From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 957CCC6778A for ; Tue, 3 Jul 2018 11:57:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 491F524C8F for ; Tue, 3 Jul 2018 11:57:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 491F524C8F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752721AbeGCL5l (ORCPT ); Tue, 3 Jul 2018 07:57:41 -0400 Received: from mga09.intel.com ([134.134.136.24]:54424 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752067AbeGCL5k (ORCPT ); Tue, 3 Jul 2018 07:57:40 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga102.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 03 Jul 2018 04:57:39 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,303,1526367600"; d="scan'208";a="69275097" Received: from jnikula-mobl2.fi.intel.com (HELO localhost) ([10.237.72.62]) by fmsmga001.fm.intel.com with ESMTP; 03 Jul 2018 04:57:23 -0700 From: Jani Nikula To: Daniel Vetter , Lyude Paul Cc: linux-fbdev@vger.kernel.org, Kees Cook , Bartlomiej Zolnierkiewicz , =?utf-8?Q?Jan_H=2E?= =?utf-8?Q?_Sch=C3=B6nherr?= , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Bjorn Helgaas Subject: Re: [PATCH] video/console/vgacon: Print big fat warning with nomodeset In-Reply-To: <20180703073452.GD7880@phenom.ffwll.local> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <20180702210442.18648-1-lyude@redhat.com> <20180703073452.GD7880@phenom.ffwll.local> Date: Tue, 03 Jul 2018 14:57:08 +0300 Message-ID: <87a7r8r0q3.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 03 Jul 2018, Daniel Vetter wrote: > On Mon, Jul 02, 2018 at 05:04:40PM -0400, Lyude Paul wrote: >> It's been a pretty good while since kernel modesetting was introduced. >> It has almost entirely replaced previous solutions which required >> userspace modesetting, and I can't even recall any drivers off the top >> of my head for modern day hardware that don't only support one or the >> other. Even nvidia's ugly blob does not require the use of nomodeset, >> and only requires that nouveau be blacklisted. >> >> Effectively, the only thing nomodeset does in the year 2018 is disable >> your graphics drivers. Since VESA is a thing, this will give many users >> the false impression that they've actually fixed an issue they were >> having with their machine simply because the laptop will boot up to a >> degraded GUI. This of course, is never actually the case. >> >> Things get even worse when you consider that there's still an enormous >> amount of tutorials users find on the internet that still suggest adding >> nomodeset, along with various users who have been around long enough to >> still suggest it. >> >> There really isn't any legitimate reason I can see for this to be an >> option that's used by anyone else other then developers, or properly >> informed users. So, let's end the confusion and start printing warnings >> whenever it's enabled. >> >> Signed-off-by: Lyude Paul > > Yeah makes tons of sense. I think we should also perhaps mark the option > as a tainting one, but I think that's only wired up for module option. You could do that by adding add_taint(TAINT_USER, LOCKDEP_STILL_OK); in text_mode(). If you do that, you should probably amend the warning message accordingly. Either way, Acked-by: Jani Nikula > Reviewed-by: Daniel Vetter > >> --- >> drivers/video/console/vgacon.c | 5 +++++ >> 1 file changed, 5 insertions(+) >> >> diff --git a/drivers/video/console/vgacon.c b/drivers/video/console/vgacon.c >> index f09e17b60e45..09731b2f6815 100644 >> --- a/drivers/video/console/vgacon.c >> +++ b/drivers/video/console/vgacon.c >> @@ -112,6 +112,11 @@ EXPORT_SYMBOL(vgacon_text_force); >> static int __init text_mode(char *str) >> { >> vgacon_text_mode_force = true; >> + >> + pr_warning("You have booted with nomodeset. This means your GPU drivers are DISABLED\n"); >> + pr_warning("Any video related functionality will be severely degraded, and you may not even be able to suspend the system properly\n"); >> + pr_warning("Unless you actually understand what nomodeset does, you should reboot without enabling it\n"); >> + >> return 1; >> } >> >> -- >> 2.17.1 >> >> _______________________________________________ >> dri-devel mailing list >> dri-devel@lists.freedesktop.org >> https://lists.freedesktop.org/mailman/listinfo/dri-devel -- Jani Nikula, Intel Open Source Graphics Center