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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 B2B6CC2BCA1 for ; Fri, 7 Jun 2019 12:49:23 +0000 (UTC) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) (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 90DDB208C3 for ; Fri, 7 Jun 2019 12:49:23 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 90DDB208C3 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from mail.linux-foundation.org (localhost [127.0.0.1]) by mail.linuxfoundation.org (Postfix) with ESMTP id 765EF120F; Fri, 7 Jun 2019 12:49:23 +0000 (UTC) Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 343E51209 for ; Fri, 7 Jun 2019 12:48:34 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp1.linuxfoundation.org (Postfix) with ESMTP id D278A623 for ; Fri, 7 Jun 2019 12:48:33 +0000 (UTC) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 77A82499; Fri, 7 Jun 2019 05:48:33 -0700 (PDT) Received: from [10.1.196.129] (ostrya.cambridge.arm.com [10.1.196.129]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 734AA40151; Fri, 7 Jun 2019 05:48:31 -0700 (PDT) Subject: Re: [PATCH v8 26/29] vfio-pci: Register an iommu fault handler To: Eric Auger , "eric.auger.pro@gmail.com" , "iommu@lists.linux-foundation.org" , "linux-kernel@vger.kernel.org" , "kvm@vger.kernel.org" , "kvmarm@lists.cs.columbia.edu" , "joro@8bytes.org" , "alex.williamson@redhat.com" , "jacob.jun.pan@linux.intel.com" , "yi.l.liu@intel.com" , Will Deacon , Robin Murphy References: <20190526161004.25232-1-eric.auger@redhat.com> <20190526161004.25232-27-eric.auger@redhat.com> From: Jean-Philippe Brucker Message-ID: <63b37149-1f74-bca1-35ea-5e849c0c2bbb@arm.com> Date: Fri, 7 Jun 2019 13:48:07 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.0 MIME-Version: 1.0 In-Reply-To: <20190526161004.25232-27-eric.auger@redhat.com> Content-Language: en-US Cc: Marc Zyngier , "peter.maydell@linaro.org" , "kevin.tian@intel.com" , Vincent Stehle , "ashok.raj@intel.com" X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: iommu-bounces@lists.linux-foundation.org Errors-To: iommu-bounces@lists.linux-foundation.org On 26/05/2019 17:10, Eric Auger wrote: > +int vfio_pci_iommu_dev_fault_handler(struct iommu_fault_event *evt, void *data) > +{ > + struct vfio_pci_device *vdev = (struct vfio_pci_device *) data; > + struct vfio_region_fault_prod *prod_region = > + (struct vfio_region_fault_prod *)vdev->fault_pages; > + struct vfio_region_fault_cons *cons_region = > + (struct vfio_region_fault_cons *)(vdev->fault_pages + 2 * PAGE_SIZE); > + struct iommu_fault *new = > + (struct iommu_fault *)(vdev->fault_pages + prod_region->offset + > + prod_region->prod * prod_region->entry_size); > + int prod, cons, size; > + > + mutex_lock(&vdev->fault_queue_lock); > + > + if (!vdev->fault_abi) > + goto unlock; > + > + prod = prod_region->prod; > + cons = cons_region->cons; > + size = prod_region->nb_entries; > + > + if (CIRC_SPACE(prod, cons, size) < 1) > + goto unlock; > + > + *new = evt->fault; Could you check fault.type and return an error if it's not UNRECOV here? If the fault is recoverable (very unlikely since the PRI capability is disabled, but allowed) and we return an error here, then the caller takes care of completing the fault. If we forward it to the guest instead, the producer will wait indefinitely for a response. Thanks, Jean > + prod = (prod + 1) % size; > + prod_region->prod = prod; > + mutex_unlock(&vdev->fault_queue_lock); > + > + mutex_lock(&vdev->igate); > + if (vdev->dma_fault_trigger) > + eventfd_signal(vdev->dma_fault_trigger, 1); > + mutex_unlock(&vdev->igate); > + return 0; > + > +unlock: > + mutex_unlock(&vdev->fault_queue_lock); > + return -EINVAL; > +} _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu