From bb4fe2a3ad12ca01da545f2decc1733927877e6d Mon Sep 17 00:00:00 2001
From: Namhyung Kim <namhyung.kim@lge.com>
Date: Thu, 31 May 2012 14:43:27 +0900
Subject: [PATCH] --- yaml --- r: 310589 b: refs/heads/master c:
 114067b69e7b2c691faace0e33db2f04096f668d h: refs/heads/master i:   310587:
 225261c8ce4b34aaa962c9891726b25b2d535df4 v: v3

---
 [refs]                           |  2 +-
 trunk/include/linux/perf_event.h |  4 ++--
 trunk/tools/perf/util/session.c  | 14 +++++++++++++-
 3 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/[refs] b/[refs]
index d6a4c2802ff6..dc8364453aa3 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 472606458f3e1ced5fe3cc5f04e90a6b5a4732cf
+refs/heads/master: 114067b69e7b2c691faace0e33db2f04096f668d
diff --git a/trunk/include/linux/perf_event.h b/trunk/include/linux/perf_event.h
index f32578634d9d..1817d4015e5f 100644
--- a/trunk/include/linux/perf_event.h
+++ b/trunk/include/linux/perf_event.h
@@ -555,6 +555,8 @@ enum perf_event_type {
 	PERF_RECORD_MAX,			/* non-ABI */
 };
 
+#define PERF_MAX_STACK_DEPTH		255
+
 enum perf_callchain_context {
 	PERF_CONTEXT_HV			= (__u64)-32,
 	PERF_CONTEXT_KERNEL		= (__u64)-128,
@@ -609,8 +611,6 @@ struct perf_guest_info_callbacks {
 #include <linux/sysfs.h>
 #include <asm/local.h>
 
-#define PERF_MAX_STACK_DEPTH		255
-
 struct perf_callchain_entry {
 	__u64				nr;
 	__u64				ip[PERF_MAX_STACK_DEPTH];
diff --git a/trunk/tools/perf/util/session.c b/trunk/tools/perf/util/session.c
index 3b6f8e460a31..04d1e33f4592 100644
--- a/trunk/tools/perf/util/session.c
+++ b/trunk/tools/perf/util/session.c
@@ -300,6 +300,11 @@ int machine__resolve_callchain(struct machine *self,
 
 	callchain_cursor_reset(&callchain_cursor);
 
+	if (chain->nr > PERF_MAX_STACK_DEPTH) {
+		pr_warning("corrupted callchain. skipping...\n");
+		return 0;
+	}
+
 	for (i = 0; i < chain->nr; i++) {
 		u64 ip;
 		struct addr_location al;
@@ -318,7 +323,14 @@ int machine__resolve_callchain(struct machine *self,
 			case PERF_CONTEXT_USER:
 				cpumode = PERF_RECORD_MISC_USER;	break;
 			default:
-				break;
+				pr_debug("invalid callchain context: "
+					 "%"PRId64"\n", (s64) ip);
+				/*
+				 * It seems the callchain is corrupted.
+				 * Discard all.
+				 */
+				callchain_cursor_reset(&callchain_cursor);
+				return 0;
 			}
 			continue;
 		}