Commit Graph

506942 Commits

Author SHA1 Message Date
Thomas Huth
a6b7e459ff KVM: s390: Make the simple ipte mutex specific to a VM instead of global
The ipte-locking should be done for each VM seperately, not globally.
This way we avoid possible congestions when the simple ipte-lock is used
and multiple VMs are running.

Suggested-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2014-10-28 13:08:59 +01:00
Takashi Iwai
317168d0c7 ALSA: pcm: Zero-clear reserved fields of PCM status ioctl in compat mode
In compat mode, we copy each field of snd_pcm_status struct but don't
touch the reserved fields, and this leaves uninitialized values
there.  Meanwhile the native ioctl does zero-clear the whole
structure, so we should follow the same rule in compat mode, too.

Reported-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2014-10-28 12:45:53 +01:00
Mauro Carvalho Chehab
d6d41ba1cb Merge remote-tracking branch 'linus/master' into patchwork
Merge back media fixes applied upstream.

* linus/master: (457 commits)
  Linux 3.18-rc2
  ARM: dts: imx28-evk: Let i2c0 run at 100kHz
  ARM: i.MX6: Fix "emi" clock name typo
  overlayfs: embed middle into overlay_readdir_data
  overlayfs: embed root into overlay_readdir_data
  overlayfs: make ovl_cache_entry->name an array instead of pointer
  overlayfs: don't hold ->i_mutex over opening the real directory
  arm64: Fix memblock current_limit with 64K pages and 48-bit VA
  sparc64: Implement __get_user_pages_fast().
  sparc64: Fix register corruption in top-most kernel stack frame during boot.
  arm64: ASLR: Don't randomise text when randomise_va_space == 0
  [media] s5p-jpeg: Avoid -Wuninitialized warning in s5p_jpeg_parse_hdr
  [media] s5p-fimc: Only build suspend/resume for PM
  [media] s5p-jpeg: Only build suspend/resume for PM
  [media] Remove references to non-existent PLAT_S5P symbol
  MIPS: SEAD3: Fix I2C device registration.
  [media] videobuf-dma-contig: set vm_pgoff to be zero to pass the sanity check in vm_iomap_memory()
  [media] tw68: remove bogus I2C_ALGOBIT dependency
  kvm: vfio: fix unregister kvm_device_ops of vfio
  KVM: x86: Wrong assertion on paging_tmpl.h
  ...
2014-10-28 09:22:17 -02:00
Minfei Huang
96e70f8328 x86/mm: Avoid overlap the fixmap area on i386
It is a problem when configuring high memory off where the
vmalloc reserve area could end up overlapping the early_ioremap
fixmap area on i386.

The ordering of the VMALLOC_RESERVE space is:

 FIXADDR_TOP
                       fixed_addresses
 FIXADDR_START
                       early_ioremap fixed addresses
 FIXADDR_BOOT_START
                       Persistent kmap area
 PKMAP_BASE
 VMALLOC_END
                       Vmalloc area
 VMALLOC_START
 high_memory

The available address we can use is lower than
FIXADDR_BOOT_START. So we will set the kmap boundary below the
FIXADDR_BOOT_START, if we configure high memory.

If we configure high memory, the vmalloc reserve area should
end up to PKMAP_BASE, otherwise should end up to
FIXADDR_BOOT_START.

Signed-off-by: Minfei Huang <mnfhuang@gmail.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/6B680A9E-6CE9-4C96-934B-CB01DCB58278@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 12:21:48 +01:00
Maciej W. Rozycki
60e684f0d6 x86/irq: Fix XT-PIC-XT-PIC in /proc/interrupts
Fix duplicate XT-PIC seen in /proc/interrupts on x86 systems
that make  use of 8259A Programmable Interrupt Controllers.
Specifically convert  output like this:

