When building on my Debian/mips system, util/util.c fails to build
because commit 1aed2671 (perf kvm: Do
guest-only counting by default) indirectly includes stdio.h before the
feature selection in util.h is done.  This prevents _GNU_SOURCE in
util.h from enabling the declaration of getline(), from now second
inclusion of stdio.h, and the build is broken.

There is another breakage in util/evsel.c caused by include ordering,
but I didn't fully track down the commit that caused it.

The root cause of all this is an inconsistent definition of _GNU_SOURCE,
so I move the definition into the Makefile so that it is passed to all
invocations of the compiler and used uniformly for all system header
files.  All other #define and #undef of _GNU_SOURCE are removed as they
cause conflicts with the definition passed to the compiler.

All the features.h definitions (_LARGEFILE64_SOURCE _FILE_OFFSET_BITS=64
and _GNU_SOURCE) are needed by the python glue code too, so they are
moved to BASIC_CFLAGS, and the misleading comments about BASIC_CFLAGS
are removed.

This gives me a clean build on x86_64 (fc12) and mips (Debian).

Cc: David Daney <david.daney@cavium.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1326836461-11952-1-git-send-email-ddaney.cavm@gmail.comSigned-off-by: NDavid Daney <david.daney@cavium.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

"perf stat ... perf bench mem mem..." is pretty meaningless when using
small block sizes (as the overhead of the invocation of each test run
basically hides the actual test result in the noise). Repeating the
actually interesting function's invocation a number of times allows the
results to become meaningful.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/4F16D767020000780006D738@nat28.tlf.novell.comSigned-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

This simply clones the respective memcpy() implementation.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/4F16D743020000780006D735@nat28.tlf.novell.comSigned-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Intended to be able to support the current selection of the preferred
memcpy() implementation, this patch adds the ability to also measure the
two alternative implementations, again by way of using some
pre-processsor replacement.

While on my Westmere system this proves that the movsb based variant is
worse than the movsq based one (since the ERMS feature isn't there), it
also shows that here for the default as well as small sizes the unrolled
variant outperforms the movsq one.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/4F16D728020000780006D732@nat28.tlf.novell.comSigned-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Since arch/x86/lib/memcpy_64.S implements not only __memcpy, but also
memcpy, without further precautions this function will get chose by the
static linker for resolving all references, and hence the "default"
measurement didn't really measure anything else than the
"x86-64-unrolled" one.

Fix this by renaming (through the pre-processor) the conflicting symbol.

On my Westmere system, the glibc variant turns out to require about 4%
less instructions, but 15% more cycles for the default 1Mb block size
measured.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/4F16D6FD020000780006D72F@nat28.tlf.novell.comSigned-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The new --uid command line option will show only the tasks for a given
user, using the proc interface to figure out the existing tasks.

Kernel work is needed to close races at startup, but this should already
be useful in many use cases.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-bdnspm000gw2l984a2t53o8z@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

For helping with debugging.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-m06n4rp7pwr6dlzwoq89cl69@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The ctype.h include is not needed here and it breaks build on some systems (at
least 64bit Ubuntu 10.04) like below. Just get rid of it.

    CC util/trace-event-info.o
cc1: warnings being treated as errors
util/trace-event-info.c: In function ‘record_file’:
util/trace-event-info.c:192: error: implicit declaration of function ‘pwrite’
util/trace-event-info.c:192: error: nested extern declaration of ‘pwrite’
make: *** [util/trace-event-info.o] Error 1

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1326035430-7621-1-git-send-email-namhyung@gmail.comSigned-off-by: NNamhyung Kim <namhyung@gmail.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Current perf report output is broken if --showcpuutilization is used.
Combination with -n and/or --show-total-period make things worse.
This patch fixes it as follows:

before:
    48.25%    48.25%     0.00%    sleep  [kernel.kallsyms]  [k] trace_hardirqs_off
    34.99%    34.99%     0.00%    sleep  [kernel.kallsyms]  [k] __find_get_block_slow
    15.99%    15.99%     0.00%    sleep  [kernel.kallsyms]  [k] lock_release_holdtime
     0.77%     0.77%     0.00%    sleep  [kernel.kallsyms]  [k] native_write_msr_safe

after:
    48.25%    48.25%     0.00%    sleep  [kernel.kallsyms]  [k] trace_hardirqs_off
    34.99%    34.99%     0.00%    sleep  [kernel.kallsyms]  [k] __find_get_block_slow
    15.99%    15.99%     0.00%    sleep  [kernel.kallsyms]  [k] lock_release_holdtime
     0.77%     0.77%     0.00%    sleep  [kernel.kallsyms]  [k] native_write_msr_safe

