From patchwork Wed Oct 31 17:57:42 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Punit Agrawal X-Patchwork-Id: 10663099 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 7C5A93E9D for ; Wed, 31 Oct 2018 18:00:06 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6C2E32B4E5 for ; Wed, 31 Oct 2018 18:00:06 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 604872B4E4; Wed, 31 Oct 2018 18:00:06 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 1F1722B4E5 for ; Wed, 31 Oct 2018 18:00:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=dHZ3q39N/SyfOeSRNlSzC3lce4qkyAkrVO1UZy+mhxk=; b=qyDHS/EkWK8AlF ZxjC+KdLrFLPyKmWBa8V6oSba1PMF5c06BK/LqPCqGYKkERZ2WjQp5AGbB+dOp51O9tn28zrpDISI 2aHVXzG21l5xO1xZYgh00YuxDTD2A54T5FYuxRs3oHV11/Efnppi+Crx9lQzrKSjGLobM/IlsJwEZ SL2dMd7nDXM3vGBmbADIMxQJoJNSKu3wgL0gKdYbyGXEHURwSHPW6kWYEmNNgWUmrpY7IVmTSC3+8 FzrOffOJO8aV/VsK1hWuVE2nuGEg2zxzd87RMs1JmN5XKPSWYWSYT5AtnwpkPBFMGn5Yb4f1HptHW X5mr9jTjpFef1cyhQImA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gHumc-0006Ks-HI; Wed, 31 Oct 2018 17:59:58 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gHulX-0005Kk-G5 for linux-arm-kernel@lists.infradead.org; Wed, 31 Oct 2018 17:58:58 +0000 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 AB23880D; Wed, 31 Oct 2018 10:58:40 -0700 (PDT) Received: from localhost (e105922-lin.cambridge.arm.com [10.1.197.25]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id EA3483F6A8; Wed, 31 Oct 2018 10:58:39 -0700 (PDT) From: Punit Agrawal To: kvmarm@lists.cs.columbia.edu Subject: [PATCH v9 5/8] KVM: arm64: Support PUD hugepage in stage2_is_exec() Date: Wed, 31 Oct 2018 17:57:42 +0000 Message-Id: <20181031175745.18650-6-punit.agrawal@arm.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181031175745.18650-1-punit.agrawal@arm.com> References: <20181031175745.18650-1-punit.agrawal@arm.com> MIME-Version: 1.0 X-ARM-No-Footer: FoSSMail X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181031_105851_878009_32F62156 X-CRM114-Status: GOOD ( 15.55 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: suzuki.poulose@arm.com, marc.zyngier@arm.com, Catalin Marinas , Punit Agrawal , will.deacon@arm.com, linux-kernel@vger.kernel.org, Christoffer Dall , punitagrawal@gmail.com, Russell King , linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP 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 37bf85d39607..839a619873d3 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 8da6d1b2a196..c755b37b3f92 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 1d7d8da2ef9b..336e24cddc87 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 1c669c3c1208..8e44dccd1b47 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,