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=-4.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 B4AABC433DB for ; Mon, 25 Jan 2021 15:48:00 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 602C92224C for ; Mon, 25 Jan 2021 15:48:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 602C92224C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=pxadTU3ZuYQAOJHshvcZih9YM9XmhUSxP4Qwl35BPXE=; b=G30j+mxXU1La9fShU6bb66ire naMfdh+ynayrYUg83elk5dequFPA5PaRdLeVCk5d8sdxAhIxijQU7WYgx01etm0S0OvVWl8Q3kLHA TR9OBtVK29+LSC3jvuZHrM1kHTZUpZEVh2vHtE6iZ7LGIJjymyiQ4h1LMOsmzMn6U9uma2pUln4qj KH2HHsFGBP+0bL/WvdTvzT0NMGIcvza1CrPLVO+2JUa/5KgiMR3s0QEqgfaNcMxc7bIbL/gmhBjDI sy5mN6RsW4jluGnvWQ6MB/KVfzBqO0e13n4Jb88uN1ViVUNp9Sz2wBKSyrhvT8IIQLO7RE/AhCyrN TpJh5hpIA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l444k-0006Gw-Sf; Mon, 25 Jan 2021 15:46:46 +0000 Received: from mail-wr1-x42b.google.com ([2a00:1450:4864:20::42b]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1l444h-0006GP-Uh for linux-arm-kernel@lists.infradead.org; Mon, 25 Jan 2021 15:46:45 +0000 Received: by mail-wr1-x42b.google.com with SMTP id l12so13142320wry.2 for ; Mon, 25 Jan 2021 07:46:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=saz5MoILAriaGIGWK/aPOZ/clAw3tEuyZYXwjAIF/h4=; b=VS0BjJtjbfWaablRqn0zungdUl/9sUQPgs1HlDBWPi/HhTcQ4V51xv8PhvyQejN99w 9+mbU0x0Qz+97ncS/+vVjyrbn/4XWyOiMKPd2aNQfYjA61s+wW2L4hJRM/rEYtkixRAW UpGDFehmsrz1n/f0ETRjIa/AWnp1vtB06TppHxksWw2dgieejtP2x4iUDSoKDxPShB1Z rUUw/zsO6H8E7MUcG2DwcvzrOZG7MUeim0tqlTSehE0ykcFGNnqWEMk1u0k6Drb3JDGd 1b0fLWtIkFTSeGvMJRM9A3NKbaxGWmGfXiOKFDSip0LbsPEw4F6/E70ADOp1++04L6iw KrOw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=saz5MoILAriaGIGWK/aPOZ/clAw3tEuyZYXwjAIF/h4=; b=IAhqV0COa5JxoFMXHlZV8/pUKojac8J32FzgZiP3Ey2iOUnsS5eiPbJTGsjfa7cnqA x6rt70tB6JfBcZo28AJSFefVKSLgAXanAwtqe4U1Fc4Et6naMSnKi8EdpXYkqTVvRnW2 vxITOrZ89Ch/pazz4gqU2s04teQ0/TFKdQOtxmPazzmKmhN5y/bxJuDB1BZkmBr2kA8+ xP58297s6UsvYlgkcMGsgorEwbDAoNrCWHFAGGg4u/rdY7oMwIplEW0Q1b7beM3nO9Hh 8YudTMBPEykx6SapaOIhBzNN8/YCB7EfVfuksoIFQoi5+iQQtcVUpdsT7k5YGoK2nJug fb6Q== X-Gm-Message-State: AOAM532lHsnRNKNOtJJXFrKjP9N87Nayd3OmA3eryUk9vK2yIxbewiYZ 8Hoct6GvmJ8vhJ52KI5iVobb9A== X-Google-Smtp-Source: ABdhPJzQ1UgRTJEpMAarcXiQ9ehSoyIIoc9yIqhQjtx7Ga46cwKGEdr4iKFHuMclmoLDLgZQw0k+ZA== X-Received: by 2002:adf:dfce:: with SMTP id q14mr1302807wrn.133.1611589602413; Mon, 25 Jan 2021 07:46:42 -0800 (PST) Received: from myrica ([2001:1715:4e26:a7e0:116c:c27a:3e7f:5eaf]) by smtp.gmail.com with ESMTPSA id r1sm23377838wrl.95.2021.01.25.07.46.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 25 Jan 2021 07:46:41 -0800 (PST) Date: Mon, 25 Jan 2021 16:46:22 +0100 From: Jean-Philippe Brucker To: Jonathan Cameron Subject: Re: [PATCH v11 10/10] iommu/arm-smmu-v3: Add stall support for platform devices Message-ID: References: <20210125110650.3232195-1-jean-philippe@linaro.org> <20210125110650.3232195-11-jean-philippe@linaro.org> <20210125135009.00003ca3@Huawei.