[PATCH] i386: handle_BUG(): don't print garbage if debug info unavailable

handle_BUG() tries to print file and line number even when they're not
available (CONFIG_DEBUG_BUGVERBOSE is not set.) Change this to print a
message stating info is unavailable instead of printing a misleading
message.

Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 20 insertions, 20 deletions

diff --git a/arch/i386/kernel/traps.c b/arch/i386/kernel/traps.c
index 5cfd4f42eeba..313ac1f7dc5a 100644
--- a/arch/i386/kernel/traps.c
+++ b/arch/i386/kernel/traps.c
@@ -324,35 +324,35 @@ void show_registers(struct pt_regs *regs)
 
 static void handle_BUG(struct pt_regs *regs)
 {
+        unsigned long eip = regs->eip;
         unsigned short ud2;
-        unsigned short line;
-        char *file;
-        char c;
-        unsigned long eip;
-
-        eip = regs->eip;
 
         if (eip < PAGE_OFFSET)
-                goto no_bug;
+                return;
         if (__get_user(ud2, (unsigned short __user *)eip))
-                goto no_bug;
+                return;
         if (ud2 != 0x0b0f)
-                goto no_bug;
-        if (__get_user(line, (unsigned short __user *)(eip + 2)))
-                goto bug;
-        if (__get_user(file, (char * __user *)(eip + 4)) ||
-                (unsigned long)file < PAGE_OFFSET || __get_user(c, file))
-                file = "<bad filename>";
+                return;
 
         printk(KERN_EMERG "------------[ cut here ]------------\n");
-        printk(KERN_EMERG "kernel BUG at %s:%d!\n", file, line);
 
-no_bug:
-        return;
+#ifdef CONFIG_DEBUG_BUGVERBOSE
+        do {
+                unsigned short line;
+                char *file;
+                char c;
 
-        /* Here we know it was a BUG but file-n-line is unavailable */
-bug:
-        printk(KERN_EMERG "Kernel BUG\n");
+                if (__get_user(line, (unsigned short __user *)(eip + 2)))
+                        break;
+                if (__get_user(file, (char * __user *)(eip + 4)) ||
+                    (unsigned long)file < PAGE_OFFSET || __get_user(c, file))
+                        file = "<bad filename>";
+
+                printk(KERN_EMERG "kernel BUG at %s:%d!\n", file, line);
+                return;
+        } while (0);
+#endif
+        printk(KERN_EMERG "Kernel BUG at [verbose debug info unavailable]\n");
 }
 
 /* This is gone through when something in the kernel