From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bernie Thompson Date: Mon, 28 Jun 2010 21:26:54 +0000 Subject: Re: [PATCH 4/4] HID: picolcd: implement refcounting of framebuffer Message-Id: List-Id: References: <20100628223327.23c6006a@neptune.home> In-Reply-To: <20100628223327.23c6006a@neptune.home> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To: linux-fbdev@vger.kernel.org On Mon, Jun 28, 2010 at 1:33 PM, Bruno Pr=C3=A9mont wrote: > As our device may be hot-unplugged and framebuffer cannot handle > this case by itself we need to keep track of usage count so as > to release fb_info and framebuffer memory only after the last user > has closed framebuffer. > > We need to do the freeing in a scheduled work as fb_release() > is called with fb_info lock held. The udlfb (DisplayLink) framebuffer driver just got a similar fix in the last few days: http://git.plugable.com/gitphp/index.php?p=3Dudlfb&a=3Dcommit&h=AE0502457e5= 4904b1a9e0d67db6719182824da7c The need to schedule work in fb_release() because fbmem.c touches it after release is especially unfortunate (we had to do the same). Anyone have existing thoughts about fixing the release path more centrally? Best wishes, Bernie http://plugable.com/