           CPU0
  0:      76573    XT-PIC-XT-PIC    timer
  1:         11    XT-PIC-XT-PIC    i8042
  2:          0    XT-PIC-XT-PIC    cascade
  4:          8    XT-PIC-XT-PIC    serial
  6:          3    XT-PIC-XT-PIC    floppy
  7:          0    XT-PIC-XT-PIC    parport0
  8:          1    XT-PIC-XT-PIC    rtc0
 10:        448    XT-PIC-XT-PIC    fddi0
 12:         23    XT-PIC-XT-PIC    eth0
 14:       2464    XT-PIC-XT-PIC    ide0
NMI:          0   Non-maskable interrupts
ERR:          0

to one like this:

           CPU0
  0:     122033    XT-PIC  timer
  1:         11    XT-PIC  i8042
  2:          0    XT-PIC  cascade
  4:          8    XT-PIC  serial
  6:          3    XT-PIC  floppy
  7:          0    XT-PIC  parport0
  8:          1    XT-PIC  rtc0
 10:        145    XT-PIC  fddi0
 12:         31    XT-PIC  eth0
 14:       2245    XT-PIC  ide0
NMI:          0   Non-maskable interrupts
ERR:          0

that is one like we used to have from ~2.2 till it was changed
sometime.

The rationale is there is no value in this duplicate
information, it  merely clutters output and looks ugly.  We only
have one handler for  8259A interrupts so there is no need to
give it a name separate from the  name already given to
irq_chip.

We could define meaningful names for handlers based on bits in
the ELCR  register on systems that have it or the value of the
LTIM bit we use in  ICW1 otherwise (hardcoded to 0 though with
MCA support gone), to tell  edge-triggered and level-triggered
inputs apart.  While that information  does not affect 8259A
interrupt handlers it could help people determine  which lines
are shareable and which are not.  That is material for a
separate change though.

Any tools that parse /proc/interrupts are supposed not to be
affected  since it was many years we used the format this change
converts back to.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/alpine.LFD.2.11.1410260147190.21390@eddie.linux-mips.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 12:01:08 +01:00
Axel Lin
b2a9a3b818 ASoC: es8328-i2c: Fix i2c_device_id name field in es8328_id
The convention for i2c_device_id name does not need to have company prefix.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2014-10-28 10:48:03 +00:00
Nicholas Mc Guire
a1a5831d29 x86/asm: Fix typo in arch/x86/kernel/asm_offset_64.c
Drop double entry for pt_regs_bx.

This seems to be a typo - resulting in a double entry in the
generated include/generated/asm-offsets.h, which is not necessary.

Build-tested and booted on x86 64 box to make sure it was not
doing any strange magic.... after all it was in the kernel in
this form for almost 10 years.

Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20141027172805.GA19760@opentech.at
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:24:17 +01:00
Andy Lutomirski
1c0c1b93df x86_64/vdso: Clean up vgetcpu init and merge the vdso initcalls
Now vdso/vma.c has a single initcall and no references to
"vsyscall".

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/945c463e2804fedd8b08d63a040cbe85d55195aa.1411494540.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:22:14 +01:00
Andy Lutomirski
61a492fb17 x86_64/vdso: Remove jiffies from the vvar page
I think that the jiffies vvar was once used for the vgetcpu
cache. That code is long gone, so let's just make jiffies be a
normal variable.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/fcfee6f8749af14d96373a9e2656354ad0b95499.1411494540.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:22:13 +01:00
Andy Lutomirski
287e013108 x86/vdso: Make the PER_CPU segment 32 bits
IMO users ought not to be able to use 16-bit segments without
using modify_ldt.  Fortunately, it's impossible to break
espfix64 by loading the PER_CPU segment into SS because it's
PER_CPU is marked read-only and SS cannot contain an RO segment,
but marking PER_CPU as 32-bit is less fragile.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/179f490d659307873eefd09206bebd417e2ab5ad.1411494540.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:22:12 +01:00
Andy Lutomirski
9c0080ef93 x86/vdso: Make the PER_CPU segment start out accessed
The first userspace attempt to read or write the PER_CPU segment
will write the accessed bit to the GDT.  This is visible to
userspace using the LAR instruction, and it also pointlessly
dirties a cache line.

