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 EA4E3C433EF for ; Thu, 16 Jun 2022 02:10:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347950AbiFPCKb (ORCPT ); Wed, 15 Jun 2022 22:10:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46824 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1358443AbiFPCKW (ORCPT ); Wed, 15 Jun 2022 22:10:22 -0400 Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 291035AEE0; Wed, 15 Jun 2022 19:10:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1655345406; x=1686881406; h=message-id:date:mime-version:cc:subject:to:references: from:in-reply-to:content-transfer-encoding; bh=u/polTrCcfTR/bnfvj7XjWWQORpzgrJJNnRIhd6+LYo=; b=Qu0Y5FW9OsO/xe+YNrKgzUBvvWAG7ijn3jZtuJVzH2cpylwiwtv+ZnVk 1dxCADEwAAzOkRiBfPi/0XDlXEs46ozk6JSWvtHlifRy0VbkWA0AqvGFc Eoybia42yGBAKe+tZ2ubI1FD4lY9lvvaNnKZPPGhQ7KJBOIt9+o/c0WHc y8Ly5SYJ1BEvXXReFGqOgTmS2bl9e9zRMgOJ1dmyn/Chxkjulhblz4yKj CQfWX3SOqbhNcGUdGoToD0Y75DUe0QKiI27n2pSkLUn1AeNtFZFFQ/WVl 6udazhGJM6w92GkaYjQ13D5cwlxnHDxZBEbCSjODowSl8ouomWKN1d7yB g==; X-IronPort-AV: E=McAfee;i="6400,9594,10379"; a="258999490" X-IronPort-AV: E=Sophos;i="5.91,302,1647327600"; d="scan'208";a="258999490" Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Jun 2022 19:09:59 -0700 X-IronPort-AV: E=Sophos;i="5.91,302,1647327600"; d="scan'208";a="831355596" Received: from yuefengs-mobl.ccr.corp.intel.com (HELO [10.255.30.105]) ([10.255.30.105]) by fmsmga006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Jun 2022 19:09:51 -0700 Message-ID: <0c0e6ec8-725d-93e8-44f1-db6c8a673a97@linux.intel.com> Date: Thu, 16 Jun 2022 10:09:49 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.9.1 Cc: baolu.lu@linux.intel.com, suravee.suthikulpanit@amd.com, alyssa@rosenzweig.io, dwmw2@infradead.org, yong.wu@mediatek.com, mjrosato@linux.ibm.com, gerald.schaefer@linux.ibm.com, thierry.reding@gmail.com, vdumpa@nvidia.com, jonathanh@nvidia.com, cohuck@redhat.com, thunder.leizhen@huawei.com, tglx@linutronix.de, christophe.jaillet@wanadoo.fr, john.garry@huawei.com, chenxiang66@hisilicon.com, saiprakash.ranjan@codeaurora.org, isaacm@codeaurora.org, yangyingliang@huawei.com, jordan@cosmicpenguin.net, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-s390@vger.kernel.org, linux-tegra@vger.kernel.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org Subject: Re: [PATCH v2 1/5] iommu: Return -EMEDIUMTYPE for incompatible domain and device/group Content-Language: en-US To: Nicolin Chen , joro@8bytes.org, will@kernel.org, marcan@marcan.st, sven@svenpeter.dev, robin.murphy@arm.com, robdclark@gmail.com, matthias.bgg@gmail.com, orsonzhai@gmail.com, baolin.wang7@gmail.com, zhang.lyra@gmail.com, jean-philippe@linaro.org, alex.williamson@redhat.com, jgg@nvidia.com, kevin.tian@intel.com References: <20220616000304.23890-1-nicolinc@nvidia.com> <20220616000304.23890-2-nicolinc@nvidia.com> From: Baolu Lu In-Reply-To: <20220616000304.23890-2-nicolinc@nvidia.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On 2022/6/16 08:03, Nicolin Chen wrote: > diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c > index 44016594831d..0dd13330fe12 100644 > --- a/drivers/iommu/intel/iommu.c > +++ b/drivers/iommu/intel/iommu.c > @@ -4323,7 +4323,7 @@ static int prepare_domain_attach_device(struct iommu_domain *domain, > return -ENODEV; > > if (dmar_domain->force_snooping && !ecap_sc_support(iommu->ecap)) > - return -EOPNOTSUPP; > + return -EMEDIUMTYPE; > > /* check if this iommu agaw is sufficient for max mapped address */ > addr_width = agaw_to_width(iommu->agaw); > @@ -4331,10 +4331,10 @@ static int prepare_domain_attach_device(struct