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authorArnd Bergmann <arnd@arndb.de>2016-10-18 00:13:39 +0200
committerDaniel Vetter <daniel.vetter@ffwll.ch>2016-10-18 09:45:17 +0200
commitcff52e5fc4cfc978b7df898dc14a0492c7ef0ae8 (patch)
treefd16fb42a9d3e98483b65b14d6f127d47d1a66c0 /drivers/gpu/drm/drm_irq.c
parentdrm: Add API for capturing frame CRCs (diff)
downloadlinux-cff52e5fc4cfc978b7df898dc14a0492c7ef0ae8.tar.xz
linux-cff52e5fc4cfc978b7df898dc14a0492c7ef0ae8.zip
drm: avoid uninitialized timestamp use in wait_vblank
gcc warns about the timestamp in drm_wait_vblank being possibly used without an initialization: drivers/gpu/drm/drm_irq.c: In function 'drm_crtc_send_vblank_event': drivers/gpu/drm/drm_irq.c:992:24: error: 'now.tv_usec' may be used uninitialized in this function [-Werror=maybe-uninitialized] drivers/gpu/drm/drm_irq.c:1069:17: note: 'now.tv_usec' was declared here drivers/gpu/drm/drm_irq.c:991:23: error: 'now.tv_sec' may be used uninitialized in this function [-Werror=maybe-uninitialized] This can happen if drm_vblank_count_and_time() returns 0 in its error path. To sanitize the error case, I'm changing that function to return a zero timestamp when it fails. Fixes: e6ae8687a87b ("drm: idiot-proof vblank") Reviewed-by: David Herrmann <dh.herrmann@gmail.com> Cc: Rob Clark <robdclark@gmail.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Mario Kleiner <mario.kleiner.de@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/20161017221355.1861551-6-arnd@arndb.de
Diffstat (limited to 'drivers/gpu/drm/drm_irq.c')
-rw-r--r--drivers/gpu/drm/drm_irq.c4
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index b969a64a1514..48a6167f5e7b 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -952,8 +952,10 @@ static u32 drm_vblank_count_and_time(struct drm_device *dev, unsigned int pipe,
u32 vblank_count;
unsigned int seq;
- if (WARN_ON(pipe >= dev->num_crtcs))
+ if (WARN_ON(pipe >= dev->num_crtcs)) {
+ *vblanktime = (struct timeval) { 0 };
return 0;
+ }
do {
seq = read_seqbegin(&vblank->seqlock);