panic: Allow warnings to set different taint flags

[safe/jmp/linux-2.6] / kernel / panic.c

diff --git a/kernel/panic.c b/kernel/panic.c
index bcdef26..8b821bc 100644 (file)
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -10,6 +10,7 @@
  */
 #include <linux/debug_locks.h>
 #include <linux/interrupt.h>
+#include <linux/kmsg_dump.h>
 #include <linux/kallsyms.h>
 #include <linux/notifier.h>
 #include <linux/module.h>
@@ -35,15 +36,36 @@ ATOMIC_NOTIFIER_HEAD(panic_notifier_list);
 
 EXPORT_SYMBOL(panic_notifier_list);
 
-static long no_blink(long time)
-{
-       return 0;
-}
-
 /* Returns how long it waited in ms */
 long (*panic_blink)(long time);
 EXPORT_SYMBOL(panic_blink);
 
+static void panic_blink_one_second(void)
+{
+       static long i = 0, end;
+
+       if (panic_blink) {
+               end = i + MSEC_PER_SEC;
+
+               while (i < end) {
+                       i += panic_blink(i);
+                       mdelay(1);
+                       i++;
+               }
+       } else {
+               /*
+                * When running under a hypervisor a small mdelay may get
+                * rounded up to the hypervisor timeslice. For example, with
+                * a 1ms in 10ms hypervisor timeslice we might inflate a
+                * mdelay(1) loop by 10x.
+                *
+                * If we have nothing to blink, spin on 1 second calls to
+                * mdelay to avoid this.
+                */
+               mdelay(MSEC_PER_SEC);
+       }
+}
+
 /**
  *     panic - halt the system
  *     @fmt: The text string to print
@@ -81,6 +103,8 @@ NORET_TYPE void panic(const char * fmt, ...)
         */
        crash_kexec(NULL);
 
+       kmsg_dump(KMSG_DUMP_PANIC);
+
        /*
         * Note smp_send_stop is the usual smp shutdown function, which
         * unfortunately means it may not be hardened to work in a panic
@@ -90,8 +114,7 @@ NORET_TYPE void panic(const char * fmt, ...)
 
        atomic_notifier_call_chain(&panic_notifier_list, 0, buf);
 
-       if (!panic_blink)
-               panic_blink = no_blink;
+       bust_spinlocks(0);
 
        if (panic_timeout > 0) {
                /*
@@ -100,11 +123,9 @@ NORET_TYPE void panic(const char * fmt, ...)
                 */
                printk(KERN_EMERG "Rebooting in %d seconds..", panic_timeout);
 
-               for (i = 0; i < panic_timeout*1000; ) {
+               for (i = 0; i < panic_timeout; i++) {
                        touch_nmi_watchdog();
-                       i += panic_blink(i);
-                       mdelay(1);
-                       i++;
+                       panic_blink_one_second();
                }
                /*
                 * This will not be a clean reboot, with everything
@@ -130,13 +151,10 @@ NORET_TYPE void panic(const char * fmt, ...)
        }
 #endif
        local_irq_enable();
-       for (i = 0; ; ) {
+       while (1) {
                touch_softlockup_watchdog();
-               i += panic_blink(i);
-               mdelay(1);
-               i++;
+               panic_blink_one_second();
        }
-       bust_spinlocks(0);
 }
 
 EXPORT_SYMBOL(panic);
@@ -338,6 +356,7 @@ void oops_exit(void)
 {
        do_oops_enter_exit();
        print_oops_end_marker();
+       kmsg_dump(KMSG_DUMP_OOPS);
 }
 
 #ifdef WANT_WARN_ON_SLOWPATH
@@ -346,7 +365,8 @@ struct slowpath_args {
        va_list args;
 };
 
-static void warn_slowpath_common(const char *file, int line, void *caller, struct slowpath_args *args)
+static void warn_slowpath_common(const char *file, int line, void *caller,
+                                unsigned taint, struct slowpath_args *args)
 {
        const char *board;
 
@@ -362,7 +382,7 @@ static void warn_slowpath_common(const char *file, int line, void *caller, struc
        print_modules();
        dump_stack();
        print_oops_end_marker();
-       add_taint(TAINT_WARN);
+       add_taint(taint);
 }
 
 void warn_slowpath_fmt(const char *file, int line, const char *fmt, ...)
@@ -371,14 +391,29 @@ void warn_slowpath_fmt(const char *file, int line, const char *fmt, ...)
 
        args.fmt = fmt;
        va_start(args.args, fmt);
-       warn_slowpath_common(file, line, __builtin_return_address(0), &args);
+       warn_slowpath_common(file, line, __builtin_return_address(0),
+                            TAINT_WARN, &args);
        va_end(args.args);
 }
 EXPORT_SYMBOL(warn_slowpath_fmt);
 
+void warn_slowpath_fmt_taint(const char *file, int line,
+                            unsigned taint, const char *fmt, ...)
+{
+       struct slowpath_args args;
+
+       args.fmt = fmt;
+       va_start(args.args, fmt);
+       warn_slowpath_common(file, line, __builtin_return_address(0),
+                            taint, &args);
+       va_end(args.args);
+}
+EXPORT_SYMBOL(warn_slowpath_fmt_taint);
+
 void warn_slowpath_null(const char *file, int line)
 {
-       warn_slowpath_common(file, line, __builtin_return_address(0), NULL);
+       warn_slowpath_common(file, line, __builtin_return_address(0),
+                            TAINT_WARN, NULL);
 }
 EXPORT_SYMBOL(warn_slowpath_null);
 #endif