iommu_domain *domain, > addr_width = cap_mgaw(iommu->cap); > > if (dmar_domain->max_addr > (1LL << addr_width)) { > - dev_err(dev, "%s: iommu width (%d) is not " > + dev_dbg(dev, "%s: iommu width (%d) is not " > "sufficient for the mapped address (%llx)\n", > __func__, addr_width, dmar_domain->max_addr); > - return -EFAULT; > + return -EMEDIUMTYPE; > } > dmar_domain->gaw = addr_width; Can we simply remove the dev_err()? As the return value has explicitly explained the failure reason, putting a print statement won't help much. Best regards, baolu 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 smtp2.osuosl.org (smtp2.osuosl.org [140.211.166.133]) (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 CC9D4C43334 for ; Thu, 16 Jun 2022 02:10:13 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id 6DC7840C83; Thu, 16 Jun 2022 02:10:13 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp2.osuosl.org ([127.0.0.1]) by localhost (smtp2.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id H8xvo7lHkB6I; Thu, 16 Jun 2022 02:10:12 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [IPv6:2605:bc80:3010:104::8cd3:938]) by smtp2.osuosl.org (Postfix) with ESMTPS id 4ADDD4031D; Thu, 16 Jun 2022 02:10:12 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 13D61C0039; 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15 Jun 2022 19:09:51 -0700 Message-ID: <0c0e6ec8-725d-93e8-44f1-db6c8a673a97@linux.intel.com> Date: Thu, 16 Jun 2022 10:09:49 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.9.1 Subject: Re: [PATCH v2 1/5] iommu: Return -EMEDIUMTYPE for incompatible domain and device/group Content-Language: en-US To: Nicolin Chen , joro@8bytes.org, will@kernel.org, marcan@marcan.st, sven@svenpeter.dev, robin.murphy@arm.com, robdclark@gmail.com, matthias.bgg@gmail.com, orsonzhai@gmail.com, baolin.wang7@gmail.com, zhang.lyra@gmail.com, jean-philippe@linaro.org, alex.williamson@redhat.com, jgg@nvidia.com, kevin.tian@intel.com References: <20220616000304.23890-1-nicolinc@nvidia.com> <20220616000304.23890-2-nicolinc@nvidia.com> From: Baolu Lu In-Reply-To: <20220616000304.23890-2-nicolinc@nvidia.com> Cc: jordan@cosmicpenguin.net, thierry.reding@gmail.com, alyssa@rosenzweig.io, linux-s390@vger.kernel.org, saiprakash.ranjan@codeaurora.org, kvm@vger.kernel.org, jonathanh@nvidia.com, linux-arm-kernel@lists.infradead.org, yangyingliang@huawei.com, gerald.schaefer@linux.ibm.com, linux-arm-msm@vger.kernel.org, christophe.jaillet@wanadoo.fr, linux-tegra@vger.kernel.org, tglx@linutronix.de, virtualization@lists.linux-foundation.org, isaacm@codeaurora.org, cohuck@redhat.com, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, linux-mediatek@lists.infradead.org, dwmw2@infradead.org X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On 2022/6/16 08:03, Nicolin Chen wrote: > diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c > index 44016594831d..0dd13330fe12 100644 > --- a/drivers/iommu/intel/iommu.c > +++ b/drivers/iommu/intel/iommu.c > @@ -4323,7 +4323,7 @@ static int prepare_domain_attach_device(struct iommu_domain *domain, > return -ENODEV; > > if (dmar_domain->force_snooping && !ecap_sc_support(iommu->ecap)) > - return -EOPNOTSUPP; > + return -EMEDIUMTYPE; > > /* check if this iommu agaw is sufficient for max mapped address */ > addr_width = agaw_to_width(iommu->agaw); > @@ -4331,10 +4331,10 @@ static int prepare_domain_attach_device(struct iommu_domain *domain, > addr_width = cap_mgaw(iommu->cap); > > if (dmar_domain->max_addr > (1LL << addr_width)) { > - dev_err(dev, "%s: iommu width (%d) is not " > + dev_dbg(dev, "%s: iommu width (%d) is