From nobody Mon Feb 9 23:40:49 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=arm.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1624274753330874.2149748938674; Mon, 21 Jun 2021 04:25:53 -0700 (PDT) Received: from localhost ([::1]:56502 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lvI3s-0001KG-9L for importer@patchew.org; Mon, 21 Jun 2021 07:25:52 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:50588) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lvHwx-0000IA-AC for qemu-devel@nongnu.org; Mon, 21 Jun 2021 07:18:44 -0400 Received: from foss.arm.com ([217.140.110.172]:53764) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lvHwv-0001cV-54 for qemu-devel@nongnu.org; Mon, 21 Jun 2021 07:18:43 -0400 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 57D48D6E; Mon, 21 Jun 2021 04:18:39 -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 9ACAF3F718; Mon, 21 Jun 2021 04:18:36 -0700 (PDT) From: Steven Price To: Catalin Marinas , Marc Zyngier , Will Deacon Subject: [PATCH v17 4/6] KVM: arm64: Expose KVM_ARM_CAP_MTE Date: Mon, 21 Jun 2021 12:17:14 +0100 Message-Id: <20210621111716.37157-5-steven.price@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210621111716.37157-1-steven.price@arm.com> References: <20210621111716.37157-1-steven.price@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=217.140.110.172; envelope-from=steven.price@arm.com; helo=foss.arm.com X-Spam_score_int: -68 X-Spam_score: -6.9 X-Spam_bar: ------ X-Spam_report: (-6.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_HI=-5, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Peter Maydell , "Dr. David Alan Gilbert" , Andrew Jones , 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 Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" It's now safe for the VMM to enable MTE in a guest, so expose the capability to user space. Reviewed-by: Catalin Marinas Signed-off-by: Steven Price --- arch/arm64/kvm/arm.c | 9 +++++++++ arch/arm64/kvm/reset.c | 4 ++++ arch/arm64/kvm/sys_regs.c | 3 +++ 3 files changed, 16 insertions(+) diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index e720148232a0..28ce26a68f09 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -93,6 +93,12 @@ int kvm_vm_ioctl_enable_cap(struct kvm *kvm, r =3D 0; kvm->arch.return_nisv_io_abort_to_user =3D true; break; + case KVM_CAP_ARM_MTE: + if (!system_supports_mte() || kvm->created_vcpus) + return -EINVAL; + r =3D 0; + kvm->arch.mte_enabled =3D true; + break; default: r =3D -EINVAL; break; @@ -237,6 +243,9 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long = ext) */ r =3D 1; break; + case KVM_CAP_ARM_MTE: + r =3D system_supports_mte(); + break; case KVM_CAP_STEAL_TIME: r =3D kvm_arm_pvtime_supported(); break; diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c index d37ebee085cf..9e6922b9503a 100644 --- a/arch/arm64/kvm/reset.c +++ b/arch/arm64/kvm/reset.c @@ -244,6 +244,10 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu) switch (vcpu->arch.target) { default: if (test_bit(KVM_ARM_VCPU_EL1_32BIT, vcpu->arch.features)) { + if (vcpu->kvm->arch.mte_enabled) { + ret =3D -EINVAL; + goto out; + } pstate =3D VCPU_RESET_PSTATE_SVC; } else { pstate =3D VCPU_RESET_PSTATE_EL1; diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 5c75b24eae21..f6f126eb6ac1 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -1312,6 +1312,9 @@ static bool access_ccsidr(struct kvm_vcpu *vcpu, stru= ct sys_reg_params *p, static unsigned int mte_visibility(const struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd) { + if (kvm_has_mte(vcpu->kvm)) + return 0; + return REG_HIDDEN; } =20 --=20 2.20.1