From cc9dffb244ee6ef5e6d0ca5e7c1dda76b589e909 Mon Sep 17 00:00:00 2001
From: Robert Richter <robert.richter@amd.com>
Date: Sat, 17 Jan 2009 17:13:27 +0100
Subject: [PATCH] --- yaml --- r: 129986 b: refs/heads/master c:
 fdb6a8f4db813b4e50f4e975efe6be12ba5bf460 h: refs/heads/master v: v3

---
 [refs]                              | 2 +-
 trunk/drivers/oprofile/cpu_buffer.c | 5 +++++
 trunk/drivers/oprofile/cpu_buffer.h | 7 +++++++
 3 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 3a03f0e48b07..a3b13b72430f 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: c903ff837909ccada51243307d4239f86af40179
+refs/heads/master: fdb6a8f4db813b4e50f4e975efe6be12ba5bf460
diff --git a/trunk/drivers/oprofile/cpu_buffer.c b/trunk/drivers/oprofile/cpu_buffer.c
index 2e03b6d796d3..e76d715e4342 100644
--- a/trunk/drivers/oprofile/cpu_buffer.c
+++ b/trunk/drivers/oprofile/cpu_buffer.c
@@ -393,16 +393,21 @@ oprofile_write_reserve(struct op_entry *entry, struct pt_regs * const regs,
 	return;
 
 fail:
+	entry->event = NULL;
 	cpu_buf->sample_lost_overflow++;
 }
 
 int oprofile_add_data(struct op_entry *entry, unsigned long val)
 {
+	if (!entry->event)
+		return 0;
 	return op_cpu_buffer_add_data(entry, val);
 }
 
 int oprofile_write_commit(struct op_entry *entry)
 {
+	if (!entry->event)
+		return -EINVAL;
 	return op_cpu_buffer_write_commit(entry);
 }
 
diff --git a/trunk/drivers/oprofile/cpu_buffer.h b/trunk/drivers/oprofile/cpu_buffer.h
index 63f81c44846a..272995d20293 100644
--- a/trunk/drivers/oprofile/cpu_buffer.h
+++ b/trunk/drivers/oprofile/cpu_buffer.h
@@ -66,6 +66,13 @@ static inline void op_cpu_buffer_reset(int cpu)
 	cpu_buf->last_task = NULL;
 }
 
+/*
+ * op_cpu_buffer_add_data() and op_cpu_buffer_write_commit() may be
+ * called only if op_cpu_buffer_write_reserve() did not return NULL or
+ * entry->event != NULL, otherwise entry->size or entry->event will be
+ * used uninitialized.
+ */
+
 struct op_sample
 *op_cpu_buffer_write_reserve(struct op_entry *entry, unsigned long size);
 int op_cpu_buffer_write_commit(struct op_entry *entry);