not " > "sufficient for the mapped address (%llx)\n", > __func__, addr_width, dmar_domain->max_addr); > - return -EFAULT; > + return -EMEDIUMTYPE; > } > dmar_domain->gaw = addr_width; Can we simply remove the dev_err()? As the return value has explicitly explained the failure reason, putting a print statement won't help much. Best regards, baolu _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 C1368C43334 for ; Thu, 16 Jun 2022 02:11:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: Content-Transfer-Encoding:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:From:References:To:Subject:MIME-Version: Date:Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; 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Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.9.1 Subject: Re: [PATCH v2 1/5] iommu: Return -EMEDIUMTYPE for incompatible domain and device/group Content-Language: en-US To: Nicolin Chen , joro@8bytes.org, will@kernel.org, marcan@marcan.st, sven@svenpeter.dev, robin.murphy@arm.com, robdclark@gmail.com, matthias.bgg@gmail.com, orsonzhai@gmail.com, baolin.wang7@gmail.com, zhang.lyra@gmail.com, jean-philippe@linaro.org, alex.williamson@redhat.com, jgg@nvidia.com, kevin.tian@intel.com References: <20220616000304.23890-1-nicolinc@nvidia.com> <20220616000304.23890-2-nicolinc@nvidia.com> From: Baolu Lu In-Reply-To: <20220616000304.23890-2-nicolinc@nvidia.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220615_191003_964844_8BD6662E X-CRM114-Status: GOOD ( 10.94 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mjrosato@linux.ibm.com, jordan@cosmicpenguin.net, thierry.reding@gmail.com, alyssa@rosenzweig.io, linux-s390@vger.kernel.org, saiprakash.ranjan@codeaurora.org, kvm@vger.kernel.org, jonathanh@nvidia.com, linux-arm-kernel@lists.infradead.org, yangyingliang@huawei.com, gerald.schaefer@linux.ibm.com, linux-arm-msm@vger.kernel.org, john.garry@huawei.com, christophe.jaillet@wanadoo.fr, thunder.leizhen@huawei.com, linux-tegra@vger.kernel.org, tglx@linutronix.de, virtualization@lists.linux-foundation.org, yong.wu@mediatek.com, isaacm@codeaurora.org, chenxiang66@hisilicon.com, cohuck@redhat.com, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, suravee.suthikulpanit@amd.com, linux-mediatek@lists.infradead.org, dwmw2@infradead.org, baolu.lu@linux.intel.com Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 2022/6/16 08:03, Nicolin Chen wrote: > diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c > index 44016594831d..0dd13330fe12 100644 > --- a/drivers/iommu/intel/iommu.c > +++ b/drivers/iommu/intel/iommu.c > @@ -4323,7 +4323,7 @@ static int prepare_domain_attach_device(struct iommu_domain *domain, > return -ENODEV; > > if (dmar_domain->force_snooping && !ecap_sc_support(iommu->ecap)) > - return -EOPNOTSUPP; > + return -EMEDIUMTYPE; > > /* check if this iommu agaw is sufficient for max mapped address */ > addr_width = agaw_to_width(iommu->agaw); > @@ -4331,10 +4331,10 @@ static int prepare_domain_attach_device(struct iommu_domain *domain, > addr_width = cap_mgaw(iommu->cap); > > if (dmar_domain->max_addr > (1LL << addr_width)) { > - dev_err(dev, "%s: iommu width (%d) is not " > + dev_dbg(dev, "%s: iommu width (%d) is not " > "sufficient for the mapped address (%llx)\n", > __func__, addr_width, dmar_domain->max_addr); > - return -EFAULT; > + return -EMEDIUMTYPE; > } > dmar_domain->gaw = addr_width; Can we simply remove the dev_err()? As the return value has explicitly explained the failure reason, putting a print statement won't help much. Best regards, baolu _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel