[PATCH v2] drm/tegra: Correct idr_alloc() minimum id

[Dmitry Osipenko]

The client ID 0 is reserved by the host1x/cdma to mark the timeout timer
work as already been scheduled and context ID is used as the clients one.
This fixes spurious CDMA timeouts.

Fixes: bdd2f9cd10eb ("drm/tegra: Don't leak kernel pointer to userspace")
Signed-off-by: Dmitry Osipenko <digetx at gmail.com>
---

v2: Changed the commit description, now explains the cause of CDMA timeouts.

 drivers/gpu/drm/tegra/drm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/tegra/drm.c b/drivers/gpu/drm/tegra/drm.c
index c5844a065681..489cb32453f7 100644
--- a/drivers/gpu/drm/tegra/drm.c
+++ b/drivers/gpu/drm/tegra/drm.c
@@ -548,7 +548,7 @@ static int tegra_client_open(struct tegra_drm_file *fpriv,
 	if (err < 0)
 		return err;
 
-	err = idr_alloc(&fpriv->contexts, context, 0, 0, GFP_KERNEL);
+	err = idr_alloc(&fpriv->contexts, context, 1, 0, GFP_KERNEL);
 	if (err < 0) {
 		client->ops->close_channel(context);
 		return err;
-- 
2.13.0