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210125135009.00003ca3@Huawei.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210125_104644_300431_BFAD6E62 X-CRM114-Status: GOOD ( 19.66 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: vivek.gautam@arm.com, guohanjun@huawei.com, will@kernel.org, lorenzo.pieralisi@arm.com, joro@8bytes.org, linux-acpi@vger.kernel.org, zhangfei.gao@linaro.org, lenb@kernel.org, devicetree@vger.kernel.org, kevin.tian@intel.com, jacob.jun.pan@linux.intel.com, eric.auger@redhat.com, robh+dt@kernel.org, linux-arm-kernel@lists.infradead.org, rjw@rjwysocki.net, shameerali.kolothum.thodi@huawei.com, iommu@lists.linux-foundation.org, sudeep.holla@arm.com, robin.murphy@arm.com, linux-accelerators@lists.ozlabs.org, baolu.lu@linux.intel.com Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Jan 25, 2021 at 01:50:09PM +0000, Jonathan Cameron wrote: > > +static int arm_smmu_master_sva_enable_iopf(struct arm_smmu_master *master) > > +{ > > + int ret; > > + struct device *dev = master->dev; > > + > > + /* > > + * Drivers for devices supporting PRI or stall should enable IOPF first. > > + * Others have device-specific fault handlers and don't need IOPF. > > + */ > > + if (!arm_smmu_master_iopf_supported(master)) > > So if we have master->iopf_enabled and this happens. Then I'm not totally sure > what prevents the disable below running its cleanup on stuff that was never > configured. Since arm_smmu_dev_enable_feature() checks that the feature is supported, iopf_enabled can only be true if arm_smmu_master_iopf_supported() is true. What's missing is checking that drivers don't disable IOPF while SVA is enabled - or else the disable below can leak. Another thing I broke in v10 :/ Thanks, Jean > > > + return 0; > > + > > + if (!master->iopf_enabled) > > + return -EINVAL; > > + > > + ret = iopf_queue_add_device(master->smmu->evtq.iopf, dev); > > + if (ret) > > + return ret; > > + > > + ret = iommu_register_device_fault_handler(dev, iommu_queue_iopf, dev); > > + if (ret) { > > + iopf_queue_remove_device(master->smmu->evtq.iopf, dev); > > + return ret; > > + } > > + return 0; > > +} > > + > > +static void arm_smmu_master_sva_disable_iopf(struct arm_smmu_master *master) > > +{ > > + struct device *dev = master->dev; > > + > > + if (!master->iopf_enabled) > > + return; > > As above, I think you need a sanity check on > > !arm_smmu_master_iopf_supported(master) before clearing the following. > > I may well be missing something that stops us getting here though. > > Alternative is probably to sanity check iopf_enabled = true is supported > before letting a driver set it. > > > > + > > + iommu_unregister_device_fault_handler(dev); > > + iopf_queue_remove_device(master->smmu->evtq.iopf, dev); > > +} _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel