sparc64: Fix stack tracing through trap frames.

The offset to the pt_regs area was wrong, so we weren't
looking at the right location for the magic cookie.

A trap frame is composed of a "struct sparc_stackf" then
a "struct pt_regs", the code was using "struct reg_window"
instead of "struct sparc_stackf".
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

arch/sparc64/kernel/stacktrace.c

@@ -19,7 +19,7 @@ void save_stack_trace(struct stack_trace *trace)
 	fp = ksp + STACK_BIAS;
 	thread_base = (unsigned long) tp;
 	do {
-		struct reg_window *rw;
+		struct sparc_stackf *sf;
 		struct pt_regs *regs;
 		unsigned long pc;
 
@@ -28,15 +28,17 @@ void save_stack_trace(struct stack_trace *trace)
 		    fp >= (thread_base + THREAD_SIZE))
 			break;
 
-		rw = (struct reg_window *) fp;
-		regs = (struct pt_regs *) (rw + 1);
+		sf = (struct sparc_stackf *) fp;
+		regs = (struct pt_regs *) (sf + 1);
 
 		if ((regs->magic & ~0x1ff) == PT_REGS_MAGIC) {
+			if (!(regs->tstate & TSTATE_PRIV))
+				break;
 			pc = regs->tpc;
 			fp = regs->u_regs[UREG_I6] + STACK_BIAS;
 		} else {
-			pc = rw->ins[7];
-			fp = rw->ins[6] + STACK_BIAS;
+			pc = sf->callers_pc;
+			fp = (unsigned long)sf->fp + STACK_BIAS;
 		}
 
 		if (trace->skip > 0)

arch/sparc64/kernel/traps.c

@@ -2116,7 +2116,7 @@ void show_stack(struct task_struct *tsk, unsigned long *_ksp)
 	printk("\n");
 #endif
 	do {
-		struct reg_window *rw;
+		struct sparc_stackf *sf;
 		struct pt_regs *regs;
 		unsigned long pc;
 
@@ -2124,15 +2124,17 @@ void show_stack(struct task_struct *tsk, unsigned long *_ksp)
 		if (fp < (thread_base + sizeof(struct thread_info)) ||
 		    fp >= (thread_base + THREAD_SIZE))
 			break;
-		rw = (struct reg_window *)fp;
-		regs = (struct pt_regs *) (rw + 1);
+		sf = (struct sparc_stackf *) fp;
+		regs = (struct pt_regs *) (sf + 1);
 
 		if ((regs->magic & ~0x1ff) == PT_REGS_MAGIC) {
+			if (!(regs->tstate & TSTATE_PRIV))
+				break;
 			pc = regs->tpc;
 			fp = regs->u_regs[UREG_I6] + STACK_BIAS;
 		} else {
-			pc = rw->ins[7];
-			fp = rw->ins[6] + STACK_BIAS;
+			pc = sf->callers_pc;
+			fp = (unsigned long)sf->fp + STACK_BIAS;
 		}
 
 		printk(" [%016lx] ", pc);