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264269 commits

Author SHA1 Message Date
Thomas Gleixner
908a328372 sched: Fix idle_cpu()
On -rt we observed hackbench waking all 400 tasks to a single cpu.
This is because of select_idle_sibling()'s interaction with the new
ipi based wakeup scheme.

The existing idle_cpu() test only checks to see if the current task on
that cpu is the idle task, it does not take already queued tasks into
account, nor does it take queued to be woken tasks into account.

If the remote wakeup IPIs come hard enough, there won't be time to
schedule away from the idle task, and would thus keep thinking the cpu
was in fact idle, regardless of the fact that there were already
several hundred tasks runnable.

We couldn't reproduce on mainline, but there's no reason it couldn't
happen.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-3o30p18b2paswpc9ohy2gltp@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-04 12:44:07 +02:00
Peter Zijlstra
f0f1d32f93 llist: Remove cpu_relax() usage in cmpxchg loops
Initial benchmarks show they're a net loss:

 $ for i in /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor ; do echo performance > $i; done
 $ echo 4096 32000 64 128 > /proc/sys/kernel/sem
 $ ./sembench -t 2048 -w 1900 -o 0

Pre:

 run time 30 seconds 778936 worker burns per second
 run time 30 seconds 912190 worker burns per second
 run time 30 seconds 817506 worker burns per second
 run time 30 seconds 830870 worker burns per second
 run time 30 seconds 845056 worker burns per second

Post:

 run time 30 seconds 905920 worker burns per second
 run time 30 seconds 849046 worker burns per second
 run time 30 seconds 886286 worker burns per second
 run time 30 seconds 822320 worker burns per second
 run time 30 seconds 900283 worker burns per second

So about 4% faster. (!)

cpu_relax() stalls the pipeline, therefore, when used in a tight loop
it has the following benefits:

 - allows SMT siblings to have a go;
 - reduces pressure on the CPU interconnect.

However, cmpxchg loops are unfair and thus have unbounded completion
time, therefore we should avoid getting in such heavily contended
situations where the above benefits make any difference.

A typical cmpxchg loop should not go round more than a handfull of
times at worst, therefore adding extra delays just slows things down.

Since the llist primitives are new, there aren't any bad users yet,
and we should avoid growing them. Heavily contended sites should
generally be better off using the ticket locks for serialization since
they provide bounded completion times (fifo-fair over the cpus).

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1315836358.26517.43.camel@twins
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-04 12:44:03 +02:00
Peter Zijlstra
fa14ff4acc sched: Convert to struct llist
Use the generic llist primitives.

We had a private lockless list implementation in the scheduler in the wake-list
code, now that we have a generic llist implementation that provides all required
operations, switch to it.

This patch is not expected to change any behavior.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1315836353.26517.42.camel@twins
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-04 12:43:58 +02:00
Peter Zijlstra
924f8f5af3 llist: Add llist_next()
So we don't have to expose the struct list_node member.

Cc: Huang Ying <ying.huang@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1315836348.26517.41.camel@twins
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-04 12:43:53 +02:00
Huang Ying
38aaf8090d irq_work: Use llist in the struct irq_work logic
Use llist in irq_work instead of the lock-less linked list
implementation in irq_work to avoid the code duplication.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1315461646-1379-6-git-send-email-ying.huang@intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-04 12:43:49 +02:00
Huang Ying
781f7fd916 llist: Return whether list is empty before adding in llist_add()
Extend the llist_add*() functions to return a success indicator, this
allows us in the scheduler code to send an IPI if the queue was empty.

( There's no effect on existing users, because the list_add_xxx() functions
  are inline, thus this will be optimized out by the compiler if not used
  by callers. )

Signed-off-by: Huang Ying <ying.huang@intel.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1315461646-1379-5-git-send-email-ying.huang@intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-04 12:43:44 +02:00
Huang Ying
a3127336b7 llist: Move cpu_relax() to after the cmpxchg()
If in llist_add()/etc. functions the first cmpxchg() call succeeds, it is
not necessary to use cpu_relax() before the cmpxchg(). So cpu_relax() in
a busy loop involving cmpxchg() should go after cmpxchg() instead of before
that.

This patch fixes this for all involved llist functions.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1315461646-1379-4-git-send-email-ying.huang@intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-04 12:43:39 +02:00
Ingo Molnar
2c30245c65 llist: Remove the platform-dependent NMI checks
Remove the nmi() checks spread around the code. in_nmi() is not available
on every architecture and it's a pretty obscure and ugly check in any case.

