From:   Suzuki K Poulose <suzuki.poulose@arm.com>
To:     kvm@vger.kernel.org, kvmarm@lists.linux.dev
Cc:     suzuki.poulose@arm.com,
        Alexandru Elisei <alexandru.elisei@arm.com>,
        Andrew Jones <andrew.jones@linux.dev>,
        Christoffer Dall <christoffer.dall@arm.com>,
        Fuad Tabba <tabba@google.com>,
        Jean-Philippe Brucker <jean-philippe@linaro.org>,
        Joey Gouly <Joey.Gouly@arm.com>, Marc Zyngier <maz@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Oliver Upton <oliver.upton@linux.dev>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Quentin Perret <qperret@google.com>,
        Steven Price <steven.price@arm.com>,
        Thomas Huth <thuth@redhat.com>, Will Deacon <will@kernel.org>,
        Zenghui Yu <yuzenghui@huawei.com>, linux-coco@lists.linux.dev,
        kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org
Subject: [RFC kvmtool 01/31] arm64: Disable MTE when CFI flash is emulated
Date:   Fri, 27 Jan 2023 11:39:02 +0000
Message-Id: <20230127113932.166089-2-suzuki.poulose@arm.com>
In-Reply-To: <20230127113932.166089-1-suzuki.poulose@arm.com>
References: <20230127112248.136810-1-suzuki.poulose@arm.com>
 <20230127113932.166089-1-suzuki.poulose@arm.com>
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CFI Flash file image cannot be mapped into the memory of the
guest if MTE is enabled. Thus disable MTE if flash emulation
is requested.

Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
---
 arm/aarch64/kvm.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arm/aarch64/kvm.c b/arm/aarch64/kvm.c
index 54200c9e..5a53badb 100644
--- a/arm/aarch64/kvm.c
+++ b/arm/aarch64/kvm.c
@@ -145,6 +145,12 @@ void kvm__arch_enable_mte(struct kvm *kvm)
 		return;
 	}
 
+	if (kvm->cfg.flash_filename) {
+		kvm->cfg.arch.mte_disabled = true;
+		pr_info("MTE is incompatible with CFI flash support, disabling");
+		return;
+	}
+
 	if (kvm->cfg.arch.mte_disabled) {
 		pr_debug("MTE disabled by user");
 		return;
-- 
2.34.1