From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Wilson Subject: Re: [PATCH 4/5] drm/i915: Remove the deferred-free list Date: Tue, 20 Mar 2012 13:59:19 +0000 Message-ID: References: <1330118022-5701-1-git-send-email-chris@chris-wilson.co.uk> <1330118022-5701-5-git-send-email-chris@chris-wilson.co.uk> <20120320133851.GA27231@phenom.ffwll.local> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by gabe.freedesktop.org (Postfix) with ESMTP id B368E9F01C for ; Tue, 20 Mar 2012 06:59:24 -0700 (PDT) In-Reply-To: <20120320133851.GA27231@phenom.ffwll.local> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org To: Daniel Vetter Cc: intel-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org On Tue, 20 Mar 2012 14:38:51 +0100, Daniel Vetter wrote: > On Fri, Feb 24, 2012 at 09:30:33PM +0000, Chris Wilson wrote: > I haven't looked much at the patch, but the deferred-free looks more bogus > the more I stare at it. As long as an object is active, we /should/ have a > reference on it, so we should never fail to wait for outstanding rendering > on the final free. The only execption is the ilk/vt-d unbind w/a, but that > one is already uninterruptible. > > So I think we should just drop the deferred free list, check for any > errors from unbind with a WARN_ON and bail out (leaking the bo) in that > case. Right. I am just worried because we did have a bug with a case where it appeared that we did free an active object. I will have to dig through that and see if could be explained by some other use-after-free. -Chris -- Chris Wilson, Intel Open Source Technology Centre