From patchwork Fri Sep 4 16:00:18 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Price X-Patchwork-Id: 11757991 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 6C56192C for ; Fri, 4 Sep 2020 16:01:42 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 1F2FA2074D for ; Fri, 4 Sep 2020 16:01:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="CGhg6Yww" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1F2FA2074D 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-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.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=opmpRQuc+PKYwdlMnufzxKwYHzBZzPy5XM3TVzb2UYE=; b=CGhg6Yww1cFON8l5uctn3zA2k U2yWs8aWvXT3ZJxkePLs69Eo76q5S5w+7VnHeqkl3eRnk8pAwMA5TmXssgrpCdaJvgZdf41S9tl6b 8BkfoQ9/dPFN5qPCaiRmLBYFc6p9U/ySgBBbf6dvHktOgfoC7k6jVCcjhtoUOBS9O44aqfMfwdN2P CoDbJb4OuhHbeqAVftMdbQKQ45TXgDcVpOa0mgCzR06MbK4MDq89LlNg1REUnO86k9W8U0Yyumx8N JvRqKn1fpb+w8ODtsXkR0UUtkDtYwjdWT5i8yWr0cnl/hlDG/GxYw1uuMqcEEbBX3KLWqAzF4zoRE 9ckY91KBQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kEE9W-0003oR-0N; Fri, 04 Sep 2020 16:01:26 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kEE8f-0003Ro-JN for linux-arm-kernel@lists.infradead.org; Fri, 04 Sep 2020 16:00:48 +0000 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 6D3C313D5; Fri, 4 Sep 2020 09:00:32 -0700 (PDT) Received: from e112269-lin.arm.com (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 0724E3F66F; Fri, 4 Sep 2020 09:00:29 -0700 (PDT) From: Steven Price To: Catalin Marinas , Marc Zyngier , Will Deacon Subject: [PATCH v2 2/2] arm64: kvm: Introduce MTE VCPU feature Date: Fri, 4 Sep 2020 17:00:18 +0100 Message-Id: <20200904160018.29481-3-steven.price@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200904160018.29481-1-steven.price@arm.com> References: <20200904160018.29481-1-steven.price@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200904_120033_764779_D3689B6A X-CRM114-Status: GOOD ( 20.55 ) X-Spam-Score: -2.3 (--) X-Spam-Report: SpamAssassin version 3.4.4 on merlin.infradead.org summary: Content analysis details: (-2.3 points) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at https://www.dnswl.org/, medium trust [217.140.110.172 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , "Dr. David Alan Gilbert" , Peter Maydell , Haibo Xu , Suzuki K Poulose , qemu-devel@nongnu.org, Dave Martin , Juan Quintela , Richard Henderson , linux-kernel@vger.kernel.org, Steven Price , James Morse , Julien Thierry , Thomas Gleixner , kvmarm@lists.cs.columbia.edu, 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 Add a new VCPU features 'KVM_ARM_VCPU_MTE' which enables memory tagging on a VCPU. When enabled on any VCPU in the virtual machine this causes all pages that are faulted into the VM to have the PG_mte_tagged flag set (and the tag storage cleared if this is the first use). Signed-off-by: Steven Price --- arch/arm64/include/asm/kvm_emulate.h | 3 +++ arch/arm64/include/asm/kvm_host.h | 5 ++++- arch/arm64/include/uapi/asm/kvm.h | 1 + arch/arm64/kvm/mmu.c | 15 +++++++++++++++ arch/arm64/kvm/reset.c | 8 ++++++++ arch/arm64/kvm/sys_regs.c | 6 +++++- 6 files changed, 36 insertions(+), 2 deletions(-) diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h index 49a55be2b9a2..0042323a4b7f 100644 --- a/arch/arm64/include/asm/kvm_emulate.h +++ b/arch/arm64/include/asm/kvm_emulate.h @@ -79,6 +79,9 @@ static inline void vcpu_reset_hcr(struct kvm_vcpu *vcpu) if (cpus_have_const_cap(ARM64_MISMATCHED_CACHE_TYPE) || vcpu_el1_is_32bit(vcpu)) vcpu->arch.hcr_el2 |= HCR_TID2; + + if (test_bit(KVM_ARM_VCPU_MTE, vcpu->arch.features)) + vcpu->arch.hcr_el2 |= HCR_ATA; } static inline unsigned long *vcpu_hcr(struct kvm_vcpu *vcpu) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 4f4360dd149e..b1190366242b 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -37,7 +37,7 @@ #define KVM_MAX_VCPUS VGIC_V3_MAX_CPUS -#define KVM_VCPU_MAX_FEATURES 7 +#define KVM_VCPU_MAX_FEATURES 8 #define KVM_REQ_SLEEP \ KVM_ARCH_REQ_FLAGS(0, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP) @@ -110,6 +110,9 @@ struct kvm_arch { * supported. */ bool return_nisv_io_abort_to_user; + + /* If any VCPU has MTE enabled then all memory must be MTE enabled */ + bool vcpu_has_mte; }; struct kvm_vcpu_fault_info { diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index ba85bb23f060..2677e1ab8c16 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -106,6 +106,7 @@ struct kvm_regs { #define KVM_ARM_VCPU_SVE 4 /* enable SVE for this CPU */ #define KVM_ARM_VCPU_PTRAUTH_ADDRESS 5 /* VCPU uses address authentication */ #define KVM_ARM_VCPU_PTRAUTH_GENERIC 6 /* VCPU uses generic authentication */ +#define KVM_ARM_VCPU_MTE 7 /* VCPU supports Memory Tagging */ struct kvm_vcpu_init { __u32 target; diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index ba00bcc0c884..e8891bacd76f 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1949,6 +1949,21 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, if (vma_pagesize == PAGE_SIZE && !force_pte) vma_pagesize = transparent_hugepage_adjust(memslot, hva, &pfn, &fault_ipa); + if (system_supports_mte() && kvm->arch.vcpu_has_mte && pfn_valid(pfn)) { + /* + * VM will be able to see the page's tags, so we must ensure + * they have been initialised. + */ + struct page *page = pfn_to_page(pfn); + long i, nr_pages = compound_nr(page); + + /* if PG_mte_tagged is set, tags have already been initialised */ + for (i = 0; i < nr_pages; i++, page++) { + if (!test_and_set_bit(PG_mte_tagged, &page->flags)) + mte_clear_page_tags(page_address(page)); + } + } + if (writable) kvm_set_pfn_dirty(pfn); diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c index ee33875c5c2a..82f3883d717f 100644 --- a/arch/arm64/kvm/reset.c +++ b/arch/arm64/kvm/reset.c @@ -274,6 +274,14 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu) } } + if (test_bit(KVM_ARM_VCPU_MTE, vcpu->arch.features)) { + if (!system_supports_mte()) { + ret = -EINVAL; + goto out; + } + vcpu->kvm->arch.vcpu_has_mte = true; + } + switch (vcpu->arch.target) { default: if (test_bit(KVM_ARM_VCPU_EL1_32BIT, vcpu->arch.features)) { diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index a655f172b5ad..6a971b201e81 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -1132,7 +1132,8 @@ static u64 read_id_reg(const struct kvm_vcpu *vcpu, val &= ~(0xfUL << ID_AA64PFR0_SVE_SHIFT); val &= ~(0xfUL << ID_AA64PFR0_AMU_SHIFT); } else if (id == SYS_ID_AA64PFR1_EL1) { - val &= ~(0xfUL << ID_AA64PFR1_MTE_SHIFT); + if (!test_bit(KVM_ARM_VCPU_MTE, vcpu->arch.features)) + val &= ~(0xfUL << ID_AA64PFR1_MTE_SHIFT); } else if (id == SYS_ID_AA64ISAR1_EL1 && !vcpu_has_ptrauth(vcpu)) { val &= ~((0xfUL << ID_AA64ISAR1_APA_SHIFT) | (0xfUL << ID_AA64ISAR1_API_SHIFT) | @@ -1394,6 +1395,9 @@ static bool access_mte_regs(struct kvm_vcpu *vcpu, struct sys_reg_params *p, static unsigned int mte_visibility(const struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd) { + if (test_bit(KVM_ARM_VCPU_MTE, vcpu->arch.features)) + return 0; + return REG_HIDDEN_USER | REG_HIDDEN_GUEST; }