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1325957132-10600-8-git-send-email-namhyung@gmail.comSigned-off-by: NNamhyung Kim <namhyung@gmail.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The 'field_sep' variable is not set anywhere. Just remove the
conditional.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1325957132-10600-7-git-send-email-namhyung@gmail.comSigned-off-by: NNamhyung Kim <namhyung@gmail.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The annotate command doesn't take non-option arguments.

In fact, it can take last argument as a symbol filter though, but that's
a special case and, IMHO, it should be discouraged in favor of the -s
option.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1325957132-10600-6-git-send-email-namhyung@gmail.comSigned-off-by: NNamhyung Kim <namhyung@gmail.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The 'str' should be freed when sort_dimension__add() failed too.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1325957132-10600-5-git-send-email-namhyung@gmail.comSigned-off-by: NNamhyung Kim <namhyung@gmail.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The setup_cpunode_map() calls opendir() but misses corresponding
closedir(). Add them.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1325957132-10600-4-git-send-email-namhyung@gmail.comSigned-off-by: NNamhyung Kim <namhyung@gmail.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

When a user tries to open so many events, perf_event_open syscall may
fail with EMFILE. Provide advise for that case.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1325957132-10600-3-git-send-email-namhyung@gmail.comSigned-off-by: NNamhyung Kim <namhyung@gmail.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The '-v' option is usually defined via OPT_INCR not _INTEGER.  Follow
the trend :).

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1325957132-10600-2-git-send-email-namhyung@gmail.comSigned-off-by: NNamhyung Kim <namhyung@gmail.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The get_script_path() calls opendir() but misses corresponding
closedir()'s. Add them.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1325957132-10600-1-git-send-email-namhyung@gmail.comSigned-off-by: NNamhyung Kim <namhyung@gmail.com>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Merge branch 'tip/perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core

Merge branch 'tip/perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core

The stack tracer uses the call ftrace_set_early_filter() function
to allow the stack tracer to pick its own functions on boot.
But this function is not defined if dynamic ftrace is not set.
This causes a compiler error when stack tracer is enabled and
dynamic ftrace is not.
Reported-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

Merge branch 'tip/x86/core-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/core

In ELF64, the sh_flags field is 64-bits wide.  recordmcount was
erroneously treating it as a 32-bit wide field.  For little endian
objects this works because the flags of interest (SHF_EXECINSTR)
reside in the lower 32 bits of the word, and you get the same result
with either a 32-bit or 64-bit read.  Big endian objects on the
other hand do not work at all with this error.

The fix:  Correctly treat sh_flags as 64-bits wide in elf64 objects.

The symptom I observed was that my
__start_mcount_loc..__stop_mcount_loc was empty even though ftrace
function tracing was enabled.

Link: http://lkml.kernel.org/r/1324345362-12230-1-git-send-email-ddaney.cavm@gmail.com

Cc: stable@kernel.org # 3.0+
Signed-off-by: NDavid Daney <david.daney@cavium.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

Fixes:
|make: *** No rule to make target `../../include/linux/const.h', needed by `builtin-annotate.o'.  Stop.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1324128938-17553-1-git-send-email-sebastian@breakpoint.ccSigned-off-by: NSebastian Andrzej Siewior <sebastian@breakpoint.cc>
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

To restrict a counter to either host or guest mode this patch introduces
two new event modifiers: G and H.

With G the counter is configured in guest-only mode and with H in
host-only mode.

Cc: Gleb Natapov <gleb@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>
Link: http://lkml.kernel.org/n/tip-or5aj3rghy9ngyg882z6kln9@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Make use of exclude_guest and exlude_host in perf-kvm to do only
guest-only counting by default.

