1 files changed, 29 insertions, 7 deletions

diff --git a/arch/sparc64/kernel/process.c b/arch/sparc64/kernel/process.c
index 0f60547c24d..fc8137a21ce 100644
--- a/arch/sparc64/kernel/process.c
+++ b/arch/sparc64/kernel/process.c
@@ -304,6 +304,19 @@ void show_regs(struct pt_regs *regs)
 struct global_reg_snapshot global_reg_snapshot[NR_CPUS];
 static DEFINE_SPINLOCK(global_reg_snapshot_lock);
 
+static bool kstack_valid(struct thread_info *tp, struct reg_window *rw)
+{
+	unsigned long thread_base, fp;
+
+	thread_base = (unsigned long) tp;
+	fp = (unsigned long) rw;
+
+	if (fp < (thread_base + sizeof(struct thread_info)) ||
+	    fp >= (thread_base + THREAD_SIZE))
+		return false;
+	return true;
+}
+
 static void __global_reg_self(struct thread_info *tp, struct pt_regs *regs,
 			      int this_cpu)
 {
@@ -315,14 +328,22 @@ static void __global_reg_self(struct thread_info *tp, struct pt_regs *regs,
 	global_reg_snapshot[this_cpu].o7 = regs->u_regs[UREG_I7];
 
 	if (regs->tstate & TSTATE_PRIV) {
+		struct thread_info *tp = current_thread_info();
 		struct reg_window *rw;
 
 		rw = (struct reg_window *)
 			(regs->u_regs[UREG_FP] + STACK_BIAS);
-		global_reg_snapshot[this_cpu].i7 = rw->ins[7];
-	} else
+		if (kstack_valid(tp, rw)) {
+			global_reg_snapshot[this_cpu].i7 = rw->ins[7];
+			rw = (struct reg_window *)
+				(rw->ins[6] + STACK_BIAS);
+			if (kstack_valid(tp, rw))
+				global_reg_snapshot[this_cpu].rpc = rw->ins[7];
+		}
+	} else {
 		global_reg_snapshot[this_cpu].i7 = 0;
-
+		global_reg_snapshot[this_cpu].rpc = 0;
+	}
 	global_reg_snapshot[this_cpu].thread = tp;
 }
 
@@ -375,13 +396,14 @@ static void sysrq_handle_globreg(int key, struct tty_struct *tty)
 		       ((tp && tp->task) ? tp->task->pid : -1));
 
 		if (gp->tstate & TSTATE_PRIV) {
-			printk("             TPC[%pS] O7[%pS] I7[%pS]\n",
+			printk("             TPC[%pS] O7[%pS] I7[%pS] RPC[%pS]\n",
 			       (void *) gp->tpc,
 			       (void *) gp->o7,
-			       (void *) gp->i7);
+			       (void *) gp->i7,
+			       (void *) gp->rpc);
 		} else {
-			printk("             TPC[%lx] O7[%lx] I7[%lx]\n",
-			       gp->tpc, gp->o7, gp->i7);
+			printk("             TPC[%lx] O7[%lx] I7[%lx] RPC[%lx]\n",
+			       gp->tpc, gp->o7, gp->i7, gp->rpc);
 		}
 	}