_table.  Having valid range in the sysctl table gives clearer
view of tunable's range.

Also add range for sched_select_prev_cpu_us so we can avoid invalid
value configuration of that tunable.

CRs-fixed: 1056910
Change-Id: I09fcc019133f4d37b7be3287da8e0733e40fc0ac
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
2016-09-21 16:50:42 -07:00
Olav Haugan
3fe956359c watchdog: Add support for cpu isolation
Open up interface to allow external subsystem to enable and disable hard
lockup detector.

Change-Id: I88a728ee1d54aaa887fab52e5e40d1d4e4fc69ca
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-20 17:47:13 -07:00
Olav Haugan
fc70615291 cpumask: Add cpu isolation support
Add bitmask and corresponding supporting functions for cpu isolation.

Change-Id: Ice1a9503666a2b720bdb324289ca55ceb33097cd
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-20 17:47:13 -07:00
Olav Haugan
922fed628c timer: Do not require CPUSETS to be enabled for migration
Do not require CPUSETS to be enabled to allow migration of timers and
hrtimers.

Change-Id: Ib911a0d34c250c4df020bdb265b92d2b8df8db93
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-20 17:47:13 -07:00
Santosh Shukla
bba552f4fc timer: Add function to migrate timers
Add function to migrate timer that will be used by later patch set.

Change-Id: I370e404001344e635a663822b07557abbe0f6f52
Signed-off-by: Santosh Shukla <santosh.shukla@linaro.org>
[ohaugan@codeaurora.org: Updated commit text and fixed trivial merge conflict]
Git-commit: 3633b88d8fcb4273807574c27c328b6908a741e5
Git-repo: git://git.linaro.org/people/mike.holmes/santosh.shukla/lng-isol.git
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-20 17:47:12 -07:00
Gary S. Robertson
84e39dcb3b hrtimer.h: prevent pinned timer state from breaking inactive test
An hrtimer may be pinned to a CPU but inactive, so it is no longer valid
to test the hrtimer.state struct member as having no bits set when inactive.
Changed the test function to mask out the HRTIMER_STATE_PINNED bit when
checking for inactive state.

Change-Id: I632f37874ef79887ee1202a028ef734f392d6ed0
Signed-off-by: Gary S. Robertson <gary.robertson@linaro.org>
[ohaugan@codeaurora.org: Port to 4.4]
Git-commit: 902e4d4eb0d2158d2792166221a72a829caecf07
Git-repo: git://git.linaro.org/people/mike.holmes/santosh.shukla/lng-isol.git
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-20 17:47:12 -07:00
Viresh Kumar
a66156c83c hrtimer: make sure PINNED flag is cleared after removing hrtimer
Change-Id: Icc4d1c183e993b4b3c9b96ec9779c234e73ecab7
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[forward port to 3.18]
Signed-off-by: Santosh Shukla <santosh.shukla@linaro.org>
Git-commit: d6c894e515b4cd93c3a08e7c60cce0aa5118c656
Git-repo: git://git.linaro.org/people/mike.holmes/santosh.shukla/lng-isol.git
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-20 17:47:12 -07:00
Viresh Kumar
f461d408ac hrtimer: create hrtimer_quiesce_cpu() to isolate CPU from hrtimers
To isolate CPUs (isolate from hrtimers) from sysfs using cpusets, we need some
support from the hrtimer core. i.e. A routine hrtimer_quiesce_cpu() which would
migrate away all the unpinned hrtimers, but shouldn't touch the pinned ones.

This patch creates this routine.

Change-Id: I51259ea41e3bd5cdba50b718201a6840174a7224
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[forward port to 3.18]
Signed-off-by: Santosh Shukla <santosh.shukla@linaro.org>
[ohaugan@codeaurora.org: Port to 4.4]
Git-commit: d4d50a0ddc35e58ee95137ba4d14e74fea8b682f
Git-repo: git://git.linaro.org/people/mike.holmes/santosh.shukla/lng-isol.git
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-20 17:47:12 -07:00
Viresh Kumar
d0cea65e27 hrtimer: update timer->state with 'pinned' information
'Pinned' information would be required in migrate_hrtimers() now, as we can
migrate non-pinned timers away without a hotplug (i.e. with cpuset.quiesce). And
so we may need to identify pinned timers now, as we can't migrate them.