Set the segment's accessed bit at boot to prevent userspace
access to segments from having side effects.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/ac63814ca4c637a08ec2fd0360d67ca67560a9ee.1411494540.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:22:11 +01:00
Andy Lutomirski
258801563b x86/vdso: Change the PER_CPU segment to use struct desc_struct
This makes it easier to see what's going on.  It produces
exactly the same segment descriptor as the old code.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/d492f7b55136cbc60f016adae79160707b2e03b7.1411494540.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:22:10 +01:00
Andy Lutomirski
d4f829dd90 x86_64/vdso: Move getcpu code from vsyscall_64.c to vdso/vma.c
This is pure cut-and-paste.  At this point, vsyscall_64.c
contains only code needed for vsyscall emulation, but some of
the comments and function names are still confused.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/a244daf7d3cbe71afc08ad09fdfe1866ca1f1978.1411494540.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:22:09 +01:00
Andy Lutomirski
b93590901a x86_64/vsyscall: Move all of the gate_area code to vsyscall_64.c
This code exists for the sole purpose of making the vsyscall
page look sort of like real userspace memory.  Move it so that
it lives with the rest of the vsyscall code.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/a7ee266773671a05f00b7175ca65a0dd812d2e4b.1411494540.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:22:08 +01:00
David Cohen
d90c338189 pinctrl: baytrail: show output gpio state correctly on Intel Baytrail
Even if a gpio pin is set to output, we still need to set INPUT_EN
functionality (by clearing INPUT_EN bit) to be able to read the pin's
level.

E.g. without this change, we'll always read low level state from sysfs.

Cc: <stable@vger.kernel.org> # v3.14+
Cc: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: David Cohen <david.a.cohen@linux.intel.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-10-28 11:16:26 +01:00
Andy Lutomirski
c4a7bba29b sched/x86: Add a comment clarifying LDT context switching
The code is correct, but only for a rather subtle reason.  This
confused me for quite a while when I read switch_mm, so clarify
the code to avoid confusing other people, too.

TBH, I wouldn't be surprised if this code was only correct by
accident.

[ I wouldn't normally send a comment-only patch, but it took me a long
  time to first figure out wtf was going on here, and then to figure
  out why this wasn't exploitable by malicious code, and then to
  figure out why this oddity had no user-visible effect at all.  Let's
  spare future readers the same confusion. ]

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/36275c99801a87d8dcf0502a41cf4e2ad81aae46.1412623954.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:11:57 +01:00
Andy Lutomirski
2c7577a758 sched/x86_64: Don't save flags on context switch
Now that the kernel always runs with clean flags (in particular,
NT is clear), there is no need to save and restore flags on
every context switch.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Sebastian Lackner <sebastian@fds-team.de>
Cc: Anish Bhatt <anish@chelsio.com>
Cc: Chuck Ebbert <cebbert.lkml@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jan Beulich <jbeulich@suse.com>
Link: http://lkml.kernel.org/r/bf6fb790787eb95b922157838f52712c25dda157.1412187233.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:11:30 +01:00
Steven Noonan
5631b8fba6 compiler/gcc4+: Remove inaccurate comment about 'asm goto' miscompiles
The bug referenced by the comment in this commit was not
completely fixed in GCC 4.8.2, as I mentioned in a thread back
in February:

   https://lkml.org/lkml/2014/2/12/797

The conclusion at that time was to make the quirk unconditional
until the bug could be found and fixed in GCC. Unfortunately,
when I submitted the patch (commit a9f18034) I left a comment
in that claimed the bug was fixed in GCC 4.8.2+.

This comment is inaccurate, and should be removed.

Signed-off-by: Steven Noonan <steven@uplinklabs.net>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Jakub Jelinek <jakub@redhat.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1414274982-14040-1-git-send-email-steven@uplinklabs.net
Cc: Ingo Molnar <mingo@kernel.org>
2014-10-28 11:03:40 +01:00
Peter Zijlstra
3427445afd sched: Exclude cond_resched() from nested sleep test
cond_resched() is a preemption point, not strictly a blocking
primitive, so exclude it from the ->state test.

