Hi
On Sat, Sep 3, 2016 at 7:15 PM, Noralf Trønnes noralf@tronnes.org wrote:
Den 03.09.2016 14:04, skrev Noralf Trønnes:
Den 02.09.2016 10:22, skrev David Herrmann:
Create a simple fbdev device during SimpleDRM setup so legacy user-space and fbcon can use it.
Signed-off-by: David Herrmann dh.herrmann@gmail.com
[...]
diff --git a/drivers/gpu/drm/simpledrm/simpledrm_fbdev.c b/drivers/gpu/drm/simpledrm/simpledrm_fbdev.c
[...]
+void sdrm_fbdev_bind(struct sdrm_device *sdrm) +{
- struct drm_fb_helper *fbdev;
- int r;
- fbdev = kzalloc(sizeof(*fbdev), GFP_KERNEL);
- if (!fbdev)
return;- drm_fb_helper_prepare(sdrm->ddev, fbdev, &sdrm_fbdev_funcs);
- r = drm_fb_helper_init(sdrm->ddev, fbdev, 1, 1);
- if (r < 0)
goto error;- r = drm_fb_helper_single_add_all_connectors(fbdev);
- if (r < 0)
goto error;- r = drm_fb_helper_initial_config(fbdev,
sdrm->ddev->mode_config.preferred_depth);- if (r < 0)
goto error;- if (!fbdev->fbdev)
goto error;- sdrm->fbdev = fbdev;
- return;
+error:
- drm_fb_helper_fini(fbdev);
- kfree(fbdev);
+}
+void sdrm_fbdev_unbind(struct sdrm_device *sdrm) +{
- struct drm_fb_helper *fbdev = sdrm->fbdev;
- if (!fbdev)
return;- sdrm->fbdev = NULL;
- drm_fb_helper_unregister_fbi(fbdev);
- cancel_work_sync(&fbdev->dirty_work);
- drm_fb_helper_release_fbi(fbdev);
- drm_framebuffer_unreference(fbdev->fb);
I get a warning that there are still fb's left during unbind:
[ 48.666003] WARNING: CPU: 0 PID: 716 at drivers/gpu/drm/drm_crtc.c:3855 drm_mode_config_cleanup+0x180/0x1f4 [drm]
This worked:
drm_framebuffer_unreference(fbdev->fb);
drm_framebuffer_unregister_private(fbdev->fb);drm_framebuffer_cleanup(fbdev->fb);Well not quite, this doesn't free the bo, so maybe this:
drm_framebuffer_unreference(fbdev->fb);
drm_framebuffer_unregister_private(fbdev->fb);sdrm_fb_destroy(fbdev->fb);IIRC the reason ref count doesn't drop to zero, had something to do with multiple fb_set_par calls taking reference but not being dropped later.
So I don't like this at all. If we leak references, we should fix the ref-leak or properly document why this is fine to do. Daniel, what is the exact reason we have unregister_private()? Maybe I should try and trace the ref-leak.
Thanks David