3.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: "David S. Miller" <da...@davemloft.net>
[ Upstream commit 08280e6c4c2e8049ac61d9e8e3536ec1df629c0d ]
If the MM is not active, only report the top-level PC. Do not try to
access the address space.
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
arch/sparc/kernel/perf_event.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
--- a/arch/sparc/kernel/perf_event.c
+++ b/arch/sparc/kernel/perf_event.c
@@ -1428,8 +1428,6 @@ static void perf_callchain_user_64(struc
{
unsigned long ufp;
- perf_callchain_store(entry, regs->tpc);
-
ufp = regs->u_regs[UREG_I6] + STACK_BIAS;
do {
struct sparc_stackf *usf, sf;
@@ -1450,8 +1448,6 @@ static void perf_callchain_user_32(struc
{
unsigned long ufp;
- perf_callchain_store(entry, regs->tpc);
-
ufp = regs->u_regs[UREG_I6] & 0xffffffffUL;
do {
struct sparc_stackf32 *usf, sf;
@@ -1470,6 +1466,11 @@ static void perf_callchain_user_32(struc
void
perf_callchain_user(struct perf_callchain_entry *entry, struct pt_regs *regs)
{
+ perf_callchain_store(entry, regs->tpc);
+
+ if (!current->mm)
+ return;
+
flushw_user();
if (test_thread_flag(TIF_32BIT))
perf_callchain_user_32(entry, regs);
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
