From:   Kristina Martsenko <kristina.martsenko@arm.com>
To:     linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev
Cc:     Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>, Marc Zyngier <maz@kernel.org>,
        Oliver Upton <oliver.upton@linux.dev>,
        James Morse <james.morse@arm.com>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Zenghui Yu <yuzenghui@huawei.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Mark Brown <broonie@kernel.org>,
        Luis Machado <luis.machado@arm.com>,
        Vladimir Murzin <vladimir.murzin@arm.com>,
        linux-kernel@vger.kernel.org
Subject: [PATCH 06/10] KVM: arm64: hide MOPS from guests
Date:   Thu, 16 Feb 2023 16:00:08 +0000
Message-Id: <20230216160012.272345-7-kristina.martsenko@arm.com>
In-Reply-To: <20230216160012.272345-1-kristina.martsenko@arm.com>
References: <20230216160012.272345-1-kristina.martsenko@arm.com>
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As FEAT_MOPS is not supported in guests yet, hide it from the ID
registers for guests.

The MOPS instructions are UNDEFINED in guests as HCRX_EL2.MSCEn is not
set in HCRX_GUEST_FLAGS, and will take an exception to EL1 if executed.

Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
---
 arch/arm64/kvm/sys_regs.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 0bc7df55916e..3456205c6b92 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -1213,6 +1213,7 @@ static u64 read_id_reg(const struct kvm_vcpu *vcpu, struct sys_reg_desc const *r
 				 ARM64_FEATURE_MASK(ID_AA64ISAR2_EL1_GPA3));
 		if (!cpus_have_final_cap(ARM64_HAS_WFXT))
 			val &= ~ARM64_FEATURE_MASK(ID_AA64ISAR2_EL1_WFxT);
+		val &= ~ARM64_FEATURE_MASK(ID_AA64ISAR2_EL1_MOPS);
 		break;
 	case SYS_ID_AA64DFR0_EL1:
 		/* Limit debug to ARMv8.0 */
-- 
2.25.1