Date:   Wed,  8 Dec 2021 15:22:58 +0000
In-Reply-To: <20211208152300.2478542-1-qperret@google.com>
Message-Id: <20211208152300.2478542-6-qperret@google.com>
Mime-Version: 1.0
References: <20211208152300.2478542-1-qperret@google.com>
Subject: [PATCH 5/6] KVM: arm64: pkvm: Stub io map functions
From:   Quentin Perret <qperret@google.com>
To:     Marc Zyngier <maz@kernel.org>, James Morse <james.morse@arm.com>,
        Alexandru Elisei <alexandru.elisei@arm.com>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>
Cc:     linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu,
        linux-kernel@vger.kernel.org, kernel-team@android.com,
        qperret@google.com
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

Now that GICv2 is disabled in nVHE protected mode there should be no
other reason for the host to use create_hyp_io_mappings() or
kvm_phys_addr_ioremap(). Add sanity checks to make sure that assumption
remains true looking forward.

Signed-off-by: Quentin Perret <qperret@google.com>
---
 arch/arm64/kvm/mmu.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 326cdfec74a1..605c104eb030 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -407,6 +407,9 @@ int create_hyp_io_mappings(phys_addr_t phys_addr, size_t size,
 	unsigned long addr;
 	int ret;
 
+	if (is_protected_kvm_enabled())
+		return -EPERM;
+
 	*kaddr = ioremap(phys_addr, size);
 	if (!*kaddr)
 		return -ENOMEM;
@@ -650,6 +653,9 @@ 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())
+		return -EPERM;
+
 	size += offset_in_page(guest_ipa);
 	guest_ipa &= PAGE_MASK;
 
-- 
2.34.1.400.ga245620fadb-goog