Cc: Huang Ying <ying.huang@intel.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1315461646-1379-3-git-send-email-ying.huang@intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-04 12:43:11 +02:00
Huang Ying
1230db8e15 llist: Make some llist functions inline
Because llist code will be used in performance critical scheduler
code path, make llist_add() and llist_del_all() inline to avoid
function calling overhead and related 'glue' overhead.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1315461646-1379-2-git-send-email-ying.huang@intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-04 11:30:53 +02:00
Ingo Molnar
22f92bacbe Merge branch 'linus' into sched/core
Merge reason: pick up the latest fixes.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-10-04 11:09:08 +02:00
Linus Torvalds
0f86267b79 Merge branch 'hwmon-for-linus' of git://github.com/groeck/linux
* 'hwmon-for-linus' of git://github.com/groeck/linux:
  hwmon: (coretemp) Avoid leaving around dangling pointer
  hwmon: (coretemp) Fixup platform device ID change
2011-10-03 12:54:56 -07:00
Linus Torvalds
0d617928f5 Merge git://github.com/davem330/ide
* git://github.com/davem330/ide:
  ide-disk: Fix request requeuing
2011-10-03 12:53:43 -07:00
Linus Torvalds
7fd21be75d Merge branch 'btrfs-3.0' of git://github.com/chrismason/linux
* 'btrfs-3.0' of git://github.com/chrismason/linux:
  Btrfs: force a page fault if we have a shorty copy on a page boundary
2011-10-03 12:17:44 -07:00
Borislav Petkov
2c8fc86760 ide-disk: Fix request requeuing
Simon Kirby reported that on his RAID setup with idedisk underneath
the box OOMs after a couple of days of runtime. Running with
CONFIG_DEBUG_KMEMLEAK pointed to idedisk_prep_fn() which unconditionally
allocates an ide_cmd struct. However, ide_requeue_and_plug() can be
called more than once per request, either from the request issue or the
IRQ handler path and do blk_peek_request() ends up in idedisk_prep_fn()
repeatedly, allocating a struct ide_cmd everytime and "forgetting" the
previous pointer.

Make sure the code reuses the old allocated chunk.

Reported-and-tested-by: Simon Kirby <sim@hostway.ca>
Cc: <stable@kernel.org> [ 39.x, 3.0.x ]
Link: http://marc.info/?l=linux-kernel&m=131667641517919
Link: http://lkml.kernel.org/r/20110922072643.GA27232@hostway.ca
Signed-off-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-03 14:28:18 -04:00
Linus Torvalds
9b13776977 Merge branch 'for-linus' of git://git.infradead.org/users/sameo/mfd-2.6
* 'for-linus' of git://git.infradead.org/users/sameo/mfd-2.6:
  mfd: Fix generic irq chip ack function name for jz4740-adc
2011-10-02 19:23:44 -07:00
Linus Torvalds
4edf5886bb Merge branch 'for-linus' of git://github.com/tiwai/sound
* 'for-linus' of git://github.com/tiwai/sound:
  ALSA: hda - Fix a regression of the position-buffer check
2011-10-02 19:22:44 -07:00
Linus Torvalds
2e51818107 Merge branch 'perf-urgent-for-linus' of git://tesla.tglx.de/git/linux-2.6-tip
* 'perf-urgent-for-linus' of git://tesla.tglx.de/git/linux-2.6-tip:
  perf tools: Fix raw sample reading
2011-10-01 17:46:13 -07:00
Linus Torvalds
f72a209a3e Merge branches 'irq-urgent-for-linus', 'x86-urgent-for-linus' and 'sched-urgent-for-linus' of git://tesla.tglx.de/git/linux-2.6-tip
* 'irq-urgent-for-linus' of git://tesla.tglx.de/git/linux-2.6-tip:
  irq: Fix check for already initialized irq_domain in irq_domain_add
  irq: Add declaration of irq_domain_simple_ops to irqdomain.h

* 'x86-urgent-for-linus' of git://tesla.tglx.de/git/linux-2.6-tip:
  x86/rtc: Don't recursively acquire rtc_lock

