From 1d11526b09271a5b5141689e6804b288292ea9a3 Mon Sep 17 00:00:00 2001
From: Andrey Vagin <avagin@openvz.org>
Date: Tue, 30 Aug 2011 12:32:36 +0400
Subject: [PATCH] --- yaml --- r: 263646 b: refs/heads/master c:
 20afc60f892d285fde179ead4b24e6a7938c2f1b h: refs/heads/master v: v3

---
 [refs]                                 | 2 +-
 trunk/arch/x86/kernel/cpu/perf_event.c | 3 +++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 62845d3ebd12..6902134bacc3 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 7f310a5d4e8525ac0cc2f58c973d2100ce034410
+refs/heads/master: 20afc60f892d285fde179ead4b24e6a7938c2f1b
diff --git a/trunk/arch/x86/kernel/cpu/perf_event.c b/trunk/arch/x86/kernel/cpu/perf_event.c
index 4ee3abf20ed6..cfa62ec090ec 100644
--- a/trunk/arch/x86/kernel/cpu/perf_event.c
+++ b/trunk/arch/x86/kernel/cpu/perf_event.c
@@ -1900,6 +1900,9 @@ perf_callchain_user(struct perf_callchain_entry *entry, struct pt_regs *regs)
 
 	perf_callchain_store(entry, regs->ip);
 
+	if (!current->mm)
+		return;
+
 	if (perf_callchain_user32(regs, entry))
 		return;