In particular, preemption preserves task_struct::state.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: tglx@linutronix.de
Cc: ilya.dryomov@inktank.com
Cc: umgwanakikbuti@gmail.com
Cc: oleg@redhat.com
Cc: Alex Elder <alex.elder@linaro.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Axel Lin <axel.lin@ingics.com>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20140924082242.656559952@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:56:57 +01:00
Peter Zijlstra
8eb23b9f35 sched: Debug nested sleeps
Validate we call might_sleep() with TASK_RUNNING, which catches places
where we nest blocking primitives, eg. mutex usage in a wait loop.

Since all blocking is arranged through task_struct::state, nesting
this will cause the inner primitive to set TASK_RUNNING and the outer
will thus not block.

Another observed problem is calling a blocking function from
schedule()->sched_submit_work()->blk_schedule_flush_plug() which will
then destroy the task state for the actual __schedule() call that
comes after it.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: tglx@linutronix.de
Cc: ilya.dryomov@inktank.com
Cc: umgwanakikbuti@gmail.com
Cc: oleg@redhat.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140924082242.591637616@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:56:52 +01:00
Peter Zijlstra
26cabd3125 sched, net: Clean up sk_wait_event() vs. might_sleep()
WARNING: CPU: 1 PID: 1744 at kernel/sched/core.c:7104 __might_sleep+0x58/0x90()
do not call blocking ops when !TASK_RUNNING; state=1 set at [<ffffffff81070e10>] prepare_to_wait+0x50 /0xa0

 [<ffffffff8105bc38>] __might_sleep+0x58/0x90
 [<ffffffff8148c671>] lock_sock_nested+0x31/0xb0
 [<ffffffff81498aaa>] sk_stream_wait_memory+0x18a/0x2d0

Which is a false positive because sk_wait_event() will already have
TASK_RUNNING at that point if it would've gone through
schedule_timeout().

So annotate with sched_annotate_sleep(); which goes away on !DEBUG builds.

Reported-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140924082242.524407432@infradead.org
Cc: David S. Miller <davem@davemloft.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: netdev@vger.kernel.org
Cc: tglx@linutronix.de
Cc: ilya.dryomov@inktank.com
Cc: umgwanakikbuti@gmail.com
Cc: oleg@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:56:37 +01:00
Peter Zijlstra
3c9b2c3d64 sched, modules: Fix nested sleep in add_unformed_module()
This is a genuine bug in add_unformed_module(), we cannot use blocking
primitives inside a wait loop.

So rewrite the wait_event_interruptible() usage to use the fresh
wait_woken() stuff.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: tglx@linutronix.de
Cc: ilya.dryomov@inktank.com
Cc: umgwanakikbuti@gmail.com
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: oleg@redhat.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: http://lkml.kernel.org/r/20140924082242.458562904@infradead.org
[ So this is probably complex to backport and the race wasn't reported AFAIK,
  so not marked for -stable. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:56:30 +01:00
Peter Zijlstra
7d4d26966e sched, smp: Correctly deal with nested sleeps
smp_hotplug_thread::{setup,unpark} functions can sleep too, so be
consistent and do the same for all callbacks.

 __might_sleep+0x74/0x80
 kmem_cache_alloc_trace+0x4e/0x1c0
 perf_event_alloc+0x55/0x450
 perf_event_create_kernel_counter+0x2f/0x100
 watchdog_nmi_enable+0x8d/0x160
 watchdog_enable+0x45/0x90
 smpboot_thread_fn+0xec/0x2b0
 kthread+0xe4/0x100
 ret_from_fork+0x7c/0xb0

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: tglx@linutronix.de
Cc: ilya.dryomov@inktank.com
Cc: umgwanakikbuti@gmail.com
Cc: oleg@redhat.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140924082242.392279328@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:56:24 +01:00
Peter Zijlstra
97d9e28d1a sched, tty: Deal with nested sleeps
n_tty_{read,write} are wait loops with sleeps in. Wait loops rely on
task_struct::state and sleeps do too, since that's the only means of
actually sleeping. Therefore the nested sleeps destroy the wait loop
state.

