1 files changed, 78 insertions, 58 deletions

diff --git a/kernel/panic.c b/kernel/panic.c
index 32fe4eff1b89..874ecf1307ae 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -8,19 +8,19 @@
  * This function is used through-out the kernel (including mm and fs)
  * to indicate a major problem.
  */
+#include <linux/debug_locks.h>
+#include <linux/interrupt.h>
+#include <linux/kallsyms.h>
+#include <linux/notifier.h>
 #include <linux/module.h>
-#include <linux/sched.h>
-#include <linux/delay.h>
+#include <linux/random.h>
 #include <linux/reboot.h>
-#include <linux/notifier.h>
-#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/kexec.h>
+#include <linux/sched.h>
 #include <linux/sysrq.h>
-#include <linux/interrupt.h>
+#include <linux/init.h>
 #include <linux/nmi.h>
-#include <linux/kexec.h>
-#include <linux/debug_locks.h>
-#include <linux/random.h>
-#include <linux/kallsyms.h>
 #include <linux/dmi.h>
 
 int panic_on_oops;
@@ -52,19 +52,15 @@ EXPORT_SYMBOL(panic_blink);
  *
  *      This function never returns.
  */
-
 NORET_TYPE void panic(const char * fmt, ...)
 {
-        long i;
         static char buf[1024];
         va_list args;
-#if defined(CONFIG_S390)
-        unsigned long caller = (unsigned long) __builtin_return_address(0);
-#endif
+        long i;
 
         /*
-         * It's possible to come here directly from a panic-assertion and not
-         * have preempt disabled. Some functions called from here want
+         * It's possible to come here directly from a panic-assertion and
+         * not have preempt disabled. Some functions called from here want
          * preempt to be disabled. No point enabling it later though...
          */
         preempt_disable();
@@ -77,7 +73,6 @@ NORET_TYPE void panic(const char * fmt, ...)
 #ifdef CONFIG_DEBUG_BUGVERBOSE
         dump_stack();
 #endif
-        bust_spinlocks(0);
 
         /*
          * If we have crashed and we have a crash kernel loaded let it handle
@@ -86,14 +81,12 @@ NORET_TYPE void panic(const char * fmt, ...)
          */
         crash_kexec(NULL);
 
-#ifdef CONFIG_SMP
         /*
          * Note smp_send_stop is the usual smp shutdown function, which
          * unfortunately means it may not be hardened to work in a panic
          * situation.
          */
         smp_send_stop();
-#endif
 
         atomic_notifier_call_chain(&panic_notifier_list, 0, buf);
 
@@ -102,19 +95,21 @@ NORET_TYPE void panic(const char * fmt, ...)
 
         if (panic_timeout > 0) {
                 /*
-                 * Delay timeout seconds before rebooting the machine. 
-                 * We can't use the "normal" timers since we just panicked..
-                 */
-                printk(KERN_EMERG "Rebooting in %d seconds..",panic_timeout);
+                 * Delay timeout seconds before rebooting the machine.
+                 * We can't use the "normal" timers since we just panicked.
+                 */
+                printk(KERN_EMERG "Rebooting in %d seconds..", panic_timeout);
+
                 for (i = 0; i < panic_timeout*1000; ) {
                         touch_nmi_watchdog();
                         i += panic_blink(i);
                         mdelay(1);
                         i++;
                 }
-                /*      This will not be a clean reboot, with everything
-                 *      shutting down.  But if there is a chance of
-                 *      rebooting the system it will be rebooted.
+                /*
+                 * This will not be a clean reboot, with everything
+                 * shutting down.  But if there is a chance of
+                 * rebooting the system it will be rebooted.
                  */
                 emergency_restart();
         }
@@ -127,38 +122,44 @@ NORET_TYPE void panic(const char * fmt, ...)
         }
 #endif
 #if defined(CONFIG_S390)
-        disabled_wait(caller);
+        {
+                unsigned long caller;
+
+                caller = (unsigned long)__builtin_return_address(0);
+                disabled_wait(caller);
+        }
 #endif
         local_irq_enable();
-        for (i = 0;;) {
+        for (i = 0; ; ) {
                 touch_softlockup_watchdog();
                 i += panic_blink(i);
                 mdelay(1);
                 i++;
         }
+        bust_spinlocks(0);
 }
 
 EXPORT_SYMBOL(panic);
 
 
 struct tnt {
-        u8 bit;
-        char true;
-        char false;
+        u8      bit;
+        char    true;
+        char    false;
 };
 