* 'sched-urgent-for-linus' of git://tesla.tglx.de/git/linux-2.6-tip:
  posix-cpu-timers: Cure SMP wobbles
  sched: Fix up wchan borkage
  sched/rt: Migrate equal priority tasks to available CPUs
2011-10-01 08:37:25 -07:00
Josef Bacik
b6316429af Btrfs: force a page fault if we have a shorty copy on a page boundary
A user reported a problem where ceph was getting into 100% cpu usage while doing
some writing.  It turns out it's because we were doing a short write on a not
uptodate page, which means we'd fall back at one page at a time and fault the
page in.  The problem is our position is on the page boundary, so our fault in
logic wasn't actually reading the page, so we'd just spin forever or until the
page got read in by somebody else.  This will force a readpage if we end up
doing a short copy.  Alexandre could reproduce this easily with ceph and reports
it fixes his problem.  I also wrote a reproducer that no longer hangs my box
with this patch.  Thanks,

Reported-and-tested-by: Alexandre Oliva <aoliva@redhat.com>
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-09-30 15:23:54 -04:00
Ingo Molnar
9d3ec7a0c4 Merge branch 'perf/urgent' of git://github.com/acmel/linux into perf/urgent 2011-09-30 20:08:56 +02:00
Peter Zijlstra
d670ec1317 posix-cpu-timers: Cure SMP wobbles
David reported:

  Attached below is a watered-down version of rt/tst-cpuclock2.c from
  GLIBC.  Just build it with "gcc -o test test.c -lpthread -lrt" or
  similar.

  Run it several times, and you will see cases where the main thread
  will measure a process clock difference before and after the nanosleep
  which is smaller than the cpu-burner thread's individual thread clock
  difference.  This doesn't make any sense since the cpu-burner thread
  is part of the top-level process's thread group.

  I've reproduced this on both x86-64 and sparc64 (using both 32-bit and
  64-bit binaries).

  For example:

  [davem@boricha build-x86_64-linux]$ ./test
  process: before(0.001221967) after(0.498624371) diff(497402404)
  thread:  before(0.000081692) after(0.498316431) diff(498234739)
  self:    before(0.001223521) after(0.001240219) diff(16698)
  [davem@boricha build-x86_64-linux]$ 

  The diff of 'process' should always be >= the diff of 'thread'.

  I make sure to wrap the 'thread' clock measurements the most tightly
  around the nanosleep() call, and that the 'process' clock measurements
  are the outer-most ones.

  ---
  #include <unistd.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <time.h>
  #include <fcntl.h>
  #include <string.h>
  #include <errno.h>
  #include <pthread.h>

  static pthread_barrier_t barrier;

  static void *chew_cpu(void *arg)
  {
	  pthread_barrier_wait(&barrier);
	  while (1)
		  __asm__ __volatile__("" : : : "memory");
	  return NULL;
  }

  int main(void)
  {
	  clockid_t process_clock, my_thread_clock, th_clock;
	  struct timespec process_before, process_after;
	  struct timespec me_before, me_after;
	  struct timespec th_before, th_after;
	  struct timespec sleeptime;
	  unsigned long diff;
	  pthread_t th;
	  int err;

	  err = clock_getcpuclockid(0, &process_clock);
	  if (err)
		  return 1;

	  err = pthread_getcpuclockid(pthread_self(), &my_thread_clock);
	  if (err)
		  return 1;

	  pthread_barrier_init(&barrier, NULL, 2);
	  err = pthread_create(&th, NULL, chew_cpu, NULL);
	  if (err)
		  return 1;

	  err = pthread_getcpuclockid(th, &th_clock);
	  if (err)
		  return 1;

	  pthread_barrier_wait(&barrier);

	  err = clock_gettime(process_clock, &process_before);
	  if (err)
		  return 1;

	  err = clock_gettime(my_thread_clock, &me_before);
	  if (err)
		  return 1;

	  err = clock_gettime(th_clock, &th_before);
	  if (err)
		  return 1;

	  sleeptime.tv_sec = 0;
	  sleeptime.tv_nsec = 500000000;
	  nanosleep(&sleeptime, NULL);

	  err = clock_gettime(th_clock, &th_after);
	  if (err)
		  return 1;

	  err = clock_gettime(my_thread_clock, &me_after);
	  if (err)
		  return 1;

	  err = clock_gettime(process_clock, &process_after);
	  if (err)
		  return 1;

