On Fri, Sep 20, 2013 at 3:56 PM, Dave Jones davej@redhat.com wrote:
This code appears to be calling psb_gtt_free_range twice with the same args. (The second call didn't appear in the diff output, it's right after the mutex_unlock)
Spotted with Coverity, not tested due to lack of hardware.
Signed-off-by: Dave Jones davej@fedoraproject.org
diff --git a/drivers/gpu/drm/gma500/framebuffer.c b/drivers/gpu/drm/gma500/framebuffer.c index 01dd7d2..d35ffc4 100644 --- a/drivers/gpu/drm/gma500/framebuffer.c +++ b/drivers/gpu/drm/gma500/framebuffer.c @@ -479,9 +479,7 @@ static int psbfb_create(struct psb_fbdev *fbdev, mutex_unlock(&dev->struct_mutex); return 0; out_unref:
if (backing->stolen)psb_gtt_free_range(dev, backing);else
if (!backing->stolen) drm_gem_object_unreference(&backing->gem);out_err1: mutex_unlock(&dev->struct_mutex);
Hi Dave, thanks for the patch.
This part of the code is a ref count disaster and probably needs to be reworked anyways. It would be nice to always let drm_gem_object_unreference() do the final cleanup call to psb_gtt_free_range() but stolen memory is treated as an exception in some cases. Also we don't seem to take down the framebuffer correctly on failure after drm_framebuffer_init() which seems scary. psb_framebuffer_init() calls drm_framebuffer_init() which clearly states that we need to be done with the setup and stop failing at this point.
Also, we always get a stolen memory backed object (we're even lowering the depth to make sure we get one) so the drm_gem_object_unreference() is a NOP.
Anyways, your patch looks good but I would like to look at this some more since it seems broken anyways.
Patrik