Introduce sysfs attribute /sys/power/pm_test allowing one to test the suspend
core code.  Namely, writing one of the strings:

freezer
devices
platform
processors
core

to this file causes the suspend code to work in one of the test modes defined as
follows:

freezer
- test the freezing of processes

devices
- test the freezing of processes and suspending of devices

platform
- test the freezing of processes, suspending of devices and platform global
  control methods(*)

processors
- test the freezing of processes, suspending of devices, platform global
  control methods and the disabling of nonboot CPUs

core
- test the freezing of processes, suspending of devices, platform global
  control methods, the disabling of nonboot CPUs and suspending of
  platform/system devices

(*) These are ACPI global control methods on ACPI systems

Then, if a suspend is started by normal means, the suspend core will perform
its normal operations up to the point indicated by given test level.  Next, it
will wait for 5 seconds and carry out the resume operations needed to transition
the system back to the fully functional state.

Writing "none" to /sys/power/pm_test turns the testing off.

When open for reading, /sys/power/pm_test contains a space-separated list of all
available tests (including "none" that represents the normal functionality) in
which the current test level is indicated by square brackets.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NLen Brown <len.brown@intel.com>

Add PM_RESTORE_PREPARE and PM_POST_RESTORE notifiers to the PM core, to be used
in analogy with the existing PM_HIBERNATION_PREPARE and PM_POST_HIBERNATION
notifiers.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: N"Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: NLen Brown <len.brown@intel.com>

This patch moves the prototypes of count_highmem_pages() and
restore_highmem() to kernel/power/power.h
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Acked-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NLen Brown <len.brown@intel.com>

Move the definitions of hibernation ioctls to a separate header file in
include/linux, which can be exported to the user space.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NLen Brown <len.brown@intel.com>

Three ioctl numbers belonging to the hibernation userland interface,
SNAPSHOT_ATOMIC_SNAPSHOT, SNAPSHOT_AVAIL_SWAP, SNAPSHOT_GET_SWAP_PAGE,
are defined in a wrong way (eg. not portable).  Provide new ioctl numbers for
these ioctls and mark the existing ones as deprecated.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NLen Brown <len.brown@intel.com>

Mark the SNAPSHOT_SET_SWAP_FILE ioctl belonging to the hibernation userland
interface as deprecated.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NLen Brown <len.brown@intel.com>

Modify the hibernation userland interface by adding two new ioctls to it,
SNAPSHOT_PLATFORM_SUPPORT and SNAPSHOT_POWER_OFF, that can be used,
respectively, to switch the hibernation platform support on/off and to make the
kernel transition the system to the hibernation state (eg. ACPI S4) using the
platform (eg. ACPI) driver.

These ioctls are intended to replace the misdesigned SNAPSHOT_PMOPS ioctl,
which from now is regarded as obsolete and will be removed in the future.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NLen Brown <len.brown@intel.com>

Add a new ioctl, SNAPSHOT_GET_IMAGE_SIZE, returning the size of the (just
created) hibernation image, to the hibernation userland interface.

This ioctl is necessary so that the userland utilities using the interface need
not access the hibernation image header, owned by the kernel, in order to obtain
the size of the image.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NLen Brown <len.brown@intel.com>

some printk messages from the audit system can become excessive.  This
patch ratelimits those messages.  It was found that messages, such as
the audit backlog lost printk message could flood the logs to the point
that a machine could take an nmi watchdog hit or otherwise become
unresponsive.
Signed-off-by: NEric Paris <eparis@redhat.com>

Complement va_copy() with va_end().
Signed-off-by: NRichard Knutsson <ricknu-0@student.ltu.se>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>

kernel/audit.c: In function 'audit_log_start':
kernel/audit.c:1133: warning: 'serial' may be used uninitialized in this function

Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>

Disabling audit at runtime by auditctl doesn't mean that we can
stop allocating contexts for new processes; we don't want to miss them
when that sucker is reenabled.

(based on work from Al Viro in the RHEL kernel series)
Signed-off-by: NEric Paris <eparis@redhat.com>

generally clean up audit_receive_msg() don't free random memory if
selinux_sid_to_string fails for some reason.  Move generic auditing
to a helper function
Signed-off-by: NEric Paris <eparis@redhat.com>

Some audit messages (namely configuration changes) are still emitted even if
the audit subsystem has been explicitly disabled.  This patch turns those
messages off as well.
Signed-off-by: NEric Paris <eparis@redhat.com>

execve arguments can be quite large.  There is no limit on the number of
arguments and a 4G limit on the size of an argument.

this patch prints those aruguments in bite sized pieces.  a userspace size
limitation of 8k was discovered so this keeps messages around 7.5k

single arguments larger than 7.5k in length are split into multiple records
and can be identified as aX[Y]=
Signed-off-by: NEric Paris <eparis@redhat.com>

Currently audit drops the audit type when an audit message goes through
printk instead of the audit deamon.  This is a minor annoyance in
that the audit type is no longer part of the message and the information
the audit type conveys needs to be carried in, or derived from the
message data.

