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=-8.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT 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 72222C43143 for ; Mon, 1 Oct 2018 15:55:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 41AE7213A2 for ; Mon, 1 Oct 2018 15:55:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 41AE7213A2 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 S1726554AbeJAWd6 (ORCPT ); Mon, 1 Oct 2018 18:33:58 -0400 Received: from foss.arm.com ([217.140.101.70]:51854 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725934AbeJAWd5 (ORCPT ); Mon, 1 Oct 2018 18:33:57 -0400 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 0EBBF1684; Mon, 1 Oct 2018 08:55:30 -0700 (PDT) Received: from localhost (e105922-lin.emea.arm.com [10.4.13.28]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 7F9773F5D3; Mon, 1 Oct 2018 08:55:29 -0700 (PDT) From: Punit Agrawal To: kvmarm@lists.cs.columbia.edu Cc: Punit Agrawal , marc.zyngier@arm.com, will.deacon@arm.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, suzuki.poulose@arm.com, Christoffer Dall , Russell King , Catalin Marinas Subject: [PATCH v8 6/9] KVM: arm64: Support PUD hugepage in stage2_is_exec() Date: Mon, 1 Oct 2018 16:54:40 +0100 Message-Id: <20181001155443.23032-7-punit.agrawal@arm.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20181001155443.23032-1-punit.agrawal@arm.com> References: <20181001155443.23032-1-punit.agrawal@arm.com> X-ARM-No-Footer: FoSSMail Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In preparation for creating PUD hugepages at stage 2, add support for detecting execute permissions on PUD page table entries. Faults due to lack of execute permissions on page table entries is used to perform i-cache invalidation on first execute. Provide trivial implementations of arm32 helpers to allow sharing of code. Signed-off-by: Punit Agrawal Reviewed-by: Suzuki K Poulose Cc: Christoffer Dall Cc: Marc Zyngier Cc: Russell King Cc: Catalin Marinas Cc: Will Deacon --- arch/arm/include/asm/kvm_mmu.h | 6 +++ arch/arm64/include/asm/kvm_mmu.h | 5 +++ arch/arm64/include/asm/pgtable-hwdef.h | 2 + virt/kvm/arm/mmu.c | 53 +++++++++++++++++++++++--- 4 files changed, 61 insertions(+), 5 deletions(-) diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h index 9ec09f4cc284..26a2ab05b3f6 100644 --- a/arch/arm/include/asm/kvm_mmu.h +++ b/arch/arm/include/asm/kvm_mmu.h @@ -102,6 +102,12 @@ static inline bool kvm_s2pud_readonly(pud_t *pud) return false; } +static inline bool kvm_s2pud_exec(pud_t *pud) +{ + BUG(); + return false; +} + static inline pte_t kvm_s2pte_mkwrite(pte_t pte) { pte_val(pte) |= L_PTE_S2_RDWR; diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h index 3cc342177474..c06ef3be8ca9 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -261,6 +261,11 @@ static inline bool kvm_s2pud_readonly(pud_t *pudp) return kvm_s2pte_readonly((pte_t *)pudp); } +static inline bool kvm_s2pud_exec(pud_t *pudp) +{ + return !(READ_ONCE(pud_val(*pudp)) & PUD_S2_XN); +} + #define hyp_pte_table_empty(ptep) kvm_page_empty(ptep) #ifdef __PAGETABLE_PMD_FOLDED diff --git a/arch/arm64/include/asm/pgtable-hwdef.h b/arch/arm64/include/asm/pgtable-hwdef.h index fd208eac9f2a..10ae592b78b8 100644 --- a/arch/arm64/include/asm/pgtable-hwdef.h +++ b/arch/arm64/include/asm/pgtable-hwdef.h @@ -193,6 +193,8 @@ #define PMD_S2_RDWR (_AT(pmdval_t, 3) << 6) /* HAP[2:1] */ #define PMD_S2_XN (_AT(pmdval_t, 2) << 53) /* XN[1:0] */ +#define PUD_S2_XN (_AT(pudval_t, 2) << 53) /* XN[1:0] */ + /* * Memory Attribute override for Stage-2 (MemAttr[3:0]) */ diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c index 9c48f2ca6583..5fd1eae7d964 100644 --- a/virt/kvm/arm/mmu.c +++ b/virt/kvm/arm/mmu.c @@ -1083,23 +1083,66 @@ static int stage2_set_pmd_huge(struct kvm *kvm, struct kvm_mmu_memory_cache return 0; } -static bool stage2_is_exec(struct kvm *kvm, phys_addr_t addr) +/* + * stage2_get_leaf_entry - walk the stage2 VM page tables and return + * true if a valid and present leaf-entry is found. A pointer to the + * leaf-entry is returned in the appropriate level variable - pudpp, + * pmdpp, ptepp. + */ +static bool stage2_get_leaf_entry(struct kvm *kvm, phys_addr_t addr, + pud_t **pudpp, pmd_t **pmdpp, pte_t **ptepp) { + pud_t *pudp; pmd_t *pmdp; pte_t *ptep; - pmdp = stage2_get_pmd(kvm, NULL, addr); + *pudpp = NULL; + *pmdpp = NULL; + *ptepp = NULL; + + pudp = stage2_get_pud(kvm, NULL, addr); + if (!pudp || stage2_pud_none(kvm, *pudp) || !stage2_pud_present(kvm, *pudp)) + return false; + + if (stage2_pud_huge(kvm, *pudp)) { + *pudpp = pudp; + return true; + } + + pmdp = stage2_pmd_offset(kvm, pudp, addr); if (!pmdp || pmd_none(*pmdp) || !pmd_present(*pmdp)) return false; - if (pmd_thp_or_huge(*pmdp)) - return kvm_s2pmd_exec(pmdp); + if (pmd_thp_or_huge(*pmdp)) { + *pmdpp = pmdp; + return true; + } ptep = pte_offset_kernel(pmdp, addr); if (!ptep || pte_none(*ptep) || !pte_present(*ptep)) return false; - return kvm_s2pte_exec(ptep); + *ptepp = ptep; + return true; +} + +static bool stage2_is_exec(struct kvm *kvm, phys_addr_t addr) +{ + pud_t *pudp; + pmd_t *pmdp; + pte_t *ptep; + bool found; + + found = stage2_get_leaf_entry(kvm, addr, &pudp, &pmdp, &ptep); + if (!found) + return false; + + if (pudp) + return kvm_s2pud_exec(pudp); + else if (pmdp) + return kvm_s2pmd_exec(pmdp); + else + return kvm_s2pte_exec(ptep); } static int stage2_set_pte(struct kvm *kvm, struct kvm_mmu_memory_cache *cache, -- 2.18.0