Fix this by using the new woken_wake_function and wait_woken() stuff,
which registers wakeups in wait and thereby allows shrinking the
task_state::state changes to the actual sleep part.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: tglx@linutronix.de
Cc: ilya.dryomov@inktank.com
Cc: umgwanakikbuti@gmail.com
Cc: oleg@redhat.com
Link: http://lkml.kernel.org/r/20140924082242.323011233@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:56:10 +01:00
Peter Zijlstra
e23738a730 sched, inotify: Deal with nested sleeps
inotify_read is a wait loop with sleeps in. Wait loops rely on
task_struct::state and sleeps do too, since that's the only means of
actually sleeping. Therefore the nested sleeps destroy the wait loop
state and the wait loop breaks the sleep functions that assume
TASK_RUNNING (mutex_lock).

Fix this by using the new woken_wake_function and wait_woken() stuff,
which registers wakeups in wait and thereby allows shrinking the
task_state::state changes to the actual sleep part.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: tglx@linutronix.de
Cc: ilya.dryomov@inktank.com
Cc: umgwanakikbuti@gmail.com
Cc: Robert Love <rlove@rlove.org>
Cc: Eric Paris <eparis@parisplace.org>
Cc: John McCutchan <john@johnmccutchan.com>
Cc: Robert Love <rlove@rlove.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/20140924082242.254858080@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:55:37 +01:00
Peter Zijlstra
1029a2b52c sched, exit: Deal with nested sleeps
do_wait() is a big wait loop, but we set TASK_RUNNING too late; we end
up calling potential sleeps before we reset it.

Not strictly a bug since we're guaranteed to exit the loop and not
call schedule(); put in annotations to quiet might_sleep().

 WARNING: CPU: 0 PID: 1 at ../kernel/sched/core.c:7123 __might_sleep+0x7e/0x90()
 do not call blocking ops when !TASK_RUNNING; state=1 set at [<ffffffff8109a788>] do_wait+0x88/0x270

 Call Trace:
  [<ffffffff81694991>] dump_stack+0x4e/0x7a
  [<ffffffff8109877c>] warn_slowpath_common+0x8c/0xc0
  [<ffffffff8109886c>] warn_slowpath_fmt+0x4c/0x50
  [<ffffffff810bca6e>] __might_sleep+0x7e/0x90
  [<ffffffff811a1c15>] might_fault+0x55/0xb0
  [<ffffffff8109a3fb>] wait_consider_task+0x90b/0xc10
  [<ffffffff8109a804>] do_wait+0x104/0x270
  [<ffffffff8109b837>] SyS_wait4+0x77/0x100
  [<ffffffff8169d692>] system_call_fastpath+0x16/0x1b

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: tglx@linutronix.de
Cc: umgwanakikbuti@gmail.com
Cc: ilya.dryomov@inktank.com
Cc: Alex Elder <alex.elder@linaro.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Axel Lin <axel.lin@ingics.com>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Guillaume Morin <guillaume@morinfr.org>
Cc: Ionut Alexa <ionut.m.alexa@gmail.com>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Michal Schmidt <mschmidt@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20140924082242.186408915@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:55:30 +01:00
Peter Zijlstra
e22b886a8a sched/wait: Add might_sleep() checks
Add more might_sleep() checks, suppose someone put a wait_event() like
thing in a wait loop..

Can't put might_sleep() in ___wait_event() because there's the locked
primitives which call ___wait_event() with locks held.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: tglx@linutronix.de
Cc: ilya.dryomov@inktank.com
Cc: umgwanakikbuti@gmail.com
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140924082242.119255706@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:55:23 +01:00
Peter Zijlstra
61ada528de sched/wait: Provide infrastructure to deal with nested blocking
There are a few places that call blocking primitives from wait loops,
provide infrastructure to support this without the typical
task_struct::state collision.