	  diff = process_after.tv_nsec - process_before.tv_nsec;
	  printf("process: before(%lu.%.9lu) after(%lu.%.9lu) diff(%lu)\n",
		 process_before.tv_sec, process_before.tv_nsec,
		 process_after.tv_sec, process_after.tv_nsec, diff);
	  diff = th_after.tv_nsec - th_before.tv_nsec;
	  printf("thread:  before(%lu.%.9lu) after(%lu.%.9lu) diff(%lu)\n",
		 th_before.tv_sec, th_before.tv_nsec,
		 th_after.tv_sec, th_after.tv_nsec, diff);
	  diff = me_after.tv_nsec - me_before.tv_nsec;
	  printf("self:    before(%lu.%.9lu) after(%lu.%.9lu) diff(%lu)\n",
		 me_before.tv_sec, me_before.tv_nsec,
		 me_after.tv_sec, me_after.tv_nsec, diff);

	  return 0;
  }

This is due to us using p->se.sum_exec_runtime in
thread_group_cputime() where we iterate the thread group and sum all
data. This does not take time since the last schedule operation (tick
or otherwise) into account. We can cure this by using
task_sched_runtime() at the cost of having to take locks.

This also means we can (and must) do away with
thread_group_sched_runtime() since the modified thread_group_cputime()
is now more accurate and would deadlock when called from
thread_group_sched_runtime().

Aside of that it makes the function safe on 32 bit systems. The old
code added t->se.sum_exec_runtime unprotected. sum_exec_runtime is a
64bit value and could be changed on another cpu at the same time.

Reported-by: David Miller <davem@davemloft.net>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: stable@kernel.org
Link: http://lkml.kernel.org/r/1314874459.7945.22.camel@twins
Tested-by: David Miller <davem@davemloft.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-09-30 14:07:06 +02:00
Takashi Iwai
798cb7e897 ALSA: hda - Fix a regression of the position-buffer check
The commit a810364a04
    ALSA: hda - Handle -1 as invalid position, too
caused a regression on some machines that require the position-buffer
instead of LPIB, e.g. resulting in noises with mic recording with
PulseAudio.

This patch fixes the detection by delaying the test at the timing as
same as 3.0, i.e. doing the position check only when requested in
azx_position_ok().

Reported-and-tested-by: Rocko Requin <rockorequin@hotmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2011-09-30 08:57:15 +02:00
Ram Pai
47ea91b405 Resource: fix wrong resource window calculation
__find_resource() incorrectly returns a resource window which overlaps
an existing allocated window.  This happens when the parent's
resource-window spans 0x00000000 to 0xffffffff and is entirely allocated
to all its children resource-windows.

__find_resource() looks for gaps in resource allocation among the
children resource windows.  When it encounters the last child window it
blindly tries the range next to one allocated to the last child.  Since
the last child's window ends at 0xffffffff the calculation overflows,
leading the algorithm to believe that any window in the range 0x0000000
to 0xfffffff is available for allocation.  This leads to a conflicting
window allocation.

Michal Ludvig reported this issue seen on his platform.  The following
patch fixes the problem and has been verified by Michal.  I believe this
bug has been there for ages.  It got exposed by git commit 2bbc694227
("PCI : ability to relocate assigned pci-resources")

