From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 82DF04B7167; Thu, 24 Sep 2026 16:06:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790265980; cv=none; b=RXMeht6QmMfCIJ2iaorHCKXHkCNaUfWbd3kJLrUwfEvjYQEUupaXRNz3m8MDw36yyWmn3nAYwWGAsqnWdVFDayRzwGVH4oh0aTF6BRmfUfmAFIpldUsY5qUdja/PBeWRzL5s/cd6gzwoS5Xobcbjyy31kcZg5Sq/UDrQyeWIdYM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790265980; c=relaxed/simple; bh=aUMJm4MmfVPuRwP9cR6se83O2r8UV6BA2hVIN/OMalE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JgYbH9aPSvDCTD67UAZUwSXK7lqP1iRbSp/mTOgH+I2bRVbLyPLHQPwodpem8iAKHPdxDRA7afKjK0atEypB2IrESF3qyFIzQ/etd0v3LvKW74Kr3ynvCDNdt0IL8mLjzv14GUgTvbx96rcJkWoBel/6hBQD5e+n/J2WhY0TnlQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=ifI8ensj; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="ifI8ensj" 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 53F101E7D; Thu, 24 Sep 2026 09:06:14 -0700 (PDT) Received: from ewhatever.cambridge.arm.com (ewhatever.cambridge.arm.com [10.2.197.99]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 9EAAC3F86C; Thu, 24 Sep 2026 09:06:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1790265977; bh=aUMJm4MmfVPuRwP9cR6se83O2r8UV6BA2hVIN/OMalE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ifI8ensjRQ0Jh5Jlv4SVCgwkex5CCuJrDuIQwOvtZq11ce8a9HIBAE307eQbW/JZJ ijd1prqvCUMtGpwgSZpllG0yq2lkwZwM1HWV4QZVRiNHFlEs0mYbsdif0SEXWhbV8S NJysNL94iId7dPQv/LH+4R7bNAt4602XrvBJk0Zo= From: Suzuki K Poulose To: kvm@vger.kernel.org, kvmarm@lists.linux.dev Cc: maz@kernel.org, will@kernel.org, catalin.marinas@arm.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, steven.price@arm.com, aneesh.kumar@kernel.org, oupton@kernel.org, gshan@redhat.com, joey.gouly@arm.com, tabba@google.com, yuzenghui@huawei.com, linux-coco@lists.linux.dev, gankulkarni@os.amperecomputing.com, sdonthineni@nvidia.com, alpergun@google.com, fj0570is@fujitsu.com, WeiLin.Chang@arm.com, lpieralisi@kernel.org, enju.kohei@fujitsu.com, sudeep.holla@arm.com, jonathan.cameron@oss.qualcomm.com, Suzuki K Poulose Subject: [PATCH v20 13/22] KVM: arm64: Mandate VGIC v3 for pKVM VMs and Realms Date: Thu, 24 Sep 2026 17:04:55 +0100 Message-ID: <20260924160504.853911-14-suzuki.poulose@arm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260924160504.853911-1-suzuki.poulose@arm.com> References: <20260924160504.853911-1-suzuki.poulose@arm.com> Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit pKVM does not trust the host. Realm VMs follow a similar trust model, with the Realm Management Monitor owning the protected state instead of the host. Add a helper to identify VMs that run under a host-distrusting hypervisor. Use this for blocking ioremap of vgic-v2 into stage2 and prevent creation of VGIC other than v3. Reviewed-by: Jonathan Cameron Tested-by: Gavin Shan Signed-off-by: Suzuki K Poulose --- Changes since v18: - Cover pKVM guests for VGIC v3 mandate. - Merge the VGIC mandate check in here. --- arch/arm64/include/asm/kvm_host.h | 3 +++ arch/arm64/kvm/mmu.c | 2 +- arch/arm64/kvm/vgic/vgic-init.c | 2 ++ 3 files changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 871f503e9f164..4d75b8e6797bb 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -328,6 +328,8 @@ enum fgt_group_id { enum kvm_arm_vm_flavor { VM_NVHE, VM_VHE, + /* VMs running on a hyp that doesn't trust */ + MARKER(__VM_DISTRUSTING_HYP), VM_PKVM, /* Normal guests on pKVM */ MARKER(__VM_PROTECTED), VM_PROTECTED_PKVM, /* Protected VM */ @@ -1575,6 +1577,7 @@ struct kvm *kvm_arch_alloc_vm(void); #define kvm_vm_is_unprotected_pkvm(kvm) \ (is_protected_kvm_enabled() && ((kvm)->arch.vm_flavor == VM_PKVM)) +#define kvm_vm_hyp_is_distrusting(kvm) ((kvm)->arch.vm_flavor >= __VM_DISTRUSTING_HYP) int kvm_arm_vcpu_finalize(struct kvm_vcpu *vcpu, int feature); bool kvm_arm_vcpu_is_finalized(struct kvm_vcpu *vcpu); diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 8e092efdf0825..8f21652d3625c 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1252,7 +1252,7 @@ int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa, KVM_PGTABLE_PROT_R | (writable ? KVM_PGTABLE_PROT_W : 0); - if (is_protected_kvm_enabled()) + if (kvm_vm_hyp_is_distrusting(kvm)) return -EPERM; size += offset_in_page(guest_ipa); diff --git a/arch/arm64/kvm/vgic/vgic-init.c b/arch/arm64/kvm/vgic/vgic-init.c index 4012df6002ea6..874025513afcc 100644 --- a/arch/arm64/kvm/vgic/vgic-init.c +++ b/arch/arm64/kvm/vgic/vgic-init.c @@ -84,6 +84,8 @@ int kvm_vgic_create(struct kvm *kvm, u32 type) !kvm_vgic_global_state.can_emulate_gicv2) return -ENODEV; + if (kvm_vm_hyp_is_distrusting(kvm) && type != KVM_DEV_TYPE_ARM_VGIC_V3) + return -ENODEV; /* * Ensure mutual exclusion with vCPU creation and any vCPU ioctls by: * -- 2.43.0