[PATCH 4.20 083/111] gpu/drm: Fix lock held when returning to user space.
From: Greg Kroah-Hartman
Date: Mon Jan 21 2019 - 08:49:53 EST
4.20-stable review patch. If anyone has any objections, please let me know.
------------------
From: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
commit 4089e272ac61603931beb024d4d640de2cb390e0 upstream.
We need to call drm_modeset_acquire_fini() when drm_atomic_state_alloc()
failed or call drm_modeset_acquire_init() after drm_atomic_state_alloc()
succeeded.
Signed-off-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
Reported-by: syzbot <syzbot+6ea337c427f5083ebdf2@xxxxxxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/1547115571-21219-1-git-send-email-penguin-kernel@xxxxxxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/drm_atomic_uapi.c | 3 +--
drivers/gpu/drm/drm_mode_object.c | 4 ++--
2 files changed, 3 insertions(+), 4 deletions(-)
--- a/drivers/gpu/drm/drm_atomic_uapi.c
+++ b/drivers/gpu/drm/drm_atomic_uapi.c
@@ -1275,12 +1275,11 @@ int drm_mode_atomic_ioctl(struct drm_dev
(arg->flags & DRM_MODE_PAGE_FLIP_EVENT))
return -EINVAL;
- drm_modeset_acquire_init(&ctx, DRM_MODESET_ACQUIRE_INTERRUPTIBLE);
-
state = drm_atomic_state_alloc(dev);
if (!state)
return -ENOMEM;
+ drm_modeset_acquire_init(&ctx, DRM_MODESET_ACQUIRE_INTERRUPTIBLE);
state->acquire_ctx = &ctx;
state->allow_modeset = !!(arg->flags & DRM_MODE_ATOMIC_ALLOW_MODESET);
--- a/drivers/gpu/drm/drm_mode_object.c
+++ b/drivers/gpu/drm/drm_mode_object.c
@@ -458,11 +458,11 @@ static int set_property_atomic(struct dr
struct drm_modeset_acquire_ctx ctx;
int ret;
- drm_modeset_acquire_init(&ctx, 0);
-
state = drm_atomic_state_alloc(dev);
if (!state)
return -ENOMEM;
+
+ drm_modeset_acquire_init(&ctx, 0);
state->acquire_ctx = &ctx;
retry:
if (prop == state->dev->mode_config.dpms_property) {