From: Oliver Upton oliver.upton@linux.dev
[ Upstream commit f3c6efc72f3b20ec23566e768979802f0a398f04 ]
KVM does not support AArch32 on asymmetric systems. To that end, enforce AArch64-only behavior on PMCR_EL1.LC when on an asymmetric system.
Fixes: 2122a833316f ("arm64: Allow mismatched 32-bit EL0 support") Signed-off-by: Oliver Upton oliver.upton@linux.dev Signed-off-by: Marc Zyngier maz@kernel.org Link: https://lore.kernel.org/r/20220816192554.1455559-2-oliver.upton@linux.dev Signed-off-by: Sasha Levin sashal@kernel.org --- arch/arm64/include/asm/kvm_host.h | 4 ++++ arch/arm64/kvm/arm.c | 3 +-- arch/arm64/kvm/sys_regs.c | 4 ++-- 3 files changed, 7 insertions(+), 4 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index de32152cea04..7aaf75577096 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -838,6 +838,10 @@ bool kvm_arm_vcpu_is_finalized(struct kvm_vcpu *vcpu); (system_supports_mte() && \ test_bit(KVM_ARCH_FLAG_MTE_ENABLED, &(kvm)->arch.flags))
+#define kvm_supports_32bit_el0() \ + (system_supports_32bit_el0() && \ + !static_branch_unlikely(&arm64_mismatched_32bit_el0)) + int kvm_trng_call(struct kvm_vcpu *vcpu); #ifdef CONFIG_KVM extern phys_addr_t hyp_mem_base; diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 83a7f61354d3..e21b24574118 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -751,8 +751,7 @@ static bool vcpu_mode_is_bad_32bit(struct kvm_vcpu *vcpu) if (likely(!vcpu_mode_is_32bit(vcpu))) return false;
- return !system_supports_32bit_el0() || - static_branch_unlikely(&arm64_mismatched_32bit_el0); + return !kvm_supports_32bit_el0(); }
/** diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index c06c0477fab5..be7edd21537f 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -692,7 +692,7 @@ static void reset_pmcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r) */ val = ((pmcr & ~ARMV8_PMU_PMCR_MASK) | (ARMV8_PMU_PMCR_MASK & 0xdecafbad)) & (~ARMV8_PMU_PMCR_E); - if (!system_supports_32bit_el0()) + if (!kvm_supports_32bit_el0()) val |= ARMV8_PMU_PMCR_LC; __vcpu_sys_reg(vcpu, r->reg) = val; } @@ -741,7 +741,7 @@ static bool access_pmcr(struct kvm_vcpu *vcpu, struct sys_reg_params *p, val = __vcpu_sys_reg(vcpu, PMCR_EL0); val &= ~ARMV8_PMU_PMCR_MASK; val |= p->regval & ARMV8_PMU_PMCR_MASK; - if (!system_supports_32bit_el0()) + if (!kvm_supports_32bit_el0()) val |= ARMV8_PMU_PMCR_LC; __vcpu_sys_reg(vcpu, PMCR_EL0) = val; kvm_pmu_handle_pmcr(vcpu, val);