From aa091898b56e1c813b1125522bd9104b5be3773d Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Wed, 26 Aug 2020 18:52:59 +0100 Subject: [PATCH] arm64: kvm: mte: Hide the MTE CPUID information from the guests KVM does not support MTE in guests yet, so clear the corresponding field in the ID_AA64PFR1_EL1 register. In addition, inject an undefined exception in the guest if it accesses one of the GCR_EL1, RGSR_EL1, TFSR_EL1 or TFSRE0_EL1 registers. While the emulate_sys_reg() function already injects an undefined exception, this patch prevents the unnecessary printk. Signed-off-by: Catalin Marinas Cc: Steven Price Acked-by: Marc Zyngier --- arch/arm64/kvm/sys_regs.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 077293b5115fa..379f4969d0bd7 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -1131,6 +1131,8 @@ static u64 read_id_reg(const struct kvm_vcpu *vcpu, if (!vcpu_has_sve(vcpu)) val &= ~(0xfUL << ID_AA64PFR0_SVE_SHIFT); val &= ~(0xfUL << ID_AA64PFR0_AMU_SHIFT); + } else if (id == SYS_ID_AA64PFR1_EL1) { + val &= ~(0xfUL << ID_AA64PFR1_MTE_SHIFT); } else if (id == SYS_ID_AA64ISAR1_EL1 && !vcpu_has_ptrauth(vcpu)) { val &= ~((0xfUL << ID_AA64ISAR1_APA_SHIFT) | (0xfUL << ID_AA64ISAR1_API_SHIFT) | @@ -1382,6 +1384,13 @@ static bool access_ccsidr(struct kvm_vcpu *vcpu, struct sys_reg_params *p, return true; } +static bool access_mte_regs(struct kvm_vcpu *vcpu, struct sys_reg_params *p, + const struct sys_reg_desc *r) +{ + kvm_inject_undefined(vcpu); + return false; +} + /* sys_reg_desc initialiser for known cpufeature ID registers */ #define ID_SANITISED(name) { \ SYS_DESC(SYS_##name), \ @@ -1547,6 +1556,10 @@ static const struct sys_reg_desc sys_reg_descs[] = { { SYS_DESC(SYS_SCTLR_EL1), access_vm_reg, reset_val, SCTLR_EL1, 0x00C50078 }, { SYS_DESC(SYS_ACTLR_EL1), access_actlr, reset_actlr, ACTLR_EL1 }, { SYS_DESC(SYS_CPACR_EL1), NULL, reset_val, CPACR_EL1, 0 }, + + { SYS_DESC(SYS_RGSR_EL1), access_mte_regs }, + { SYS_DESC(SYS_GCR_EL1), access_mte_regs }, + { SYS_DESC(SYS_ZCR_EL1), NULL, reset_val, ZCR_EL1, 0, .visibility = sve_visibility }, { SYS_DESC(SYS_TTBR0_EL1), access_vm_reg, reset_unknown, TTBR0_EL1 }, { SYS_DESC(SYS_TTBR1_EL1), access_vm_reg, reset_unknown, TTBR1_EL1 }, @@ -1571,6 +1584,9 @@ static const struct sys_reg_desc sys_reg_descs[] = { { SYS_DESC(SYS_ERXMISC0_EL1), trap_raz_wi }, { SYS_DESC(SYS_ERXMISC1_EL1), trap_raz_wi }, + { SYS_DESC(SYS_TFSR_EL1), access_mte_regs }, + { SYS_DESC(SYS_TFSRE0_EL1), access_mte_regs }, + { SYS_DESC(SYS_FAR_EL1), access_vm_reg, reset_unknown, FAR_EL1 }, { SYS_DESC(SYS_PAR_EL1), NULL, reset_unknown, PAR_EL1 }, -- 2.39.5