 static const struct tnt tnts[] = {
-        { TAINT_PROPRIETARY_MODULE, 'P', 'G' },
-        { TAINT_FORCED_MODULE, 'F', ' ' },
-        { TAINT_UNSAFE_SMP, 'S', ' ' },
-        { TAINT_FORCED_RMMOD, 'R', ' ' },
-        { TAINT_MACHINE_CHECK, 'M', ' ' },
-        { TAINT_BAD_PAGE, 'B', ' ' },
-        { TAINT_USER, 'U', ' ' },
-        { TAINT_DIE, 'D', ' ' },
-        { TAINT_OVERRIDDEN_ACPI_TABLE, 'A', ' ' },
-        { TAINT_WARN, 'W', ' ' },
-        { TAINT_CRAP, 'C', ' ' },
+        { TAINT_PROPRIETARY_MODULE,     'P', 'G' },
+        { TAINT_FORCED_MODULE,          'F', ' ' },
+        { TAINT_UNSAFE_SMP,             'S', ' ' },
+        { TAINT_FORCED_RMMOD,           'R', ' ' },
+        { TAINT_MACHINE_CHECK,          'M', ' ' },
+        { TAINT_BAD_PAGE,               'B', ' ' },
+        { TAINT_USER,                   'U', ' ' },
+        { TAINT_DIE,                    'D', ' ' },
+        { TAINT_OVERRIDDEN_ACPI_TABLE,  'A', ' ' },
+        { TAINT_WARN,                   'W', ' ' },
+        { TAINT_CRAP,                   'C', ' ' },
 };
 
 /**
@@ -195,7 +196,8 @@ const char *print_tainted(void)
                 *s = 0;
         } else
                 snprintf(buf, sizeof(buf), "Not tainted");
-        return(buf);
+
+        return buf;
 }
 
 int test_taint(unsigned flag)
@@ -211,7 +213,16 @@ unsigned long get_taint(void)
 
 void add_taint(unsigned flag)
 {
-        debug_locks = 0; /* can't trust the integrity of the kernel anymore */
+        /*
+         * Can't trust the integrity of the kernel anymore.
+         * We don't call directly debug_locks_off() because the issue
+         * is not necessarily serious enough to set oops_in_progress to 1
+         * Also we want to keep up lockdep for staging development and
+         * post-warning case.
+         */
+        if (flag != TAINT_CRAP && flag != TAINT_WARN && __debug_locks_off())
+                printk(KERN_WARNING "Disabling lock debugging due to kernel taint\n");
+
         set_bit(flag, &tainted_mask);
 }
 EXPORT_SYMBOL(add_taint);
@@ -266,8 +277,8 @@ static void do_oops_enter_exit(void)
 }
 
 /*
- * Return true if the calling CPU is allowed to print oops-related info.  This
- * is a bit racy..
+ * Return true if the calling CPU is allowed to print oops-related info.
+ * This is a bit racy..
  */
 int oops_may_print(void)
 {
@@ -276,20 +287,22 @@ int oops_may_print(void)
 
 /*
  * Called when the architecture enters its oops handler, before it prints
- * anything.  If this is the first CPU to oops, and it's oopsing the first time
- * then let it proceed.
+ * anything.  If this is the first CPU to oops, and it's oopsing the first
+ * time then let it proceed.
  *
- * This is all enabled by the pause_on_oops kernel boot option.  We do all this
- * to ensure that oopses don't scroll off the screen.  It has the side-effect
- * of preventing later-oopsing CPUs from mucking up the display, too.
+ * This is all enabled by the pause_on_oops kernel boot option.  We do all
+ * this to ensure that oopses don't scroll off the screen.  It has the
+ * side-effect of preventing later-oopsing CPUs from mucking up the display,
+ * too.
  *
- * It turns out that the CPU which is allowed to print ends up pausing for the
- * right duration, whereas all the other CPUs pause for twice as long: once in
- * oops_enter(), once in oops_exit().
+ * It turns out that the CPU which is allowed to print ends up pausing for
+ * the right duration, whereas all the other CPUs pause for twice as long:
+ * once in oops_enter(), once in oops_exit().
  */
 void oops_enter(void)
 {
-        debug_locks_off(); /* can't trust the integrity of the kernel anymore */
+        /* can't trust the integrity of the kernel anymore: */
+        debug_locks_off();
         do_oops_enter_exit();
 }
 
@@ -327,7 +340,7 @@ void oops_exit(void)
 }
 
 #ifdef WANT_WARN_ON_SLOWPATH
-void warn_slowpath(const char *file, int line, const char *fmt, ...)
+void warn_slowpath_fmt(const char *file, int line, const char *fmt, ...)
 {
         va_list args;
         char function[KSYM_SYMBOL_LEN];
@@ -343,7 +356,7 @@ void warn_slowpath(const char *file, int line, const char *fmt, ...)
         if (board)
                 printk(KERN_WARNING "Hardware name: %s\n", board);
 
-        if (fmt) {
+        if (*fmt) {
                 va_start(args, fmt);
                 vprintk(fmt, args);
                 va_end(args);
@@ -354,7 +367,14 @@ void warn_slowpath(const char *file, int line, const char *fmt, ...)
         print_oops_end_marker();
         add_taint(TAINT_WARN);
 }
-EXPORT_SYMBOL(warn_slowpath);
+EXPORT_SYMBOL(warn_slowpath_fmt);
+
+void warn_slowpath_null(const char *file, int line)
+{
+        static const char *empty = "";
+        warn_slowpath_fmt(file, line, empty);
+}
+EXPORT_SYMBOL(warn_slowpath_null);
 #endif
 
 #ifdef CONFIG_CC_STACKPROTECTOR