drm/vgem: Remember to offset relative timeouts to mod_timer() by jiffies

mod_timer() takes an absolute jiffie value, not a relative timeout and
quietly fixup the missed ret=0 otherwise gcc just always returns that
the fence timed out.

Testcase: igt/vgem_basic/fence
Fixes: 407779848445 ("drm/vgem: Attach sw fences to exported vGEM dma-buf")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1468834278-26716-1-git-send-email-chris@chris-wilson.co.uk

diff --git a/drivers/gpu/drm/vgem/vgem_fence.c b/drivers/gpu/drm/vgem/vgem_fence.c
index e77b522..892417b 100644 (file)
--- a/drivers/gpu/drm/vgem/vgem_fence.c
+++ b/drivers/gpu/drm/vgem/vgem_fence.c
@@ -107,7 +107,7 @@ static struct fence *vgem_fence_create(struct vgem_file *vfile,
        setup_timer(&fence->timer, vgem_fence_timeout, (unsigned long)fence);
 
        /* We force the fence to expire within 10s to prevent driver hangs */
-       mod_timer(&fence->timer, VGEM_FENCE_TIMEOUT);
+       mod_timer(&fence->timer, jiffies + VGEM_FENCE_TIMEOUT);
 
        return &fence->base;
 }
@@ -240,7 +240,7 @@ int vgem_fence_signal_ioctl(struct drm_device *dev,
        struct vgem_file *vfile = file->driver_priv;
        struct drm_vgem_fence_signal *arg = data;
        struct fence *fence;
-       int ret;
+       int ret = 0;
 
        if (arg->flags)
                return -EINVAL;