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Tested-by: Michal Ludvig <mludvig@logix.net.nz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-29 20:04:34 -07:00
Linus Torvalds
92bb062fe3 Merge branch 'for-linus' of git://github.com/NewDreamNetwork/ceph-client
* 'for-linus' of git://github.com/NewDreamNetwork/ceph-client:
  libceph: fix pg_temp mapping update
  libceph: fix pg_temp mapping calculation
  libceph: fix linger request requeuing
  libceph: fix parse options memory leak
  libceph: initialize ack_stamp to avoid unnecessary connection reset
2011-09-29 19:58:58 -07:00
Linus Torvalds
7409b7132c Merge branch 'v4l_for_linus' of git://linuxtv.org/mchehab/for_linus
* 'v4l_for_linus' of git://linuxtv.org/mchehab/for_linus:
  [media] omap3isp: Fix build error in ispccdc.c
  [media] uvcvideo: Fix crash when linking entities
  [media] v4l: Make sure we hold a reference to the v4l2_device before using it
  [media] v4l: Fix use-after-free case in v4l2_device_release
  [media] uvcvideo: Set alternate setting 0 on resume if the bus has been reset
  [media] OMAP_VOUT: Fix build break caused by update_mode removal in DSS2
2011-09-29 19:29:45 -07:00
Linus Torvalds
0ecdb12a7a Merge branch 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6
* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6:
  [S390] cio: fix cio_tpi ignoring adapter interrupts
  [S390] gmap: always up mmap_sem properly
  [S390] Do not clobber personality flags on exec
2011-09-29 19:28:26 -07:00
Linus Torvalds
5fe858b5b7 Merge git://github.com/davem330/sparc
* git://github.com/davem330/sparc:
  sparc64: Force the execute bit in OpenFirmware's translation entries.
  sparc: Make '-p' boot option meaningful again.
  sparc, exec: remove redundant addr_limit assignment
  sparc64: Future proof Niagara cpu detection.
2011-09-29 19:24:33 -07:00
Linus Torvalds
8e8e500fca Merge branch 'drm-intel-fixes' of git://people.freedesktop.org/~keithp/linux
* 'drm-intel-fixes' of git://people.freedesktop.org/~keithp/linux:
  drm/i915: FBC off for ironlake and older, otherwise on by default
  drm/i915: Enable SDVO hotplug interrupts for HDMI and DVI
  drm/i915: Enable dither whenever display bpc < frame buffer bpc
2011-09-29 19:23:30 -07:00
Benjamin Herrenschmidt
16fa42affd powerpc: Fix device-tree matching for Apple U4 bridge
Apple Quad G5 has some oddity in it's device-tree which causes the new
generic matching code to fail to relate nodes for PCI-E devices below U4
with their respective struct pci_dev.  This breaks graphics on those
machines among others.

This fixes it using a quirk which copies the node pointer from the host
bridge for the root complex, which makes the generic code work for the
children afterward.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-29 19:22:40 -07:00
wangyanqing
b0f84374b6 bootup: move 'usermodehelper_enable()' a little earlier
Commit d5767c5353 ("bootup: move 'usermodehelper_enable()' to the end
of do_basic_setup()") moved 'usermodehelper_enable()' to end of
do_basic_setup() to after the initcalls.  But then I get failed to let
uvesafb work on my computer, and lose the splash boot.

So maybe we could start usermodehelper_enable a little early to make
some task work that need eary init with the help of user mode.

[ I would *really* prefer that initcalls not call into user space - even
  the real 'init' hasn't been execve'd yet, after all! But for uvesafb
  it really does look like we don't have much choice.

  I considered doing this when we mount the root filesystem, but
  depending on config options that is in multiple places.  We could do
  the usermode helper enable as a rootfs_initcall()..

  So I'm just using wang yanqing's trivial patch.  It's not wonderful,
  but it's simple and should work.  We should revisit this some day,
  though.      - Linus ]

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-29 19:21:01 -07:00
Jiri Olsa
8e303f20f4 perf tools: Fix raw sample reading
Wrong pointer is being passed for raw data sanity checking, when parsing
sample event.

This ends up with invalid event and perf record being stuck in
__perf_session__process_events function during processing build IDs
(process_buildids function).

Following command hangs up in my setup:
	./perf record -e raw_syscalls:sys_enter ls

The fix is to use proper pointer to the raw data instead of the 'u'
union.

Reviewed-by: David Ahern <dsahern@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1317308709-9474-2-git-send-email-jolsa@redhat.com
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2011-09-29 16:29:53 -03:00
David S. Miller
f4142cba4e sparc64: Force the execute bit in OpenFirmware's translation entries.
In the OF 'translations' property, the template TTEs in the mappings
never specify the executable bit.  This is the case even though some
of these mappings are for OF's code segment.

Therefore, we need to force the execute bit on in every mapping.

This problem can only really trigger on Niagara/sun4v machines and the
history behind this is a little complicated.

Previous to sun4v, the sun4u TTE entries lacked a hardware execute
permission bit.  So OF didn't have to ever worry about setting
anything to handle executable pages.  Any valid TTE loaded into the
I-TLB would be respected by the chip.

But sun4v Niagara chips have a real hardware enforced executable bit
in their TTEs.  So it has to be set or else the I-TLB throws an
instruction access exception with type code 6 (protection violation).

We've been extremely fortunate to not get bitten by this in the past.

The best I can tell is that the OF's mappings for it's executable code
were mapped using permanent locked mappings on sun4v in the past.
Therefore, the fact that we didn't have the exec bit set in the OF
translations we would use did not matter in practice.