The attached patch includes the type number as part of the printk.
Admittedly it isn't the type name that the audit deamon provides but I
think this is better than dropping the type completely.
Signed-pff-by: NJohn Johansen <jjohansen@suse.de>
Signed-off-by: NEric Paris <eparis@redhat.com>

If we fail to get an ab in audit_log_pid_context this may be due to an exclude
rule rather than a memory allocation failure.  If it was due to a memory
allocation failue we would have already paniced and no need to do it again.
Signed-off-by: NEric Paris <eparis@redhat.com>

This patch adds an end of event record type. It will be sent by the kernel as
the last record when a multi-record event is triggered. This will aid realtime
analysis programs since they will now reliably know they have the last record
to complete an event. The audit daemon filters this and will not write it to
disk.

Signed-off-by: Steve Grubb <sgrubb redhat com>
Signed-off-by: NEric Paris <eparis@redhat.com>

In order to correlate audit records to an individual login add a session
id.  This is incremented every time a user logs in and is included in
almost all messages which currently output the auid.  The field is
labeled ses=  or oses=
Signed-off-by: NEric Paris <eparis@redhat.com>

Add uid, loginuid, and comm collection to OBJ_PID records.  This just
gives users a little more information about the task that received a
signal.  pid is rather meaningless after the fact, and even though comm
isn't great we can't collect exe reasonably on this code path for
performance reasons.
Signed-off-by: NEric Paris <eparis@redhat.com>

The syscall exit code will change ERESTART* kernel internal return codes
to EINTR if it does not restart the syscall.  Since we collect the audit
info before that point we should fix those in the audit log as well.
Signed-off-by: NEric Paris <eparis@redhat.com>

Keeping loginuid in audit_context is racy and results in messier
code.  Taken to task_struct, out of the way of ->audit_context
changes.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

all callers pass something->audit_context
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

To allow the implementation of optimized rw-locks in user space, glibc
needs a possibility to select waiters for wakeup depending on a bitset
mask.

This requires two new futex OPs: FUTEX_WAIT_BITS and FUTEX_WAKE_BITS
These OPs are basically the same as FUTEX_WAIT and FUTEX_WAKE plus an
additional argument - a bitset. Further the FUTEX_WAIT_BITS OP is
expecting an absolute timeout value instead of the relative one, which
is used for the FUTEX_WAIT OP.

FUTEX_WAIT_BITS calls into the kernel with a bitset. The bitset is
stored in the futex_q structure, which is used to enqueue the waiter
into the hashed futex waitqueue.

FUTEX_WAKE_BITS also calls into the kernel with a bitset. The wakeup
function logically ANDs the bitset with the bitset stored in each
waiters futex_q structure. If the result is zero (i.e. none of the set
bits in the bitsets is matching), then the waiter is not woken up. If
the result is not zero (i.e. one of the set bits in the bitsets is
matching), then the waiter is woken.

The bitset provided by the caller must be non zero. In case the
provided bitset is zero the kernel returns EINVAL.

Internaly the new OPs are only extensions to the existing FUTEX_WAIT
and FUTEX_WAKE functions. The existing OPs hand a bitset with all bits
set into the futex_wait() and futex_wake() functions.
Signed-off-by: NThomas Gleixner <tgxl@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The WARN_ON() in the fixup return path of futex_lock_pi() can
trigger with false positives.

The following scenario happens:
t1 holds the futex and t2 and t3 are blocked on the kernel side rt_mutex.
t1 releases the futex (and the rt_mutex) and assigned t2 to be the next
owner of the futex.

t2 is interrupted and returns w/o acquiring the rt_mutex, before t1 can
release the rtmutex.

t1 releases the rtmutex and t3 becomes the pending owner of the rtmutex.

t2 notices that it is the designated owner (user space variable) and
fails to acquire the rt_mutex via trylock, because it is not allowed to
steal the rt_mutex from t3. Now it looks at the rt_mutex pending owner (t3)
and assigns the futex and the pi_state to it.

During the fixup t4 steals the rtmutex from t3.

t2 returns from the fixup and the owner of the rt_mutex has changed from
t3 to t4.

There is no need to do another round of fixups from t2. The important
part (t2 is not returning as the user space visible owner) is
done. The further fixups are done, before either t3 or t4 return to
user space.

For the user space it is not relevant which task (t3 or t4) is the real
owner, as long as those are both in the kernel, which is guaranteed by
the serialization of the hash bucket lock. Both tasks (which ever returns
first to userspace - t4 because it locked the rt_mutex or t3 due to a signal)
are going through the lock_futex_pi() return path where the ownership is
fixed before the return to user space.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

To allow better diagnosis of tick-sched related, especially NOHZ
related problems, we need to know when the last wakeup via an irq
happened and when the CPU left the idle state.

Add two fields (idle_waketime, idle_exittime) to the tick_sched
structure and add them to the timer_list output.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

xtime_cache needs to be updated whenever xtime and or wall_to_monotic
are changed. Otherwise users of xtime_cache might see a stale (and in
the case of timezone changes utterly wrong) value until the next
update happens.

Fixup the obvious places, which miss this update.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NJohn Stultz <johnstul@us.ibm.com>
Tested-by: NDhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

this patch:

 commit 37bb6cb4
 Author: Peter Zijlstra <a.p.zijlstra@chello.nl>
 Date:   Fri Jan 25 21:08:32 2008 +0100

     hrtimer: unlock hrtimer_wakeup

Broke hrtimer_init_sleeper() users. It forgot to fix up the futex
caller of this function to detect the failed queueing and messed up
the do_nanosleep() caller in that it could leak a TASK_INTERRUPTIBLE
state.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The recent UDP patch exposed this bug in the audit code.  It
was calling pskb_expand_head without increasing skb->truesize.
The caller of pskb_expand_head needs to do so because that function
is designed to be called in places where truesize is already fixed
and therefore it doesn't update its value.

Because the audit system is using it in a place where the truesize
has not yet been fixed, it needs to update its value manually.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Acked-by: NJames Morris <jmorris@namei.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It may be used by the modules nfs.ko and sunrpc.ko
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
[ Made it a regular export rather than GPL-only  - Linus ]
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

i was debugging early crashes and wondered where all the printks
went. The reason: ignore_loglevel_setup() was not called yet ...
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This removes the extra struct task_struct *p parameter in inc_nr_running
and dec_nr_running functions.

Signed-off by: Jerry Stralko <gerb.stralko@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Michel Dänzr has bisected an interactivity problem with
plus-reniced tasks back to this commit:

 810e95cc is first bad commit
 commit 810e95cc
 Author: Peter Zijlstra <a.p.zijlstra@chello.nl>
 Date:   Mon Oct 15 17:00:14 2007 +0200

 sched: another wakeup_granularity fix

      unit mis-match: wakeup_gran was used against a vruntime

fix this by assymetrically scaling the vtime of positive reniced
tasks.
Bisected-by: NMichel Dänzer <michel@tungstengraphics.com>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The reason why we are getting better wakeup latencies for
!FAIR_USER_SCHED is because of this snippet of code in place_entity():

	if (!initial) {
		/* sleeps upto a single latency don't count. */
		if (sched_feat(NEW_FAIR_SLEEPERS) && entity_is_task(se))
						     ^^^^^^^^^^^^^^^^^^
			vruntime -= sysctl_sched_latency;

		/* ensure we never gain time by being placed backwards. */
		vruntime = max_vruntime(se->vruntime, vruntime);
	}

NEW_FAIR_SLEEPERS feature gives credit for sleeping only to tasks and
not group-level entities. With the patch attached, I could see that
wakeup latencies with FAIR_USER_SCHED are restored to the same level as
!FAIR_USER_SCHED.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

We don't want the meaning of guest userspace changing under our feet.
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

these bugs are harder to find than they seem, a stackdump helps.

make it dependent on CONFIG_DEBUG_SHIRQ so that people can turn it off
if it annoys them.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

During the work on the x86 32 and 64 bit backtrace code I found it useful
to have a simple test module to test a process and irq context backtrace.
Since the existing backtrace code was buggy, I figure it might be useful
to have such a test module in the kernel so that maybe we can even
detect such bugs earlier..

[ mingo@elte.hu: build fix ]
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Enable CONFIG_EMBEDDED to select CONFIG_EARLY_PRINTK on 64-bit as well.

saves ~2K:

   text    data     bss     dec     hex filename
   7290283 3672091 1907848 12870222         c4624e vmlinux.before
   7288373 3671795 1907848 12868016         c459b0 vmlinux.after
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Here is a quick and naive smoke test for kprobes. This is intended to
just verify if some unrelated change broke the *probes subsystem. It is
self contained, architecture agnostic and isn't of any great use by itself.

This needs to be built in the kernel and runs a basic set of tests to
verify if kprobes, jprobes and kretprobes run fine on the kernel. In case
of an error, it'll print out a message with a "BUG" prefix.

This is a start; we intend to add more tests to this bucket over time.

Thanks to Jim Keniston and Masami Hiramatsu for comments and suggestions.

Tested on x86 (32/64) and powerpc.
Signed-off-by: NAnanth N Mavinakayanahalli <ananth@in.ibm.com>
Acked-by: NMasami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>