From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.9]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A3D55111BE for ; Tue, 16 Jan 2024 08:15:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="E4AbxJ6k" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1705392930; x=1736928930; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=e9YbhuA296OITph7d/3ff0u8oHV/mANIphFHzWxR3q0=; b=E4AbxJ6kkc/1M5qjLJb3vvyqmnysWuJeVpQzCPgwRzmu8fUgN2nUkWb1 JBwevea9HMI+PUFXt31fXCNtwfp20ewd7XR8EC59cBDitLjWGpq47pdmX KJbOVIGkB45tZUa/O46d4Xvy5MNZ74hm2gxIdHTRsy5UXYyXOae08qmgX wiZXW1Qy/dmpuz2FwcgNVo4l8HTIsRugJyID/mlj2o84yUN/VT9pg9jjl S2+/oa5yxY9TyonoMok4lWtFYgMS8nLo2HfFtcRn4Jt1OuWUnDvxBZEDh dx5BT8CoOQT+6jR4+lp4MuVFPstqb40lIZGLkNGXx5gLyxcc0t8d7IgGs w==; X-IronPort-AV: E=McAfee;i="6600,9927,10954"; a="18387498" X-IronPort-AV: E=Sophos;i="6.04,198,1695711600"; d="scan'208";a="18387498" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orvoesa101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Jan 2024 00:15:29 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10954"; a="733529450" X-IronPort-AV: E=Sophos;i="6.04,198,1695711600"; d="scan'208";a="733529450" Received: from unknown (HELO [10.237.72.158]) ([10.237.72.158]) by orsmga003.jf.intel.com with ESMTP; 16 Jan 2024 00:15:26 -0800 Message-ID: Date: Tue, 16 Jan 2024 10:15:25 +0200 Precedence: bulk X-Mailing-List: linux-i2c@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] i2c: designware: Revert recent changes to i2c_dw_probe_lock_support() To: Kim Phillips , linux-i2c@vger.kernel.org Cc: Wolfram Sang , Andy Shevchenko , Mika Westerberg , Jan Dabros , Andi Shyti , Borislav Petkov , V Narasimhan References: <20240111125658.921083-1-jarkko.nikula@linux.intel.com> <9bb96130-d662-4904-9e4b-6a823b51a990@linux.intel.com> <614a9b32-d6e9-4506-a7a0-164954badffe@amd.com> <00f98ff9-ce2f-4edd-b4e4-a17e1a0170cd@amd.com> Content-Language: en-US From: Jarkko Nikula In-Reply-To: <00f98ff9-ce2f-4edd-b4e4-a17e1a0170cd@amd.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 1/16/24 00:44, Kim Phillips wrote: > On 1/15/24 3:16 PM, Kim Phillips wrote: >> On 1/12/24 2:13 AM, Jarkko Nikula wrote: >>> On 1/11/24 19:56, Kim Phillips wrote: >>>>> [    6.245173] i2c_designware AMDI0010:00: Unknown Synopsys >>>>> component type: 0xffffffff >>> >>> This has puzzled me all the time since I'm unable to see which one of >>> Andy's patches could cause it. However controller is clearly powered >>> down since DW_IC_COMP_TYPE register reads 0xffffffff. > > Just FYI, that message is apparently 'normal' as, e.g., a stable v6.4 > based tree emits it, but it doesn't crash because of it: > Ah, makes sense. I understood from Narasimhan's earlier mail vanilla doesn't show it and that made me confused. > So I just tested checking out bd466a892612, and indeed it produces > the stacktrace.  Prior to that commit is v6.7-rc3, which boots fine. > So right now I'm suspecting bd466a892612 is to blame for the stacktrace. > This also makes most sense to me and was my first guess. I let Andy to look at more deeply does my speculation about runtime PM being active in parallel with post probe code since before his commit driver disabled the runtime PM before returning from probe. Now if after that commit oops doesn't occur always it will easily misguide in bisecting and can lead to random results. Those are very hard to track sometimes. Good that you found this issue very immediately when code went to linux-next!