Thanks to Greg Onufer for helping me track this down.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-09-29 12:18:59 -07:00
Linus Torvalds
d5767c5353 bootup: move 'usermodehelper_enable()' to the end of do_basic_setup()
Doing it just before starting to call into cpu_idle() made a sick kind
of sense only because the original bug we fixed (see commit
288d5abec8: "Boot up with usermodehelper disabled") was about problems
with some scheduler data structures not being initialized, and they had
better be initialized at that point.

But it really didn't make any other conceptual sense, and doing it after
the initial "schedule()" call for the idle thread actually opened up a
race: what if the main initialization thread did everything without
needing to sleep, and got all the way into user land too? Without
actually having scheduled back to the idle thread?

Now, in normal circumstances that doesn't ever happen, but it looks like
Richard Cochran triggered exactly that on his ARM IXP4xx machines:

  "I have some ARM IXP4xx based machines that use the two on chip MAC
   ports (aka NPEs).  The NPE needs a firmware in order to function.
   Ever since the following commit [that 288d5abec8 one], it is no
   longer possible to bring up the interfaces during the init scripts."

with a call trace showing an ioctl coming from user space. Richard says:

  "The init is busybox, and the startup script does mount, syslogd, and
   then ifup, so that all can go by quickly."

The fix is to move the usermodehelper_enable() into the main 'init'
thread, and just put it after we've done all our initcalls.  By then,
everything really should be up, but we've obviously not actually started
the user-mode portion of init yet.

Reported-and-tested-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-28 10:23:44 -07:00
Sage Weil
8adc8b3d78 libceph: fix pg_temp mapping update
The incremental map updates have a record for each pg_temp mapping that is
to be add/updated (len > 0) or removed (len == 0).  The old code was
written as if the updates were a complete enumeration; that was just wrong.
Update the code to remove 0-length entries and drop the rbtree traversal.

This avoids misdirected (and hung) requests that manifest as server
errors like

[WRN] client4104 10.0.1.219:0/275025290 misdirected client4104.1:129 0.1 to osd0 not [1,0] in e11/11

Signed-off-by: Sage Weil <sage@newdream.net>
2011-09-28 10:13:35 -07:00
Sage Weil
782e182e91 libceph: fix pg_temp mapping calculation
We need to apply the modulo pg_num calculation before looking up a pgid in
the pg_temp mapping rbtree.  This fixes pg_temp mappings, and fixes
(some) misdirected requests that result in messages like

[WRN] client4104 10.0.1.219:0/275025290 misdirected client4104.1:129 0.1 to osd0 not [1,0] in e11/11

on the server and stall make the client block without getting a reply (at
least until the pg_temp mapping goes way, but that can take a long long
time).

Reorder calc_pg_raw() a bit to make more sense.

Signed-off-by: Sage Weil <sage@newdream.net>
2011-09-28 10:13:31 -07:00
Linus Torvalds
2ef7b45a59 Merge git://github.com/davem330/net
* git://github.com/davem330/net:
  ipv6-multicast: Fix memory leak in IPv6 multicast.
  ipv6: check return value for dst_alloc
  net: check return value for dst_alloc
  ipv6-multicast: Fix memory leak in input path.
  bnx2x: add missing break in bnx2x_dcbnl_get_cap
  bnx2x: fix WOL by enablement PME in config space
  bnx2x: fix hw attention handling
  net: fix a typo in Documentation/networking/scaling.txt
  ath9k: Fix a dma warning/memory leak
  rtlwifi: rtl8192cu: Fix unitialized struct
  iwlagn: fix dangling scan request
  batman-adv: do_bcast has to be true for broadcast packets only
  cfg80211: Fix validation of AKM suites
  iwlegacy: do not use interruptible waits
  iwlegacy: fix command queue timeout
  ath9k_hw: Fix Rx DMA stuck for AR9003 chips
2011-09-28 08:39:05 -07:00
Linus Torvalds
07117e3054 Merge git://bedivere.hansenpartnership.com/git/scsi-rc-fixes-2.6
* git://bedivere.hansenpartnership.com/git/scsi-rc-fixes-2.6:
  [SCSI] 3w-9xxx: fix iommu_iova leak
  [SCSI] cxgb3i: convert cdev->l2opt to use rcu to prevent NULL dereference
  [SCSI] scsi: qla4xxx needs libiscsi.o
  [SCSI] libsas: fix failure to revalidate domain for anything but the first expander child.
  [SCSI] aacraid: reset should disable MSI interrupt
2011-09-28 08:23:39 -07:00
Guenter Roeck
20ecb499f6 hwmon: (coretemp) Avoid leaving around dangling pointer
Storing the struct temp_data pointer allocated from create_core_data()
when returning an error has the potential of leaving around a pointer
to freed memory. Reset it to NULL for error returns.