Cc: Gleb Natapov <gleb@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>
[ committer note: Moved perf_{guest,host} & event_attr_init to util.c ]
[                 so as not to drag more stuff to the python binding]
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

It will be recalculated at __hists__output_resort, to take into account
filters possibly applied by the TUI, etc.

Since we do the percent math only for those entries that will appear on
the TUI instead of for _all_ the entries at decay time, updating it for
each sample makes the entries seem to decay faster when using the
navigation keys (since the screen will be refreshed), as we're not
coalescing the entries that are being batched to be merged at next
resort/decay time, but considering their periods.

Bug introduced in 743eb868.
Reported-by: NIngo Molnar <mingo@elte.hu>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-k0d0rq9a8nqtkqohov8cir72@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Stop using this python/OOP convention, doesn't really helps. Will do
more from time to time till we get it cleaned up in all of /perf.
Suggested-by: NThomas Gleixner <tglx@linutronix.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-me4dyj6s5snh7jr8wb9gzt82@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Nowadays we do it per evsel, not per session (that may have multiple
evsels), so rename it to avoid confusion.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-azsgomr5h4dmaudoogw48w49@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  fix CAN MAINTAINERS SCM tree type
  mwifiex: fix crash during simultaneous scan and connect
  b43: fix regression in PIO case
  ath9k: Fix kernel panic in AR2427 in AP mode
  CAN MAINTAINERS update
  net: fsl: fec: fix build for mx23-only kernel
  sch_qfq: fix overflow in qfq_update_start()
  Revert "Bluetooth: Increase HCI reset timeout in hci_dev_do_close"

bitmap size sanity checks should be done *before* allocating ->s_root;
there their cleanup on failure would be correct.  As it is, we do iput()
on root inode, but leak the root dentry...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NJosh Boyer <jwboyer@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This is the temporary simple fix for 3.2, we need more changes in this
area.

1. do_signal_stop() assumes that the running untraced thread in the
   stopped thread group is not possible. This was our goal but it is
   not yet achieved: a stopped-but-resumed tracee can clone the running
   thread which can initiate another group-stop.

   Remove WARN_ON_ONCE(!current->ptrace).

2. A new thread always starts with ->jobctl = 0. If it is auto-attached
   and this group is stopped, __ptrace_unlink() sets JOBCTL_STOP_PENDING
   but JOBCTL_STOP_SIGMASK part is zero, this triggers WANR_ON(!signr)
   in do_jobctl_trap() if another debugger attaches.

   Change __ptrace_unlink() to set the artificial SIGSTOP for report.

   Alternatively we could change ptrace_init_task() to copy signr from
   current, but this means we can copy it for no reason and hide the
   possible similar problems.
Acked-by: NTejun Heo <tj@kernel.org>
Cc: <stable@kernel.org>		[3.1]
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Test-case:

	int main(void)
	{
		int pid, status;

		pid = fork();
		if (!pid) {
			for (;;) {
				if (!fork())
					return 0;
				if (waitpid(-1, &status, 0) < 0) {
					printf("ERR!! wait: %m\n");
					return 0;
				}
			}
		}

		assert(ptrace(PTRACE_ATTACH, pid, 0,0) == 0);
		assert(waitpid(-1, NULL, 0) == pid);

		assert(ptrace(PTRACE_SETOPTIONS, pid, 0,
					PTRACE_O_TRACEFORK) == 0);

		do {
			ptrace(PTRACE_CONT, pid, 0, 0);
			pid = waitpid(-1, NULL, 0);
		} while (pid > 0);

		return 1;
	}

It fails because ->real_parent sees its child in EXIT_DEAD state
while the tracer is going to change the state back to EXIT_ZOMBIE
in wait_task_zombie().

The offending commit is 823b018e which moved the EXIT_DEAD check,
but in fact we should not blame it. The original code was not
correct as well because it didn't take ptrace_reparented() into
account and because we can't really trust ->ptrace.

This patch adds the additional check to close this particular
race but it doesn't solve the whole problem. We simply can't
rely on ->ptrace in this case, it can be cleared if the tracer
is multithreaded by the exiting ->parent.

