Merge commit 'v2.6.36' into wip-merge-2.6.36

Conflicts:
	Makefile
	arch/x86/include/asm/unistd_32.h
	arch/x86/kernel/syscall_table_32.S
	kernel/sched.c
	kernel/time/tick-sched.c

Relevant API and functions changes (solved in this commit):
- (API) .enqueue_task() (enqueue_task_litmus),
  dequeue_task() (dequeue_task_litmus),
  [litmus/sched_litmus.c]
- (API) .select_task_rq() (select_task_rq_litmus)
  [litmus/sched_litmus.c]
- (API) sysrq_dump_trace_buffer() and sysrq_handle_kill_rt_tasks()
  [litmus/sched_trace.c]
- struct kfifo internal buffer name changed (buffer -> buf)
  [litmus/sched_trace.c]
- add_wait_queue_exclusive_locked -> __add_wait_queue_tail_exclusive
  [litmus/fmlp.c]
- syscall numbers for both x86_32 and x86_64

1 files changed, 61 insertions, 7 deletions

diff --git a/kernel/printk.c b/kernel/printk.c
index ee54355cfdf1..9dc8ea140426 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -33,9 +33,12 @@
 #include <linux/bootmem.h>
 #include <linux/syscalls.h>
 #include <linux/kexec.h>
+#include <linux/kdb.h>
 #include <linux/ratelimit.h>
 #include <linux/kmsg_dump.h>
 #include <linux/syslog.h>
+#include <linux/cpu.h>
+#include <linux/notifier.h>
 
 #include <asm/uaccess.h>
 
@@ -420,6 +423,22 @@ SYSCALL_DEFINE3(syslog, int, type, char __user *, buf, int, len)
         return do_syslog(type, buf, len, SYSLOG_FROM_CALL);
 }
 
+#ifdef  CONFIG_KGDB_KDB
+/* kdb dmesg command needs access to the syslog buffer.  do_syslog()
+ * uses locks so it cannot be used during debugging.  Just tell kdb
+ * where the start and end of the physical and logical logs are.  This
+ * is equivalent to do_syslog(3).
+ */
+void kdb_syslog_data(char *syslog_data[4])
+{
+        syslog_data[0] = log_buf;
+        syslog_data[1] = log_buf + log_buf_len;
+        syslog_data[2] = log_buf + log_end -
+                (logged_chars < log_buf_len ? logged_chars : log_buf_len);
+        syslog_data[3] = log_buf + log_end;
+}
+#endif  /* CONFIG_KGDB_KDB */
+
 /*
  * Call the console drivers on a range of log_buf
  */
@@ -593,6 +612,14 @@ asmlinkage int printk(const char *fmt, ...)
         va_list args;
         int r;
 
+#ifdef CONFIG_KGDB_KDB
+        if (unlikely(kdb_trap_printk)) {
+                va_start(args, fmt);
+                r = vkdb_printf(fmt, args);
+                va_end(args);
+                return r;
+        }
+#endif
         va_start(args, fmt);
         r = vprintk(fmt, args);
         va_end(args);
@@ -970,6 +997,32 @@ void resume_console(void)
 }
 
 /**
+ * console_cpu_notify - print deferred console messages after CPU hotplug
+ * @self: notifier struct
+ * @action: CPU hotplug event
+ * @hcpu: unused
+ *
+ * If printk() is called from a CPU that is not online yet, the messages
+ * will be spooled but will not show up on the console.  This function is
+ * called when a new CPU comes online (or fails to come up), and ensures
+ * that any such output gets printed.
+ */
+static int __cpuinit console_cpu_notify(struct notifier_block *self,
+        unsigned long action, void *hcpu)
+{
+        switch (action) {
+        case CPU_ONLINE:
+        case CPU_DEAD:
+        case CPU_DYING:
+        case CPU_DOWN_FAILED:
+        case CPU_UP_CANCELED:
+                acquire_console_sem();
+                release_console_sem();
+        }
+        return NOTIFY_OK;
+}
+
+/**
  * acquire_console_sem - lock the console system for exclusive use.
  *
  * Acquires a semaphore which guarantees that the caller has
@@ -1356,7 +1409,7 @@ int unregister_console(struct console *console)
 }
 EXPORT_SYMBOL(unregister_console);
 
-static int __init disable_boot_consoles(void)
+static int __init printk_late_init(void)
 {
         struct console *con;
 
@@ -1367,9 +1420,10 @@ static int __init disable_boot_consoles(void)
                         unregister_console(con);
                 }
         }
+        hotcpu_notifier(console_cpu_notify, 0);
         return 0;
 }
-late_initcall(disable_boot_consoles);
+late_initcall(printk_late_init);
 
 #if defined CONFIG_PRINTK
 
@@ -1505,9 +1559,9 @@ void kmsg_dump(enum kmsg_dump_reason reason)
         chars = logged_chars;
         spin_unlock_irqrestore(&logbuf_lock, flags);
 
-        if (logged_chars > end) {
-                s1 = log_buf + log_buf_len - logged_chars + end;
-                l1 = logged_chars - end;
+        if (chars > end) {
+                s1 = log_buf + log_buf_len - chars + end;
+                l1 = chars - end;
 
                 s2 = log_buf;
                 l2 = end;
@@ -1515,8 +1569,8 @@ void kmsg_dump(enum kmsg_dump_reason reason)
                 s1 = "";
                 l1 = 0;
 
-                s2 = log_buf + end - logged_chars;
-                l2 = logged_chars;
+                s2 = log_buf + end - chars;
+                l2 = chars;
         }
 
         if (!spin_trylock_irqsave(&dump_list_lock, flags)) {