This patch reuses the timer->state variable for setting this flag as there were
enough number of free bits available in this variable. And there is no point
increasing size of this struct by adding another field.

Change-Id: If3b3770e547971809e789ea7c8033c48ec2aa92d
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[forward port to 3.18]
Signed-off-by: Santosh Shukla <santosh.shukla@linaro.org>
[ohaugan@codeaurora.org: Port to 4.4]
Git-commit: 62feaf1ed0b64c04868d143d8bdb92d60dc3189b
Git-repo: git://git.linaro.org/people/mike.holmes/santosh.shukla/lng-isol.git
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-20 17:47:12 -07:00
Viresh Kumar
a7dffd7ffb timer: create timer_quiesce_cpu() to isolate CPU from timers
To isolate CPUs (isolate from timers) from sysfs using cpusets, we need some
support from the timer core. i.e. A routine timer_quiesce_cpu() which would
migrates away all the unpinned timers, but shouldn't touch the pinned ones.

This patch creates this routine.

Change-Id: I8624e0659b86b7b8fa425a3fafdb0784fe005124
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[forward port to 3.18]
Signed-off-by: Santosh Shukla <santosh.shukla@linaro.org>
[ohaugan@codeaurora.org: Port to 4.4. Fixes for compilation error]
Git-commit: 313910b70ea0c73f8789d9189c11e1f339080646
Git-repo: git://git.linaro.org/people/mike.holmes/santosh.shukla/lng-isol.git
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-20 17:47:11 -07:00
Olav Haugan
6cc98f03ad timer: Ensure timers are not running before migrating
This is needed to support migration of timers during cpu isolation. A
timer might be running on the CPU that we want to isolate so we are
unable to migrate the timers at this point. We are adding a spin-loop to
wait for the timer to finish before migrating the timers.

Change-Id: I24d6e91b6dff468c640c2fe3a37a7f31b6f0c79a
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
2016-09-20 17:47:11 -07:00
Alex Shi
5f87c475f8 Merge branch 'linux-linaro-lsk-v4.4' into linux-linaro-lsk-v4.4-android
Conflicts:
	in fs/proc/task_mmu.c:
	looks like vma_get_anon_name() want have a name for anonymous
	vma when there is no name used in vma. commit: 586278d78b
	The name show is after any other names, so it maybe covered.
	but anyway, it just a show here.
2016-09-20 15:18:54 +08:00
Linux Build Service Account
b7d007f82e Merge "FROMLIST: security,perf: Allow further restriction of perf_event_open" 2016-09-19 23:27:58 -07:00
Linux Build Service Account
646ce8a905 Merge "cpuset: handle race between CPU hotplug and cpuset_hotplug_work" 2016-09-19 23:27:56 -07:00
Alex Shi
d2d693d1ba Merge remote-tracking branch 'lts/linux-4.4.y' into linux-linaro-lsk-v4.4
Conflicts:
	set ARM64_WORKAROUND_CAVIUM_27456 to 12 in
	arch/arm64/include/asm/cpufeature.h
	and add asm/memory.h in arch/arm64/kernel/entry.S
2016-09-20 10:17:00 +08:00
Oleg Nesterov
f964b3b368 uprobes: Fix the memcg accounting
commit 6c4687cc17a788a6dd8de3e27dbeabb7cbd3e066 upstream.

__replace_page() wronlgy calls mem_cgroup_cancel_charge() in "success" path,
it should only do this if page_check_address() fails.

This means that every enable/disable leads to unbalanced mem_cgroup_uncharge()
from put_page(old_page), it is trivial to underflow the page_counter->count
and trigger OOM.

Reported-and-tested-by: Brenden Blanco <bblanco@plumgrid.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Fixes: 00501b531c ("mm: memcontrol: rewrite charge API")
Link: http://lkml.kernel.org/r/20160817153629.GB29724@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-15 08:27:53 +02:00
John Stultz
4eca11dbd2 timekeeping: Avoid taking lock in NMI path with CONFIG_DEBUG_TIMEKEEPING
commit 27727df240c7cc84f2ba6047c6f18d5addfd25ef upstream.