I think we should kill EXIT_DEAD altogether, we should always
remove the soon-to-be-reaped child from ->children or at least
we should never do the DEAD->ZOMBIE transition. But this is too
complex for 3.2.
Reported-and-tested-by: NDenys Vlasenko <vda.linux@googlemail.com>
Tested-by: NLukasz Michalik <lmi@ift.uni.wroc.pl>
Acked-by: NTejun Heo <tj@kernel.org>
Cc: <stable@kernel.org>		[3.0+]
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

* git://git.samba.org/sfrench/cifs-2.6:
  [CIFS] default ntlmv2 for cifs mount delayed to 3.3
  cifs: fix bad buffer length check in coalesce_t2

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless into for-davem

This reverts commit 93b2ec01.

The call to "schedule_work()" in rtc_initialize_alarm() happens too
early, and can cause oopses at bootup

Neil Brown explains why we do it:

  "If you set an alarm in the future, then shutdown and boot again after
   that time, then you will end up with a timer_queue node which is in
   the past.

   When this happens the queue gets stuck.  That entry-in-the-past won't
   get removed until and interrupt happens and an interrupt won't happen
   because the RTC only triggers an interrupt when the alarm is "now".

   So you'll find that e.g.  "hwclock" will always tell you that
   'select' timed out.

   So we force the interrupt work to happen at the start just in case."

and has a patch that convert it to do things in-process rather than with
the worker thread, but right now it's too late to play around with this,
so we just revert the patch that caused problems for now.
Reported-by: NSander Eikelenboom <linux@eikelenboom.it>
Requested-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Requested-by: NJohn Stultz <john.stultz@linaro.org>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Turned out the ntlmv2 (default security authentication)
upgrade was harder to test than expected, and we ran
out of time to test against Apple and a few other servers
that we wanted to.  Delay upgrade of default security
from ntlm to ntlmv2 (on mount) to 3.3.  Still works
fine to specify it explicitly via "sec=ntlmv2" so this
should be fine.
Acked-by: NJeff Layton <jlayton@samba.org>
Signed-off-by: NSteve French <smfrench@gmail.com>

The current check looks to see if the RFC1002 length is larger than
CIFSMaxBufSize, and fails if it is. The buffer is actually larger than
that by MAX_CIFS_HDR_SIZE.

This bug has been around for a long time, but the fact that we used to
cap the clients MaxBufferSize at the same level as the server tended
to paper over it. Commit c974befa changed that however and caused this
bug to bite in more cases.
Reported-and-Tested-by: NKonstantinos Skarlatos <k.skarlatos@gmail.com>
Tested-by: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

This reverts commit c0afabd3.

It causes failures on Toshiba laptops - instead of disabling the alarm,
it actually seems to enable it on the affected laptops, resulting in
(for example) the laptop powering on automatically five minutes after
shutdown.

There's a patch for it that appears to work for at least some people,
but it's too late to play around with this, so revert for now and try
again in the next merge window.

See for example

	http://bugs.debian.org/652869

Reported-and-bisected-by: Andreas Friedrich <afrie@gmx.net> (Toshiba Tecra)
Reported-by: Antonio-M. Corbi Bellot <antonio.corbi@ua.es> (Toshiba Portege R500)
Reported-by: Marco Santos <marco.santos@waynext.com> (Toshiba Portege Z830)
Reported-by: Christophe Vu-Brugier <cvubrugier@yahoo.fr>  (Toshiba Portege R830)
Cc: Jonathan Nieder <jrnieder@gmail.com>
Requested-by: NJohn Stultz <john.stultz@linaro.org>
Cc: stable@kernel.org  # for the versions that applied this
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

vfork parent uninterruptibly and unkillably waits for its child to
exec/exit. This wait is of unbounded length. Ignore such waits
in the hung_task detector.
Signed-off-by: NMandeep Singh Baines <msb@chromium.org>
Reported-by: NSasha Levin <levinsasha928@gmail.com>
LKML-Reference: <1325344394.28904.43.camel@lappy>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: John Kacur <jkacur@redhat.com>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>