drm/tegra: Correct idr_alloc() minimum id

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: 66ed2d4e72eb ("drm/tegra: Don't leak kernel pointer to userspace")
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: http://patchwork.freedesktop.org/patch/msgid/9c19a44219acd988e678cf9abe21363911184625.1497480754.git.digetx@gmail.com

diff --git a/drivers/gpu/drm/tegra/drm.c b/drivers/gpu/drm/tegra/drm.c
index fefa715c43150fe704d6260944b133a6413b43fd..81f86a67c10d28416a3fbe3d69694b8c7dfc34ee 100644 (file)
--- a/drivers/gpu/drm/tegra/drm.c
+++ b/drivers/gpu/drm/tegra/drm.c
@@ -539,7 +539,7 @@ 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;