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=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 3E131C10F27 for ; Mon, 9 Mar 2020 17:40:06 +0000 (UTC) Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B4FEC21927 for ; Mon, 9 Mar 2020 17:40:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alsa-project.org header.i=@alsa-project.org header.b="O7Sr2DwT" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B4FEC21927 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=alsa-devel-bounces@alsa-project.org Received: from alsa1.perex.cz (alsa1.perex.cz [207.180.221.201]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa0.perex.cz (Postfix) with ESMTPS id 1CD7D16AE; Mon, 9 Mar 2020 18:39:14 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz 1CD7D16AE DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1583775604; bh=x95hiN7AoVyeQYkeI9AS7l8A+EGs9LHurtxuD+nT4vU=; h=Subject:To:References:From:Date:In-Reply-To:Cc:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=O7Sr2DwTRsLaNvosHdWb6VjuvHwTFLr/IqAwTLIWRI+mJXIrJihk4FVHs/Pzpks4y EPTEpYrDVPvhYYNbtrMo4CRqyFWNgHHo5FUCoTamvVawxVZZPpSNhovvpH9W9Mtwco idgxmym7CahLfuEr7qW/Ba2nhp4kJ3e4kVqsIN6M= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id 1BE87F8028C; Mon, 9 Mar 2020 18:39:01 +0100 (CET) Received: by alsa1.perex.cz (Postfix, from userid 50401) id EC400F8028D; Mon, 9 Mar 2020 18:38:58 +0100 (CET) Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id 3BFF0F80260 for ; Mon, 9 Mar 2020 18:38:54 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz 3BFF0F80260 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 09 Mar 2020 10:38:52 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,534,1574150400"; d="scan'208";a="231008955" Received: from crojewsk-mobl1.ger.corp.intel.com (HELO [10.252.15.110]) ([10.252.15.110]) by orsmga007.jf.intel.com with ESMTP; 09 Mar 2020 10:38:50 -0700 Subject: Re: [PATCH 4/7] ASoC: Intel: Skylake: Shield against no-NHLT configurations To: Pierre-Louis Bossart , alsa-devel@alsa-project.org References: <20200305145314.32579-1-cezary.rojewski@intel.com> <20200305145314.32579-5-cezary.rojewski@intel.com> <7f74b049-4659-9656-4396-3c1b42d2e32c@linux.intel.com> <2a380994-a723-ea25-7feb-6a650a3889e3@intel.com> From: Cezary Rojewski Message-ID: <740bc65e-afe9-cefe-4a31-d19cc9d83c56@intel.com> Date: Mon, 9 Mar 2020 18:38:48 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Cc: vkoul@kernel.org, broonie@kernel.org, tiwai@suse.com, lgirdwood@gmail.com X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" On 2020-03-09 18:01, Pierre-Louis Bossart wrote: > On 3/9/20 8:03 AM, Cezary Rojewski wrote: >> On 2020-03-06 22:03, Pierre-Louis Bossart wrote: >>> >>> >>>> -    intel_nhlt_free(skl->nhlt); >>>> +    if (skl->nhlt) >>>> +        intel_nhlt_free(skl->nhlt); >>> >>> we could alternatively move the test in intel_nhlt_free, which seems >>> like a more robust thing to do? >> >> Depends. In general kernel-internal API trusts its caller and >> appending 'ifs' everywhere would unnecessarily slow entire kernel >> down. While intel_nhlt_free is called rarely, I'd still argue caller >> should be sane about its invocation. >> >> 'if' in skl_probe could be avoided had the function's structure been >> better. 'if' in skl_remove is just fine, though. >> >> Let's leave it as is. > > it's also used in SOF: > > sound/soc/sof/intel/hda.c:              intel_nhlt_free(nhlt); > > that's why I suggested to factor the test so that both users don't need > to add the if. I understand, and my explanation still applies. SOF's intel_nhlt_free usage is great example actually. Caller is sane about its doings as it should be. Internal API needs not to suffer from callers irresponsibility. PCM does not call ::free() if ::open() fails, same as device-driver model does not care about ::remove() if ::probe() fails. Czarek