Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753865AbaAGUMY (ORCPT ); Tue, 7 Jan 2014 15:12:24 -0500 Received: from mail-ie0-f171.google.com ([209.85.223.171]:53004 "EHLO mail-ie0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753480AbaAGUMR (ORCPT ); Tue, 7 Jan 2014 15:12:17 -0500 MIME-Version: 1.0 X-Originating-IP: [178.83.130.250] In-Reply-To: References: Date: Tue, 7 Jan 2014 21:12:16 +0100 Message-ID: Subject: Re: Excessive WARN()s in Intel 915 driver From: Daniel Vetter To: Alan Stern Cc: intel-gfx , Kernel development list Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jan 7, 2014 at 7:50 PM, Alan Stern wrote: > After all, it's not like there's anything I can do to fix the hardware, > is there? And it doesn't look like the pipe state mismatch is going to > go away by itself. Or is this a genuine, fixable, software bug? These are genuine software bugs - every time one of these WARNs fires our software tracking and the actual hardware state have diverged, which eventually will lead to really subtle and hard to reproduce bugs. > In any case, wouldn't it be good enough for this message to be > dev_warn() instead of WARN()? I really want users to report these issues, and excessive WARNs seems to be the only way to get those reports. Please boot with drm.debug=0xe added to your kernel cmdline and reproduce this issues. Also, which precise kernel are you running? Testing latest -rc is always recommended, this state checker code is fairly new and gets constantly extended and bugs fixed ... Yours, Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - 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/