[PATCH] drm/virtio: use %llu format string form atomic64_t

Arnd Bergmann arnd at arndb.de
Wed Oct 7 03:41:21 PDT 2015

The virtgpu driver prints the last_seq variable using the %ld or
%lu format string, which does not work correctly on all architectures
and causes this compiler warning on ARM:

drivers/gpu/drm/virtio/virtgpu_fence.c: In function 'virtio_timeline_value_str':
drivers/gpu/drm/virtio/virtgpu_fence.c:64:22: warning: format '%lu' expects argument of type 'long unsigned int', but argument 4 has type 'long long int' [-Wformat=]
  snprintf(str, size, "%lu", atomic64_read(&fence->drv->last_seq));
drivers/gpu/drm/virtio/virtgpu_debugfs.c: In function 'virtio_gpu_debugfs_irq_info':
drivers/gpu/drm/virtio/virtgpu_debugfs.c:37:16: warning: format '%ld' expects argument of type 'long int', but argument 3 has type 'long long int' [-Wformat=]
  seq_printf(m, "fence %ld %lld\n",

In order to avoid the warnings, this changes the format strings to %llu
and adds a cast to u64, which makes it work the same way everywhere.

Signed-off-by: Arnd Bergmann <arnd at arndb.de>

diff --git a/drivers/gpu/drm/virtio/virtgpu_debugfs.c b/drivers/gpu/drm/virtio/virtgpu_debugfs.c
index db8b49101a8b..512263919282 100644
--- a/drivers/gpu/drm/virtio/virtgpu_debugfs.c
+++ b/drivers/gpu/drm/virtio/virtgpu_debugfs.c
@@ -34,8 +34,8 @@ virtio_gpu_debugfs_irq_info(struct seq_file *m, void *data)
 	struct drm_info_node *node = (struct drm_info_node *) m->private;
 	struct virtio_gpu_device *vgdev = node->minor->dev->dev_private;
-	seq_printf(m, "fence %ld %lld\n",
-		   atomic64_read(&vgdev->fence_drv.last_seq),
+	seq_printf(m, "fence %llu %lld\n",
+		   (u64)atomic64_read(&vgdev->fence_drv.last_seq),
 	return 0;
diff --git a/drivers/gpu/drm/virtio/virtgpu_fence.c b/drivers/gpu/drm/virtio/virtgpu_fence.c
index 1da632631dac..67097c9ce9c1 100644
--- a/drivers/gpu/drm/virtio/virtgpu_fence.c
+++ b/drivers/gpu/drm/virtio/virtgpu_fence.c
@@ -61,7 +61,7 @@ static void virtio_timeline_value_str(struct fence *f, char *str, int size)
 	struct virtio_gpu_fence *fence = to_virtio_fence(f);
-	snprintf(str, size, "%lu", atomic64_read(&fence->drv->last_seq));
+	snprintf(str, size, "%llu", (u64)atomic64_read(&fence->drv->last_seq));
 static const struct fence_ops virtio_fence_ops = {

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