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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9864EC64EC7 for ; Mon, 13 Feb 2023 16:43:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231179AbjBMQno (ORCPT ); Mon, 13 Feb 2023 11:43:44 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36824 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229576AbjBMQnn (ORCPT ); Mon, 13 Feb 2023 11:43:43 -0500 Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 07945DBD5 for ; Mon, 13 Feb 2023 08:43:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1676306623; x=1707842623; h=from:to:cc:subject:in-reply-to:references:date: message-id:mime-version:content-transfer-encoding; bh=0n+HIBdxHdzt277lPdNmpKc0Tu1vAbJdNbPGnkpCCNw=; b=PPyPCrgi7wjuL8rhJ8/icbAKgLDCaUKQcgzoIsFVGgXi/ve7k1dbeIy/ ytJn8RtM19yV2pqaC3JxRVEj4tknIb1ZGzZuSoAUm2KBmxJ4mPNjUv4KD RIOUUr+mzlxgIZAVkrJ5UkPXov92TqEliGFGyojzr2wVWzPTUYU4btBrJ t8j6zfE5AaNx3Aj/xhJt++LXNZ+rypdxpk11DyhuYvPuPTgAovIhLhOrr 3oBh2qKEHnJMpXVav8uxTLW8nJ45kLKTfC/eJb20PlMCNGc2jvd5/bHRq A7dRvMAHjRrZTnKx8mupnTT7AOhnBDrmkxZoMQqWn9EwrUfkm3iz7dw68 Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10620"; a="318953356" X-IronPort-AV: E=Sophos;i="5.97,294,1669104000"; d="scan'208";a="318953356" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Feb 2023 08:43:42 -0800 X-IronPort-AV: E=McAfee;i="6500,9779,10620"; a="701329108" X-IronPort-AV: E=Sophos;i="5.97,294,1669104000"; d="scan'208";a="701329108" Received: from tkatila-mobl.ger.corp.intel.com (HELO localhost) ([10.252.50.147]) by orsmga001-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Feb 2023 08:43:38 -0800 From: Jani Nikula To: Greg Kroah-Hartman Cc: Daniel Vetter , Jim Cromie , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, Maxime Ripard , Thomas Zimmermann , stable@vger.kernel.org, David Airlie Subject: Re: [Intel-gfx] [PATCH] drm: Disable dynamic debug as broken In-Reply-To: <878rh5x032.fsf@intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <20230207143337.2126678-1-jani.nikula@intel.com> <878rh5x032.fsf@intel.com> Date: Mon, 13 Feb 2023 18:43:31 +0200 Message-ID: <875yc5v7m4.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Fri, 10 Feb 2023, Jani Nikula wrote: > On Tue, 07 Feb 2023, Greg Kroah-Hartman wrot= e: >> On Tue, Feb 07, 2023 at 04:33:37PM +0200, Jani Nikula wrote: >>> From: Ville Syrj=C3=A4l=C3=A4 >>>=20 >>> CONFIG_DRM_USE_DYNAMIC_DEBUG breaks debug prints for (at least modular) >>> drm drivers. The debug prints can be reinstated by manually frobbing >>> /sys/module/drm/parameters/debug after the fact, but at that point the >>> damage is done and all debugs from driver probe are lost. This makes >>> drivers totally undebuggable. >>>=20 >>> There's a more complete fix in progress [1], with further details, but >>> we need this fixed in stable kernels. Mark the feature as broken and >>> disable it by default, with hopes distros follow suit and disable it as >>> well. >>>=20 >>> [1] https://lore.kernel.org/r/20230125203743.564009-1-jim.cromie@gmail.= com >>>=20 >>> Fixes: 84ec67288c10 ("drm_print: wrap drm_*_dbg in dyndbg descriptor fa= ctory macro") >>> Cc: Jim Cromie >>> Cc: Greg Kroah-Hartman >>> Cc: Maarten Lankhorst >>> Cc: Maxime Ripard >>> Cc: Thomas Zimmermann >>> Cc: David Airlie >>> Cc: Daniel Vetter >>> Cc: dri-devel@lists.freedesktop.org >>> Cc: # v6.1+ >>> Signed-off-by: Ville Syrj=C3=A4l=C3=A4 >>> Signed-off-by: Jani Nikula >>> --- >>> drivers/gpu/drm/Kconfig | 3 ++- >>> 1 file changed, 2 insertions(+), 1 deletion(-) >>>=20 >>> diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig >>> index f42d4c6a19f2..dc0f94f02a82 100644 >>> --- a/drivers/gpu/drm/Kconfig >>> +++ b/drivers/gpu/drm/Kconfig >>> @@ -52,7 +52,8 @@ config DRM_DEBUG_MM >>>=20=20 >>> config DRM_USE_DYNAMIC_DEBUG >>> bool "use dynamic debug to implement drm.debug" >>> - default y >>> + default n >>> + depends on BROKEN >>> depends on DRM >>> depends on DYNAMIC_DEBUG || DYNAMIC_DEBUG_CORE >>> depends on JUMP_LABEL >> >> Acked-by: Greg Kroah-Hartman > > Thanks Greg, any more acks from anyone? > > Maxime, since there's going to be an -rc8, I suggest taking this via > drm-misc-fixes. Is that okay with you? (You're doing drm-misc-fixes this > round, right?) Pushed to drm-misc-fixes with Maxime's IRC ack and Jim's ack elsewhere in the thread. Thanks. BR, Jani. > > BR, > Jani. --=20 Jani Nikula, Intel Open Source Graphics Center