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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 C04F3C04EB9 for ; Wed, 5 Dec 2018 10:47:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 85E6C20659 for ; Wed, 5 Dec 2018 10:47:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 85E6C20659 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727251AbeLEKrO (ORCPT ); Wed, 5 Dec 2018 05:47:14 -0500 Received: from foss.arm.com ([217.140.101.70]:51610 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726944AbeLEKrO (ORCPT ); Wed, 5 Dec 2018 05:47:14 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 9D9BE80D; Wed, 5 Dec 2018 02:47:13 -0800 (PST) Received: from [10.1.196.93] (en101.cambridge.arm.com [10.1.196.93]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 20FFC3F575; Wed, 5 Dec 2018 02:47:11 -0800 (PST) Subject: Re: [PATCH v9 2/8] KVM: arm/arm64: Re-factor setting the Stage 2 entry to exec on fault To: Anshuman Khandual , Punit Agrawal , kvmarm@lists.cs.columbia.edu Cc: marc.zyngier@arm.com, will.deacon@arm.com, linux-kernel@vger.kernel.org, Christoffer Dall , punitagrawal@gmail.com, linux-arm-kernel@lists.infradead.org References: <20181031175745.18650-1-punit.agrawal@arm.com> <20181031175745.18650-3-punit.agrawal@arm.com> <12212830-ffc6-a0e0-5de6-3e6a15ed7141@arm.com> From: Suzuki K Poulose Message-ID: Date: Wed, 5 Dec 2018 10:47:10 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: <12212830-ffc6-a0e0-5de6-3e6a15ed7141@arm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/12/2018 13:32, Anshuman Khandual wrote: > > > On 10/31/2018 11:27 PM, Punit Agrawal wrote: >> Stage 2 fault handler marks a page as executable if it is handling an >> execution fault or if it was a permission fault in which case the >> executable bit needs to be preserved. >> >> The logic to decide if the page should be marked executable is >> duplicated for PMD and PTE entries. To avoid creating another copy >> when support for PUD hugepages is introduced refactor the code to >> share the checks needed to mark a page table entry as executable. >> >> Signed-off-by: Punit Agrawal >> Reviewed-by: Suzuki K Poulose >> Cc: Christoffer Dall >> Cc: Marc Zyngier >> --- >> virt/kvm/arm/mmu.c | 28 +++++++++++++++------------- >> 1 file changed, 15 insertions(+), 13 deletions(-) >> >> diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c >> index 59595207c5e1..6912529946fb 100644 >> --- a/virt/kvm/arm/mmu.c >> +++ b/virt/kvm/arm/mmu.c >> @@ -1475,7 +1475,8 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, >> unsigned long fault_status) >> { >> int ret; >> - bool write_fault, exec_fault, writable, force_pte = false; >> + bool write_fault, writable, force_pte = false; >> + bool exec_fault, needs_exec; > > New line not required, still within 80 characters. > >> unsigned long mmu_seq; >> gfn_t gfn = fault_ipa >> PAGE_SHIFT; >> struct kvm *kvm = vcpu->kvm; >> @@ -1598,19 +1599,25 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, >> if (exec_fault) >> invalidate_icache_guest_page(pfn, vma_pagesize); >> >> + /* >> + * If we took an execution fault we have made the >> + * icache/dcache coherent above and should now let the s2 > > Coherent or invalidated with invalidate_icache_guest_page ? We also do clean_dcache above if needed. So that makes sure the data is coherent. Am I missing something here ? > >> + * mapping be executable. >> + * >> + * Write faults (!exec_fault && FSC_PERM) are orthogonal to >> + * execute permissions, and we preserve whatever we have. >> + */ > > Otherwise looks good. > Suzuki