Reported-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
2011-09-28 08:19:21 -07:00
Jean Delvare
0eb9782ad9 hwmon: (coretemp) Fixup platform device ID change
With recent change "hwmon: (coretemp) don't use kernel assigned CPU
number as platform device ID", the microcode check is now running on
random CPU. Fix that by checking the microcode before creating the
platform device rather than at probe time.

Also avoid calling TO_PHYS_ID(cpu) twice in the same function, it's
expensive.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Guenter Roeck <guenter.roeck@ericsson.com>
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
2011-09-28 08:19:20 -07:00
Linus Torvalds
c54a06d45a Merge branch 'for-linus' of git://git.kernel.dk/linux-block
* 'for-linus' of git://git.kernel.dk/linux-block:
  block: Free queue resources at blk_release_queue()
2011-09-28 08:03:00 -07:00
Linus Torvalds
e689ec8057 Merge branch 'writeback-for-linus' of git://github.com/fengguang/linux
* 'writeback-for-linus' of git://github.com/fengguang/linux:
  writeback: show raw dirtied_when in trace writeback_single_inode
2011-09-28 08:01:05 -07:00
Hannes Reinecke
777eb1bf15 block: Free queue resources at blk_release_queue()
A kernel crash is observed when a mounted ext3/ext4 filesystem is
physically removed. The problem is that blk_cleanup_queue() frees up
some resources eg by calling elevator_exit(), which are not checked for
in normal operation. So we should rather move these calls to the
destructor function blk_release_queue() as at that point all remaining
references are gone. However, in doing so we have to ensure that any
externally supplied queue_lock is disconnected as the driver might free
up the lock after the call of blk_cleanup_queue(),

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2011-09-28 08:07:01 -06:00
David S. Miller
b582ad8e96 Merge branch 'for-davem' of git://git.infradead.org/users/linville/wireless 2011-09-27 22:42:30 -04:00
Linus Torvalds
a102a9ece5 Linux 3.1-rc8 2011-09-27 15:48:34 -07:00
Linus Torvalds
058e0676ba Merge branch 'for-linus' of git://github.com/tiwai/sound
* 'for-linus' of git://github.com/tiwai/sound:
  ASoC: ssm2602: Re-enable oscillator after suspend
  ALSA: usb-audio: Check for possible chip NULL pointer before clearing probing flag
  ALSA: hda/realtek - Don't detect LO jack when identical with HP
  ALSA: hda/realtek - Avoid bogus HP-pin assignment
  ALSA: HDA: No power nids on 92HD93
  ASoC: omap-mcbsp: Do not attempt to change DAI sysclk if stream is active
2011-09-27 15:46:21 -07:00
Linus Torvalds
57119327df Merge branch 'pm-fixes' of git://github.com/rjwysocki/linux-pm
* 'pm-fixes' of git://github.com/rjwysocki/linux-pm:
  PM / Clocks: Do not acquire a mutex under a spinlock
2011-09-27 15:41:32 -07:00
John W. Linville
a8acfd82eb Merge branch 'master' of git://git.infradead.org/users/linville/wireless into for-davem 2011-09-27 15:47:33 -04:00
Ben Greear
67928c4041 ipv6-multicast: Fix memory leak in IPv6 multicast.
If reg_vif_xmit cannot find a routing entry, be sure to
free the skb before returning the error.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-09-27 15:34:00 -04:00
Madalin Bucur
fbe5818690 ipv6: check return value for dst_alloc
return value of dst_alloc must be checked before use

Signed-off-by: Madalin Bucur <madalin.bucur@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-09-27 15:32:06 -04:00
Madalin Bucur
d4cae56219 net: check return value for dst_alloc
return value of dst_alloc must be checked before use

Signed-off-by: Madalin Bucur <madalin.bucur@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-09-27 15:32:06 -04:00