On Tue, May 03, 2022 at 10:19:34PM +0200, Javier Martinez Canillas wrote: > A reference to the framebuffer device struct fb_info is stored in the file > private data, but this reference could no longer be valid and must not be > accessed directly. Instead, the file_fb_info() accessor function must be > used since it does sanity checking to make sure that the fb_info is valid. > > This can happen for example if the registered framebuffer device is for a > driver that just uses a framebuffer provided by the system firmware. In > that case, the fbdev core would unregister the framebuffer device when a > real video driver is probed and ask to remove conflicting framebuffers. > > Most fbdev file operations already use the helper to get the fb_info but > get_fb_unmapped_area() and fb_deferred_io_fsync() don't. Fix those two. > > Since fb_deferred_io_fsync() is not in fbmem.o, the helper has to be > exported. Rename it and add a fb_ prefix to denote that is public now. > > Reported-by: Junxiao Chang <junxiao.chang@xxxxxxxxx> > Signed-off-by: Javier Martinez Canillas <javierm@xxxxxxxxxx> Acked-by: Sam Ravnborg <sam@xxxxxxxxxxxx>