When I added some extra sanity checking in timekeeping_get_ns() under
CONFIG_DEBUG_TIMEKEEPING, I missed that the NMI safe __ktime_get_fast_ns()
method was using timekeeping_get_ns().

Thus the locking added to the debug checks broke the NMI-safety of
__ktime_get_fast_ns().

This patch open-codes the timekeeping_get_ns() logic for
__ktime_get_fast_ns(), so can avoid any deadlocks in NMI.

Fixes: 4ca22c2648 "timekeeping: Add warnings when overflows or underflows are observed"
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/1471993702-29148-2-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-15 08:27:52 +02:00
John Stultz
42ef9015e0 timekeeping: Cap array access in timekeeping_debug
commit a4f8f6667f099036c88f231dcad4cf233652c824 upstream.

It was reported that hibernation could fail on the 2nd attempt, where the
system hangs at hibernate() -> syscore_resume() -> i8237A_resume() ->
claim_dma_lock(), because the lock has already been taken.

However there is actually no other process would like to grab this lock on
that problematic platform.

Further investigation showed that the problem is triggered by setting
/sys/power/pm_trace to 1 before the 1st hibernation.

Since once pm_trace is enabled, the rtc becomes unmeaningful after suspend,
and meanwhile some BIOSes would like to adjust the 'invalid' RTC (e.g, smaller
than 1970) to the release date of that motherboard during POST stage, thus
after resumed, it may seem that the system had a significant long sleep time
which is a completely meaningless value.

Then in timekeeping_resume -> tk_debug_account_sleep_time, if the bit31 of the
sleep time happened to be set to 1, fls() returns 32 and we add 1 to
sleep_time_bin[32], which causes an out of bounds array access and therefor
memory being overwritten.

As depicted by System.map:
0xffffffff81c9d080 b sleep_time_bin
0xffffffff81c9d100 B dma_spin_lock
the dma_spin_lock.val is set to 1, which caused this problem.

This patch adds a sanity check in tk_debug_account_sleep_time()
to ensure we don't index past the sleep_time_bin array.

[jstultz: Problem diagnosed and original patch by Chen Yu, I've solved the
 issue slightly differently, but borrowed his excelent explanation of the
 issue here.]

Fixes: 5c83545f24 "power: Add option to log time spent in suspend"
Reported-by: Janek Kozicki <cosurgi@gmail.com>
Reported-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Cc: linux-pm@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Xunlei Pang <xpang@redhat.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Zhang Rui <rui.zhang@intel.com>
Link: http://lkml.kernel.org/r/1471993702-29148-3-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-15 08:27:52 +02:00
Balbir Singh
db8c7fff99 cgroup: reduce read locked section of cgroup_threadgroup_rwsem during fork
commit 568ac888215c7fb2fabe8ea739b00ec3c1f5d440 upstream.

cgroup_threadgroup_rwsem is acquired in read mode during process exit
and fork.  It is also grabbed in write mode during
__cgroups_proc_write().  I've recently run into a scenario with lots
of memory pressure and OOM and I am beginning to see

systemd

 __switch_to+0x1f8/0x350
 __schedule+0x30c/0x990
 schedule+0x48/0xc0
 percpu_down_write+0x114/0x170
 __cgroup_procs_write.isra.12+0xb8/0x3c0
 cgroup_file_write+0x74/0x1a0
 kernfs_fop_write+0x188/0x200
 __vfs_write+0x6c/0xe0
 vfs_write+0xc0/0x230
 SyS_write+0x6c/0x110
 system_call+0x38/0xb4

This thread is waiting on the reader of cgroup_threadgroup_rwsem to
exit.  The reader itself is under memory pressure and has gone into
reclaim after fork. There are times the reader also ends up waiting on
oom_lock as well.