We record the wakeup in wait_queue_t::flags which leaves
task_struct::state free to be used by others.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: tglx@linutronix.de
Cc: ilya.dryomov@inktank.com
Cc: umgwanakikbuti@gmail.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140924082242.051202318@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:55:15 +01:00
Peter Zijlstra
6f942a1f26 locking/mutex: Don't assume TASK_RUNNING
We're going to make might_sleep() test for TASK_RUNNING, because
blocking without TASK_RUNNING will destroy the task state by setting
it to TASK_RUNNING.

There are a few occasions where its 'valid' to call blocking
primitives (and mutex_lock in particular) and not have TASK_RUNNING,
typically such cases are right before we set TASK_RUNNING anyhow.

Robustify the code by not assuming this; this has the beneficial side
effect of allowing optional code emission for fixing the above
might_sleep() false positives.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: tglx@linutronix.de
Cc: ilya.dryomov@inktank.com
Cc: umgwanakikbuti@gmail.com
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140924082241.988560063@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:55:08 +01:00
Peter Zijlstra
7fb0f1de49 perf/x86: Fix compile warnings for intel_uncore
The uncore drivers require PCI and generate compile time warnings when
!CONFIG_PCI.

Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:51:03 +01:00
Andy Lutomirski
b438b1ab35 perf: Fix typos in sample code in the perf_event.h header
struct perf_event_mmap_page has members called "index" and
"cap_user_rdpmc".  Spell them correctly in the examples.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-api@vger.kernel.org
Link: http://lkml.kernel.org/r/320ba26391a8123cc16e5f02d24d34bd404332fd.1412313343.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:51:02 +01:00
Peter Zijlstra
c719f56092 perf: Fix and clean up initialization of pmu::event_idx
Andy reported that the current state of event_idx is rather confused.
So remove all but the x86_pmu implementation and change the default to
return 0 (the safe option).

Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Cody P Schafer <cody@linux.vnet.ibm.com>
Cc: Cody P Schafer <dev@codyps.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Himangi Saraogi <himangi774@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: sukadev@linux.vnet.ibm.com <sukadev@linux.vnet.ibm.com>
Cc: Thomas Huth <thuth@linux.vnet.ibm.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux390@de.ibm.com
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-s390@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:51:01 +01:00
Peter Zijlstra (Intel)
65d71fe137 perf: Fix bogus kernel printk
Andy spotted the fail in what was intended as a conditional printk level.

Reported-by: Andy Lutomirski <luto@amacapital.net>
Fixes: cc6cd47e73 ("perf/x86: Tone down kernel messages when the PMU check fails in a virtual environment")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20141007124757.GH19379@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:51:01 +01:00
Ulf Hansson
29417fe80a ARM: ux500: Add i2c devices to the VAPE PM domain
The i2c-nomadik driver handle these devices properly from a runtime PM
perspective. Therefore, let's add them into VAPE PM domain for ux500.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-10-28 10:50:46 +01:00
Ulf Hansson
770e2f6bc3 ARM: ux500: Add spi and ssp devices to the VAPE PM domain
The spi-pl022 driver handle these devices properly from a runtime PM
perspective. Therefore, let's add them into VAPE PM domain for ux500.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-10-28 10:50:21 +01:00
Ulf Hansson
067addec0e ARM: ux500: Add sdi devices to the VAPE PM domain
The mmci driver handle these devices properly from a runtime PM
perspective, including register context save/restore. Therefore let's
add them into VAPE PM domain for ux500.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-10-28 10:49:52 +01:00
Ulf Hansson
6c6693599b ARM: ux500: Add DT node for ux500 PM domains
Add a DT node for the ux500 PM domains. Follow the DT semantics of the
generic PM domain.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-10-28 10:49:27 +01:00
Ulf Hansson
c8f4594381 ARM: ux500: Enable Kconfig for the generic PM domain
Since ux500 uses the generic PM domain, let's enable the corresponding
Kconfig as long as CONFIG_PM also is enabled.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-10-28 10:48:52 +01:00
Ulf Hansson
cd931dcfda ARM: ux500: Initial support for PM domains
The ux500 SoC uses the generic PM domain and requires the domains to be
specified through DT.

