x86, bts: fix unlock problem in ds.c

Fix a problem where ds_request() returned an error without releasing the
ds lock.

Reported-by: Stephane Eranian <eranian@gmail.com>
Signed-off-by: Markus Metzger <markus.t.metzger@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 2 insertions, 1 deletions

diff --git a/arch/x86/kernel/ds.c b/arch/x86/kernel/ds.c
index 2b69994fd3a8..ac1d5b0586ba 100644
--- a/arch/x86/kernel/ds.c
+++ b/arch/x86/kernel/ds.c
@@ -384,8 +384,9 @@ static int ds_request(struct task_struct *task, void *base, size_t size,
 
         spin_lock(&ds_lock);
 
+        error = -EPERM;
         if (!check_tracer(task))
-                return -EPERM;
+                goto out_unlock;
 
         error = -ENOMEM;
         context = ds_alloc_context(task);