Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754718Ab2JFIn2 (ORCPT ); Sat, 6 Oct 2012 04:43:28 -0400 Received: from mga11.intel.com ([192.55.52.93]:34107 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753970Ab2JFInP (ORCPT ); Sat, 6 Oct 2012 04:43:15 -0400 Message-Id: X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.80,543,1344236400"; d="scan'208";a="230678806" From: Chris Wilson Subject: Re: 3.5 regression on i915 To: Willy Tarreau Cc: Daniel Vetter , linux-kernel@vger.kernel.org, Dave Airlie In-Reply-To: <20121006082016.GA22618@1wt.eu> References: <20121005234218.GC21163@1wt.eu> <20121006082016.GA22618@1wt.eu> Date: Sat, 06 Oct 2012 09:43:08 +0100 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1505 Lines: 34 On Sat, 6 Oct 2012 10:20:16 +0200, Willy Tarreau wrote: > Hi Chris, > > On Sat, Oct 06, 2012 at 09:04:34AM +0100, Chris Wilson wrote: > > > The crash happens here in i915_gem_entervt_ioctl() : > > > > > > 3659 BUG_ON(!list_empty(&dev_priv->mm.active_list)); > > > 3660 BUG_ON(!list_empty(&dev_priv->mm.flushing_list)); > > > -> 3661 BUG_ON(!list_empty(&dev_priv->mm.inactive_list)); > > > 3662 mutex_unlock(&dev->struct_mutex); > > > > That BUG_ON there is silly and can simply be removed. The check is to > > verify that no batches were submitted to the kernel whilst the UMS/GEM > > client was suspended - to which the BUG_ONs are a crude approximation. > > Furthermore, the checks are too late, since it means we attempted to > > program the hardware whilst it was in an invalid state, the BUG_ONs are > > the least of your concerns at that point. > > Excellent, that fixed it ! X still segfaults when KMS is used, but > I expect more of a pure user-space issue here since there is nothing > in dmesg. > > Would some of you accept the following patch and tag it for -stable ? Reviewed-by: Chris Wilson -Chris -- Chris Wilson, Intel Open Source Technology Centre -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/