Currently the genpd callbacks for handling power gating|ungating are
implemented as dummy functions. To be able to enable those to perform
PM domain gating/ungating, each device that resides in the VAPE domain
must be properly handled from a runtime PM perspective.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-10-28 10:48:23 +01:00
Wanpeng Li
f4e9d94a5b sched/deadline: Don't balance during wakeup if wakee is pinned
Use nr_cpus_allowed to bail from select_task_rq() when only one cpu
can be used, and saves some cycles for pinned tasks.

Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1413253360-5318-2-git-send-email-wanpeng.li@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:48:02 +01:00
Wanpeng Li
1d7e974cbf sched/deadline: Don't check SD_BALANCE_FORK
There is no need to do balance during fork since SCHED_DEADLINE
tasks can't fork. This patch avoid the SD_BALANCE_FORK check.

Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1413253360-5318-1-git-send-email-wanpeng.li@linux.intel.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:48:01 +01:00
Juri Lelli
f82f80426f sched/deadline: Ensure that updates to exclusive cpusets don't break AC
How we deal with updates to exclusive cpusets is currently broken.
As an example, suppose we have an exclusive cpuset composed of
two cpus: A[cpu0,cpu1]. We can assign SCHED_DEADLINE task to it
up to the allowed bandwidth. If we want now to modify cpusetA's
cpumask, we have to check that removing a cpu's amount of
bandwidth doesn't break AC guarantees. This thing isn't checked
in the current code.

This patch fixes the problem above, denying an update if the
new cpumask won't have enough bandwidth for SCHED_DEADLINE tasks
that are currently active.

Signed-off-by: Juri Lelli <juri.lelli@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: cgroups@vger.kernel.org
Link: http://lkml.kernel.org/r/5433E6AF.5080105@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:48:00 +01:00
Juri Lelli
7f51412a41 sched/deadline: Fix bandwidth check/update when migrating tasks between exclusive cpusets
Exclusive cpusets are the only way users can restrict SCHED_DEADLINE tasks
affinity (performing what is commonly called clustered scheduling).
Unfortunately, such thing is currently broken for two reasons:

 - No check is performed when the user tries to attach a task to
   an exlusive cpuset (recall that exclusive cpusets have an
   associated maximum allowed bandwidth).

 - Bandwidths of source and destination cpusets are not correctly
   updated after a task is migrated between them.

This patch fixes both things at once, as they are opposite faces
of the same coin.

The check is performed in cpuset_can_attach(), as there aren't any
points of failure after that function. The updated is split in two
halves. We first reserve bandwidth in the destination cpuset, after
we pass the check in cpuset_can_attach(). And we then release
bandwidth from the source cpuset when the task's affinity is
actually changed. Even if there can be time windows when sched_setattr()
may erroneously fail in the source cpuset, we are fine with it, as
we can't perfom an atomic update of both cpusets at once.

Reported-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Reported-by: Vincent Legout <vincent@legout.info>
Signed-off-by: Juri Lelli <juri.lelli@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Dario Faggioli <raistlin@linux.it>
Cc: Michael Trimarchi <michael@amarulasolutions.com>
Cc: Fabio Checconi <fchecconi@gmail.com>
Cc: michael@amarulasolutions.com
Cc: luca.abeni@unitn.it
Cc: Li Zefan <lizefan@huawei.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: cgroups@vger.kernel.org
Link: http://lkml.kernel.org/r/1411118561-26323-3-git-send-email-juri.lelli@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:47:58 +01:00
Ulf Hansson
5dcb10159b dt: bindings: ux500: Add header for PM domains specifiers
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-10-28 10:47:57 +01:00
Wanpeng Li
d9aade7ae1 sched/deadline: Do not try to push tasks if pinned task switches to dl
As Kirill mentioned (https://lkml.org/lkml/2013/1/29/118):

 | If rq has already had 2 or more pushable tasks and we try to add a
 | pinned task then call of push_rt_task will just waste a time.

