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=-5.3 required=3.0 tests=BAYES_00, 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 8F7B7C43331 for ; Wed, 3 Mar 2021 19:11:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 67DB560295 for ; Wed, 3 Mar 2021 19:11:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350010AbhCCS1i (ORCPT ); Wed, 3 Mar 2021 13:27:38 -0500 Received: from mga01.intel.com ([192.55.52.88]:33426 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1451163AbhCCGBA (ORCPT ); Wed, 3 Mar 2021 01:01:00 -0500 IronPort-SDR: TjJEI59cqI/jo6Sggtd68K09zMhHPI7Zkd4/VQJrAS7mCLiDk8GnSGMSYY2uMVDR22YFccebjr CSyLu4FL1zPw== X-IronPort-AV: E=McAfee;i="6000,8403,9911"; a="206791061" X-IronPort-AV: E=Sophos;i="5.81,219,1610438400"; d="scan'208";a="206791061" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Mar 2021 21:57:29 -0800 IronPort-SDR: R62d52h746g5jdI/PQNmcxq5OSTnWJB+uv/9hPrMByomQh5KxmP10wVscZDChXanwcANWupg5v nKj4lGouhEoQ== X-IronPort-AV: E=Sophos;i="5.81,219,1610438400"; d="scan'208";a="367485784" Received: from otc-nc-03.jf.intel.com (HELO otc-nc-03) ([10.54.39.36]) by orsmga003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Mar 2021 21:57:29 -0800 Date: Tue, 2 Mar 2021 21:57:27 -0800 From: "Raj, Ashok" To: Jean-Philippe Brucker Cc: joro@8bytes.org, will@kernel.org, vivek.gautam@arm.com, guohanjun@huawei.com, zhukeqian1@huawei.com, wangzhou1@hisilicon.com, 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, vdumpa@nvidia.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, Ashok Raj Subject: Re: [PATCH v13 06/10] iommu: Add a page fault handler Message-ID: <20210303055727.GF1914@otc-nc-03> References: <20210302092644.2553014-1-jean-philippe@linaro.org> <20210302092644.2553014-7-jean-philippe@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210302092644.2553014-7-jean-philippe@linaro.org> User-Agent: Mutt/1.5.24 (2015-08-30) Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Tue, Mar 02, 2021 at 10:26:42AM +0100, Jean-Philippe Brucker wrote: [snip] > + > +static enum iommu_page_response_code > +iopf_handle_single(struct iopf_fault *iopf) > +{ > + vm_fault_t ret; > + struct mm_struct *mm; > + struct vm_area_struct *vma; > + unsigned int access_flags = 0; > + unsigned int fault_flags = FAULT_FLAG_REMOTE; > + struct iommu_fault_page_request *prm = &iopf->fault.prm; > + enum iommu_page_response_code status = IOMMU_PAGE_RESP_INVALID; > + > + if (!(prm->flags & IOMMU_FAULT_PAGE_REQUEST_PASID_VALID)) > + return status; > + > + mm = iommu_sva_find(prm->pasid); > + if (IS_ERR_OR_NULL(mm)) > + return status; > + > + mmap_read_lock(mm); > + > + vma = find_extend_vma(mm, prm->addr); > + if (!vma) > + /* Unmapped area */ > + goto out_put_mm; > + > + if (prm->perm & IOMMU_FAULT_PERM_READ) > + access_flags |= VM_READ; > + > + if (prm->perm & IOMMU_FAULT_PERM_WRITE) { > + access_flags |= VM_WRITE; > + fault_flags |= FAULT_FLAG_WRITE; > + } > + > + if (prm->perm & IOMMU_FAULT_PERM_EXEC) { > + access_flags |= VM_EXEC; > + fault_flags |= FAULT_FLAG_INSTRUCTION; > + } > + > + if (!(prm->perm & IOMMU_FAULT_PERM_PRIV)) > + fault_flags |= FAULT_FLAG_USER; > + > + if (access_flags & ~vma->vm_flags) > + /* Access fault */ > + goto out_put_mm; > + > + ret = handle_mm_fault(vma, prm->addr, fault_flags, NULL); Should we add a trace similar to trace_page_fault_user() or kernel in arch/x86/kernel/mm/fault.c or maybe add a perf_sw_event() for device faults? Cheers, Ashok