Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer fixes from Thomas Gleixner:
 "The itimer removal one is not strictly a fix, but I really wanted to
  avoid a rebase of the urgent ones."

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Revert "clocksource: Load the ACPI PM clocksource asynchronously"
  clockevents: tTack broadcast device mode change in tick_broadcast_switch_to_oneshot()
  itimer: Use printk_once instead of WARN_ONCE
  nohz: Fix stale jiffies update in tick_nohz_restart()
  tick: Document TICK_ONESHOT config option
  proc: stats: Use arch_idle_time for idle and iowait times if available
  itimer: Schedule silent NULL pointer fixup in setitimer() for removal

7 files changed, 59 insertions, 27 deletions

diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
index 709e08e9a222..03ca210406ed 100644
--- a/Documentation/feature-removal-schedule.txt
+++ b/Documentation/feature-removal-schedule.txt
@@ -531,3 +531,11 @@ Why:	There appear to be no production users of the get_robust_list syscall,
         of ASLR. It was only ever intended for debugging, so it should be
         removed.
 Who:    Kees Cook <keescook@chromium.org>
+
+----------------------------
+
+What:   setitimer accepts user NULL pointer (value)
+When:   3.6
+Why:    setitimer is not returning -EFAULT if user pointer is NULL. This
+        violates the spec.
+Who:    Sasikantha Babu <sasikanth.v19@gmail.com>
diff --git a/drivers/clocksource/acpi_pm.c b/drivers/clocksource/acpi_pm.c
index 82e882028fcf..6b5cf02c35c8 100644
--- a/drivers/clocksource/acpi_pm.c
+++ b/drivers/clocksource/acpi_pm.c
@@ -23,7 +23,6 @@
 #include <linux/init.h>
 #include <linux/pci.h>
 #include <linux/delay.h>
-#include <linux/async.h>
 #include <asm/io.h>
 
 /*
@@ -180,15 +179,17 @@ static int verify_pmtmr_rate(void)
 /* Number of reads we try to get two different values */
 #define ACPI_PM_READ_CHECKS 10000
 
-static void __init acpi_pm_clocksource_async(void *unused, async_cookie_t cookie)
+static int __init init_acpi_pm_clocksource(void)
 {
         cycle_t value1, value2;
         unsigned int i, j = 0;
 
+        if (!pmtmr_ioport)
+                return -ENODEV;
 
         /* "verify" this timing source: */
         for (j = 0; j < ACPI_PM_MONOTONICITY_CHECKS; j++) {
-                usleep_range(100 * j, 100 * j + 100);
+                udelay(100 * j);
                 value1 = clocksource_acpi_pm.read(&clocksource_acpi_pm);
                 for (i = 0; i < ACPI_PM_READ_CHECKS; i++) {
                         value2 = clocksource_acpi_pm.read(&clocksource_acpi_pm);
@@ -202,34 +203,25 @@ static void __init acpi_pm_clocksource_async(void *unused, async_cookie_t cookie
                                " 0x%#llx, 0x%#llx - aborting.\n",
                                value1, value2);
                         pmtmr_ioport = 0;
-                        return;
+                        return -EINVAL;
                 }
                 if (i == ACPI_PM_READ_CHECKS) {
                         printk(KERN_INFO "PM-Timer failed consistency check "
                                " (0x%#llx) - aborting.\n", value1);
                         pmtmr_ioport = 0;
-                        return;
+                        return -ENODEV;
                 }
         }
 
         if (verify_pmtmr_rate() != 0){
                 pmtmr_ioport = 0;
-                return;
+                return -ENODEV;
         }
 
-        clocksource_register_hz(&clocksource_acpi_pm,
+        return clocksource_register_hz(&clocksource_acpi_pm,
                                                 PMTMR_TICKS_PER_SEC);
 }
 
-static int __init init_acpi_pm_clocksource(void)
-{
-        if (!pmtmr_ioport)
-                return -ENODEV;
-
-        async_schedule(acpi_pm_clocksource_async, NULL);
-        return 0;
-}
-
 /* We use fs_initcall because we want the PCI fixups to have run
  * but we still need to load before device_initcall
  */
diff --git a/fs/proc/stat.c b/fs/proc/stat.c
index 6a0c62d6e442..64c3b3172367 100644
--- a/fs/proc/stat.c
+++ b/fs/proc/stat.c
@@ -18,19 +18,39 @@
 #ifndef arch_irq_stat
 #define arch_irq_stat() 0
 #endif
-#ifndef arch_idle_time
-#define arch_idle_time(cpu) 0
-#endif
+
+#ifdef arch_idle_time
+
+static cputime64_t get_idle_time(int cpu)
+{
+        cputime64_t idle;
+
+        idle = kcpustat_cpu(cpu).cpustat[CPUTIME_IDLE];
+        if (cpu_online(cpu) && !nr_iowait_cpu(cpu))
+                idle += arch_idle_time(cpu);
+        return idle;
+}
+
+static cputime64_t get_iowait_time(int cpu)
+{
+        cputime64_t iowait;
+
+        iowait = kcpustat_cpu(cpu).cpustat[CPUTIME_IOWAIT];
+        if (cpu_online(cpu) && nr_iowait_cpu(cpu))
+                iowait += arch_idle_time(cpu);
+        return iowait;
+}
+
+#else
 
 static u64 get_idle_time(int cpu)
 {
         u64 idle, idle_time = get_cpu_idle_time_us(cpu, NULL);
 
-        if (idle_time == -1ULL) {
+        if (idle_time == -1ULL)
                 /* !NO_HZ so we can rely on cpustat.idle */
                 idle = kcpustat_cpu(cpu).cpustat[CPUTIME_IDLE];
-                idle += arch_idle_time(cpu);
-        } else
+        else
                 idle = usecs_to_cputime64(idle_time);
 
         return idle;
@@ -49,6 +69,8 @@ static u64 get_iowait_time(int cpu)
         return iowait;
 }
 
+#endif
+
 static int show_stat(struct seq_file *p, void *v)
 {
         int i, j;
diff --git a/kernel/itimer.c b/kernel/itimer.c
index 22000c3db0dd..8d262b467573 100644
--- a/kernel/itimer.c
+++ b/kernel/itimer.c
@@ -284,8 +284,12 @@ SYSCALL_DEFINE3(setitimer, int, which, struct itimerval __user *, value,
         if (value) {
                 if(copy_from_user(&set_buffer, value, sizeof(set_buffer)))
                         return -EFAULT;
-        } else
-                memset((char *) &set_buffer, 0, sizeof(set_buffer));
+        } else {
+                memset(&set_buffer, 0, sizeof(set_buffer));
+                printk_once(KERN_WARNING "%s calls setitimer() with new_value NULL pointer."
+                            " Misfeature support will be removed\n",
+                            current->comm);
+        }
 
         error = do_setitimer(which, &set_buffer, ovalue ? &get_buffer : NULL);
         if (error || !ovalue)
diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig
index 2cf9cc7aa103..a20dc8a3c949 100644
--- a/