Just switched pinned task is not able to be pushed. If the rq has had
several dl tasks before they have already been considered as candidates
to be pushed (or pulled). This patch implements the same behavior as rt
class which introduced by commit 1044791755 ("sched/rt: Do not try to
push tasks if pinned task switches to RT").

Suggested-by: Kirill V Tkhai <tkhai@yandex.ru>
Acked-by: Juri Lelli <juri.lelli@arm.com>
Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1413938203-224610-1-git-send-email-wanpeng.li@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:47:57 +01:00
Oleg Nesterov
e2336f6e51 sched: Kill task_preempt_count()
task_preempt_count() is pointless if preemption counter is per-cpu,
currently this is x86 only. It is only valid if the task is not
running, and even in this case the only info it can provide is the
state of PREEMPT_ACTIVE bit.

Change its single caller to check p->on_rq instead, this should be
the same if p->state != TASK_RUNNING, and kill this helper.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Kirill Tkhai <tkhai@yandex.ru>
Cc: Alexander Graf <agraf@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-arch@vger.kernel.org
Link: http://lkml.kernel.org/r/20141008183348.GC17495@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:47:56 +01:00
Oleg Nesterov
dfa50b605c sched: Make finish_task_switch() return 'struct rq *'
Both callers of finish_task_switch() need to recalculate this_rq()
and pass it as an argument, plus __schedule() does this again after
context_switch().

It would be simpler to call this_rq() once in finish_task_switch()
and return the this rq to the callers.

Note: probably "int cpu" in __schedule() should die; it is not used
and both rcu_note_context_switch() and wq_worker_sleeping() do not
really need this argument.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Kirill Tkhai <tkhai@yandex.ru>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20141009193232.GB5408@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:47:55 +01:00
Oleg Nesterov
1a43a14a5b sched: Fix schedule_tail() to disable preemption
finish_task_switch() enables preemption, so post_schedule(rq) can be
called on the wrong (and even dead) CPU. Afaics, nothing really bad
can happen, but in this case we can wrongly clear rq->post_schedule
on that CPU. And this simply looks wrong in any case.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Kirill Tkhai <tkhai@yandex.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20141008193644.GA32055@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:47:54 +01:00
Oleg Nesterov
8f9fbf092c sched: Fix the PREEMPT_ACTIVE check in __trace_sched_switch_state()
task_preempt_count() has nothing to do with the actual preempt counter,
thread_info->saved_preempt_count is only valid right after switch_to().

__trace_sched_switch_state() can use preempt_count(), prev is still the
current task when trace_sched_switch() is called.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
[ Added BUG_ON(). ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20141007195108.GB28002@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:47:53 +01:00
Rik van Riel
9de05d4871 sched/numa: Check all nodes when placing a pseudo-interleaved group
In pseudo-interleaved numa_groups, all tasks try to relocate to
the group's preferred_nid.  When a group is spread across multiple
NUMA nodes, this can lead to tasks swapping their location with
other tasks inside the same group, instead of swapping location with
tasks from other NUMA groups. This can keep NUMA groups from converging.

Examining all nodes, when dealing with a task in a pseudo-interleaved
NUMA group, avoids this problem. Note that only CPUs in nodes that
improve the task or group score are examined, so the loop isn't too
bad.

Tested-by: Vinod Chegu <chegu_vinod@hp.com>
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: "Vinod Chegu" <chegu_vinod@hp.com>
Cc: mgorman@suse.de
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20141009172747.0d97c38c@annuminas.surriel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:47:52 +01:00