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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 7ACADC54EE9 for ; Fri, 16 Sep 2022 10:56:44 +0000 (UTC) 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 E06AD1740; Fri, 16 Sep 2022 12:55:51 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz E06AD1740 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1663325802; bh=fJFUW8+1F9qiAKmSsj0VidfyYyZ0hwH8viyxweFmXBk=; h=Date:Subject:To:References:From:In-Reply-To:Cc:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=omtny1axZWPy8W7HhlDYIskFCBESCku1xIQW5tkNvap6+PqAD6UWzbIlFlGCMDZkJ x2CUShkMf7l0jDlV4MXXpZTyf2M89zfR8meDtRmdkCyR6Mb9wIw4KyZNf6LvqO2lb7 977KazlIespu/B57NGrDRq0KpjuTAxPeX3zbb8PQ= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id 6E94FF80254; Fri, 16 Sep 2022 12:55:51 +0200 (CEST) Received: by alsa1.perex.cz (Postfix, from userid 50401) id E3355F802BE; Fri, 16 Sep 2022 12:55:49 +0200 (CEST) Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) (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 6AF14F800E5 for ; Fri, 16 Sep 2022 12:55:42 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz 6AF14F800E5 Authentication-Results: alsa1.perex.cz; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="M28QIdsq" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1663325744; x=1694861744; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=fJFUW8+1F9qiAKmSsj0VidfyYyZ0hwH8viyxweFmXBk=; b=M28QIdsqpBGyrw2BrQtBhH/MS8qKga+yl4Jpb4J+lqNf/Ctm9Vc/Q5C/ zsV8H+jdEmIEfOwaQXbDBaDG1hkJjfne0nn3hfyMMhCQDuENHa226TF2d RkK9wHzZeNxsoYAwJp78smFnh7Jw0O5TqbH2trY9i2tDTw7QiYmaIR3eN ZVrzRb9sgM2C8b21bT/3d9OOa4EGN95dQm7IAIhZPZ6A/aJnO4vv6iK2X Nv/lSpWij+9CuqKbsyURIDxaS8ZbTvwxSRV1Rj17Z2okvYhz7v2Q3UWoe mVEMGqR2NCNUgF/bsKU+6lFPkSrdChuBPK5ZE1414/mQaS6BiPl/4Ql9O g==; X-IronPort-AV: E=McAfee;i="6500,9779,10471"; a="279348822" X-IronPort-AV: E=Sophos;i="5.93,320,1654585200"; d="scan'208";a="279348822" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Sep 2022 03:55:38 -0700 X-IronPort-AV: E=Sophos;i="5.93,320,1654585200"; d="scan'208";a="743298468" Received: from kchan21-mobl1.ger.corp.intel.com (HELO [10.252.61.56]) ([10.252.61.56]) by orsmga004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Sep 2022 03:55:35 -0700 Message-ID: <0f4154f6-ad5a-22e7-3b95-5a577c1dff47@linux.intel.com> Date: Fri, 16 Sep 2022 12:55:31 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Firefox/91.0 Thunderbird/91.11.0 Subject: Re: [PATCH] soundwire: cadence: Don't overwrite msg->buf during write commands Content-Language: en-US To: Richard Fitzgerald , vkoul@kernel.org, yung-chuan.liao@linux.intel.com, sanyog.r.kale@intel.com References: <20220916103505.1562210-1-rf@opensource.cirrus.com> From: Pierre-Louis Bossart In-Reply-To: <20220916103505.1562210-1-rf@opensource.cirrus.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: patches@opensource.cirrus.com, alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org 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 9/16/22 12:35, Richard Fitzgerald wrote: > The buf passed in struct sdw_msg must only be written for a READ, > in that case the RDATA part of the response is the data value of the > register. > > For a write command there is no RDATA, and buf should be assumed to > be const and unmodifable. The original caller should not expect its data > buffer to be corrupted by an sdw_nwrite(). > > Signed-off-by: Richard Fitzgerald Reviewed-by: Pierre-Louis Bossart > --- > drivers/soundwire/cadence_master.c | 9 ++++++--- > 1 file changed, 6 insertions(+), 3 deletions(-) > > diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c > index be9cd47f31ec..3ef472049980 100644 > --- a/drivers/soundwire/cadence_master.c > +++ b/drivers/soundwire/cadence_master.c > @@ -544,9 +544,12 @@ cdns_fill_msg_resp(struct sdw_cdns *cdns, > return SDW_CMD_IGNORED; > } > > - /* fill response */ > - for (i = 0; i < count; i++) > - msg->buf[i + offset] = FIELD_GET(CDNS_MCP_RESP_RDATA, cdns->response_buf[i]); > + if (msg->flags == SDW_MSG_FLAG_READ) { > + /* fill response */ > + for (i = 0; i < count; i++) > + msg->buf[i + offset] = FIELD_GET(CDNS_MCP_RESP_RDATA, > + cdns->response_buf[i]); > + } > > return SDW_CMD_OK; > }