[PATCH] uml: use kallsyms when dumping stack

This patch makes UML use print_symbol() when dumping the stack.  It is not yet
complete (the i386 version uses the frame pointers to walk the stack, for
instance), but should be at least enough.

Also, it uses bust_spinlock() when dumping errors to help them reach the
console.  This appears not to be enough - however I analyzed the UML console
code, and it seems that UML console don't get flushed *at all* when exiting.
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade_spam@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/um/kernel/sysrq.c

@@ -14,23 +14,23 @@
 
 void show_trace(unsigned long * stack)
 {
-        int i;
+	/* XXX: Copy the CONFIG_FRAME_POINTER stack-walking backtrace from
+	 * arch/i386/kernel/traps.c. */
         unsigned long addr;
 
         if (!stack)
                 stack = (unsigned long*) &stack;
 
-        printk("Call Trace:\n");
-        i = 1;
+        printk("Call Trace: \n");
         while (((long) stack & (THREAD_SIZE-1)) != 0) {
                 addr = *stack++;
 		if (__kernel_text_address(addr)) {
-			printk("[<%08lx>] ", addr);
-			print_symbol("%s", addr);
+			printk(" [<%08lx>]", addr);
+			print_symbol(" %s", addr);
 			printk("\n");
-			i++;
                 }
         }
+        printk("\n");
 }
 
 /*
@@ -48,4 +48,3 @@ void show_stack(struct task_struct *task, unsigned long *sp)
 {
 	show_trace(sp);
 }
-

arch/um/kernel/um_arch.c

@@ -405,9 +405,9 @@ extern int uml_exitcode;
 static int panic_exit(struct notifier_block *self, unsigned long unused1,
 		      void *unused2)
 {
-#ifdef CONFIG_MAGIC_SYSRQ
-	handle_sysrq('p', &current->thread.regs, NULL);
-#endif
+	bust_spinlocks(1);
+	show_regs(&(current->thread.regs));
+	bust_spinlocks(0);
 	uml_exitcode = 1;
 	machine_halt();
 	return(0);