Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965855AbbLPPhr (ORCPT ); Wed, 16 Dec 2015 10:37:47 -0500 Received: from mail-wm0-f45.google.com ([74.125.82.45]:35905 "EHLO mail-wm0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965797AbbLPPho (ORCPT ); Wed, 16 Dec 2015 10:37:44 -0500 Date: Wed, 16 Dec 2015 16:37:41 +0100 From: Daniel Vetter To: Dmitry Torokhov Cc: Gustavo Padovan , Greg Kroah-Hartman , devel@driverdev.osuosl.org, Andrew Bresticker , Arve =?iso-8859-1?B?SGr4bm5lduVn?= , dri-devel@lists.freedesktop.org, "linux-kernel@vger.kernel.org" , Riley Andrews , linux-media@vger.kernel.org Subject: Re: [PATCH] android: fix warning when releasing active sync point Message-ID: <20151216153740.GS30437@phenom.ffwll.local> Mail-Followup-To: Dmitry Torokhov , Gustavo Padovan , Greg Kroah-Hartman , devel@driverdev.osuosl.org, Andrew Bresticker , Arve =?iso-8859-1?B?SGr4bm5lduVn?= , dri-devel@lists.freedesktop.org, "linux-kernel@vger.kernel.org" , Riley Andrews , linux-media@vger.kernel.org References: <20151215012955.GA28277@dtor-ws> <20151215133020.GD883@joana> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Operating-System: Linux phenom 4.2.0-1-amd64 User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2505 Lines: 48 On Tue, Dec 15, 2015 at 09:22:56AM -0800, Dmitry Torokhov wrote: > On Tue, Dec 15, 2015 at 5:30 AM, Gustavo Padovan wrote: > > 2015-12-14 Dmitry Torokhov : > > > >> Userspace can close the sync device while there are still active fence > >> points, in which case kernel produces the following warning: > >> > >> [ 43.853176] ------------[ cut here ]------------ > >> [ 43.857834] WARNING: CPU: 0 PID: 892 at /mnt/host/source/src/third_party/kernel/v3.18/drivers/staging/android/sync.c:439 android_fence_release+0x88/0x104() > >> [ 43.871741] CPU: 0 PID: 892 Comm: Binder_5 Tainted: G U 3.18.0-07661-g0550ce9 #1 > >> [ 43.880176] Hardware name: Google Tegra210 Smaug Rev 1+ (DT) > >> [ 43.885834] Call trace: > >> [ 43.888294] [] dump_backtrace+0x0/0x10c > >> [ 43.893697] [] show_stack+0x10/0x1c > >> [ 43.898756] [] dump_stack+0x74/0xb8 > >> [ 43.903814] [] warn_slowpath_common+0x84/0xb0 > >> [ 43.909736] [] warn_slowpath_null+0x14/0x20 > >> [ 43.915482] [] android_fence_release+0x84/0x104 > >> [ 43.921582] [] fence_release+0x104/0x134 > >> [ 43.927066] [] sync_fence_free+0x74/0x9c > >> [ 43.932552] [] sync_fence_release+0x34/0x48 > >> [ 43.938304] [] __fput+0x100/0x1b8 > >> [ 43.943185] [] ____fput+0x8/0x14 > >> [ 43.947982] [] task_work_run+0xb0/0xe4 > >> [ 43.953297] [] do_notify_resume+0x44/0x5c > >> [ 43.958867] ---[ end trace 5a2aa4027cc5d171 ]--- > > > > This crash report seems to be for a 3.18 kernel. Can you reproduce it > > on upstream kernel as well? > > Unfortunately this board does not run upsrteam just yet, but looking > at the sync driver and fence code we are pretty much in sync with > upstream. Just to check: Is that with a proper hw driver, or using SW_SYNC? The later will get removed in upstream since it's a debug/validation only interface. Well, removed for drivers and production systems, the kselftests will use it. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch -- 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/