 __switch_to+0x1f8/0x350
 __schedule+0x30c/0x990
 schedule+0x48/0xc0
 jbd2_log_wait_commit+0xd4/0x180
 ext4_evict_inode+0x88/0x5c0
 evict+0xf8/0x2a0
 dispose_list+0x50/0x80
 prune_icache_sb+0x6c/0x90
 super_cache_scan+0x190/0x210
 shrink_slab.part.15+0x22c/0x4c0
 shrink_zone+0x288/0x3c0
 do_try_to_free_pages+0x1dc/0x590
 try_to_free_pages+0xdc/0x260
 __alloc_pages_nodemask+0x72c/0xc90
 alloc_pages_current+0xb4/0x1a0
 page_table_alloc+0xc0/0x170
 __pte_alloc+0x58/0x1f0
 copy_page_range+0x4ec/0x950
 copy_process.isra.5+0x15a0/0x1870
 _do_fork+0xa8/0x4b0
 ppc_clone+0x8/0xc

In the meanwhile, all processes exiting/forking are blocked almost
stalling the system.

This patch moves the threadgroup_change_begin from before
cgroup_fork() to just before cgroup_canfork().  There is no nee to
worry about threadgroup changes till the task is actually added to the
threadgroup.  This avoids having to call reclaim with
cgroup_threadgroup_rwsem held.

tj: Subject and description edits.

Signed-off-by: Balbir Singh <bsingharora@gmail.com>
Acked-by: Zefan Li <lizefan@huawei.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-15 08:27:51 +02:00
Tyler Hicks
ad7c1399b7 kernel: Add noaudit variant of ns_capable()
commit 98f368e9e2630a3ce3e80fb10fb2e02038cf9578 upstream.

When checking the current cred for a capability in a specific user
namespace, it isn't always desirable to have the LSMs audit the check.
This patch adds a noaudit variant of ns_capable() for when those
situations arise.

The common logic between ns_capable() and the new ns_capable_noaudit()
is moved into a single, shared function to keep duplicated code to a
minimum and ease maintainability.

Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-15 08:27:50 +02:00
Seth Forshee
4666aa74a3 cred: Reject inodes with invalid ids in set_create_file_as()
[ Upstream commit 5f65e5ca286126a60f62c8421b77c2018a482b8a ]

Using INVALID_[UG]ID for the LSM file creation context doesn't
make sense, so return an error if the inode passed to
set_create_file_as() has an invalid id.

Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-15 08:27:49 +02:00
Vitaly Kuznetsov
a2350f3d82 clocksource: Allow unregistering the watchdog
[ Upstream commit bbf66d897adf2bb0c310db96c97e8db6369f39e1 ]

Hyper-V vmbus module registers TSC page clocksource when loaded. This is
the clocksource with the highest rating and thus it becomes the watchdog
making unloading of the vmbus module impossible.
Separate clocksource_select_watchdog() from clocksource_enqueue_watchdog()
and use it on clocksource register/rating change/unregister.

After all, lobotomized monkeys may need some love too.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Link: http://lkml.kernel.org/r/1453483913-25672-1-git-send-email-vkuznets@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-15 08:27:47 +02:00
John Stultz
1db396648c ntp: Fix ADJ_SETOFFSET being used w/ ADJ_NANO
[ Upstream commit dd4e17ab704269bce71402285f5e8b9ac24b1eff ]

Recently, in commit 37cf4dc3370f I forgot to check if the timeval being passed
was actually a timespec (as is signaled with ADJ_NANO).

This resulted in that patch breaking ADJ_SETOFFSET users who set
ADJ_NANO, by rejecting valid timespecs that were compared with
valid timeval ranges.

This patch addresses this by checking for the ADJ_NANO flag and
using the timepsec check instead in that case.

Reported-by: Harald Hoyer <harald@redhat.com>
Reported-by: Kay Sievers <kay@vrfy.org>
Fixes: 37cf4dc3370f "time: Verify time values in adjtimex ADJ_SETOFFSET to avoid overflow"
Signed-off-by: John Stultz <john.stultz@linaro.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: David Herrmann <dh.herrmann@gmail.com>
Link: http://lkml.kernel.org/r/1453417415-19110-2-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-15 08:27:47 +02:00