drm/i915: Don't call describe_obj on NULL pointers

Reported-by: Pavel Roskin <proski@gnu.org>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=38777
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Keith Packard <keithp@keithp.com>

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 4d46441..0a893f7 100644 (file)
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -1207,13 +1207,17 @@ static int i915_context_status(struct seq_file *m, void *unused)
        if (ret)
                return ret;
 
-       seq_printf(m, "power context ");
-       describe_obj(m, dev_priv->pwrctx);
-       seq_printf(m, "\n");
+       if (dev_priv->pwrctx) {
+               seq_printf(m, "power context ");
+               describe_obj(m, dev_priv->pwrctx);
+               seq_printf(m, "\n");
+       }
 
-       seq_printf(m, "render context ");
-       describe_obj(m, dev_priv->renderctx);
-       seq_printf(m, "\n");
+       if (dev_priv->renderctx) {
+               seq_printf(m, "render context ");
+               describe_obj(m, dev_priv->renderctx);
+               seq_printf(m, "\n");
+       }
 
        mutex_unlock(&dev->mode_config.mutex);