From: Paul Mundt <lethal@linux-sh.org>
Date: Fri, 6 Nov 2009 08:23:33 +0000 (+0900)
Subject: sh: unwinder: Fix up invalid PC refetch in dwarf unwinder.
X-Git-Tag: v2.6.32-rc7~62^2~2
X-Git-Url: https://openfabrics.org/gitweb/?a=commitdiff_plain;h=421b541110b20ccff1a7ff3245439cb24efe9812;p=~shefty%2Frdma-dev.git

sh: unwinder: Fix up invalid PC refetch in dwarf unwinder.

The dwarf unwinder presently attempts to provide a sane PC value if none
is provided, however the logic is broken and cases where a previous valid
dwarf frame exists along with a bogus PC value can still proceed. This
fixes up the test and prevents the unwinder from blowing up.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
---

diff --git a/arch/sh/kernel/dwarf.c b/arch/sh/kernel/dwarf.c
index 2d07084e488..d76a23170db 100644
--- a/arch/sh/kernel/dwarf.c
+++ b/arch/sh/kernel/dwarf.c
@@ -555,7 +555,7 @@ struct dwarf_frame * dwarf_unwind_stack(unsigned long pc,
 	 * NOTE: the return address is guaranteed to be setup by the
 	 * time this function makes its first function call.
 	 */
-	if (!pc && !prev)
+	if (!pc || !prev)
 		pc = (unsigned long)current_text_addr();
 
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER