[PATCH] video/fbdev: Warn when we try to free a registered framebuffer

Chris Wilson
2018-09-03T16:53:38Z

Just a tool for CI to emit the stacktrace of who is lost track of their
framebuffers and tried to free it before unregistering it.

References: https://bugs.freedesktop.org/show_bug.cgi?id=107712
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
---
Would be useful to keep in core-for-CI as a debug aide.
---
drivers/video/fbdev/core/fbsysfs.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/video/fbdev/core/fbsysfs.c b/drivers/video/fbdev/core/fbsysfs.c
index e31a182b42bf..de3afba984c7 100644
--- a/drivers/video/fbdev/core/fbsysfs.c
+++ b/drivers/video/fbdev/core/fbsysfs.c
@@ -83,6 +83,11 @@ void framebuffer_release(struct fb_info *info)
{
if (!info)
return;
+
+ if (WARN(atomic_read(&info->count),
+ "framebuffer is still registered, leaking fb_info!\n"))
+ return;
+
kfree(info->apertures);
kfree(info);
}
--
2.19.0.rc1