From a354a64d91eec3e0f8ef0eed575b480fd75b999c Mon Sep 17 00:00:00 2001 From: Suzuki K Poulose Date: Tue, 23 Mar 2021 12:06:30 +0000 Subject: KVM: arm64: Disable guest access to trace filter controls Disable guest access to the Trace Filter control registers. We do not advertise the Trace filter feature to the guest (ID_AA64DFR0_EL1: TRACE_FILT is cleared) already, but the guest can still access the TRFCR_EL1 unless we trap it. This will also make sure that the guest cannot fiddle with the filtering controls set by a nvhe host. Cc: Marc Zyngier Cc: Will Deacon Cc: Mark Rutland Cc: Catalin Marinas Signed-off-by: Suzuki K Poulose Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20210323120647.454211-3-suzuki.poulose@arm.com --- arch/arm64/kvm/debug.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/arm64/kvm') diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c index 7a7e425616b5..dbc890511631 100644 --- a/arch/arm64/kvm/debug.c +++ b/arch/arm64/kvm/debug.c @@ -89,6 +89,7 @@ void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu) * - Debug ROM Address (MDCR_EL2_TDRA) * - OS related registers (MDCR_EL2_TDOSA) * - Statistical profiler (MDCR_EL2_TPMS/MDCR_EL2_E2PB) + * - Self-hosted Trace Filter controls (MDCR_EL2_TTRF) * * Additionally, KVM only traps guest accesses to the debug registers if * the guest is not actively using them (see the KVM_ARM64_DEBUG_DIRTY @@ -112,6 +113,7 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) vcpu->arch.mdcr_el2 = __this_cpu_read(mdcr_el2) & MDCR_EL2_HPMN_MASK; vcpu->arch.mdcr_el2 |= (MDCR_EL2_TPM | MDCR_EL2_TPMS | + MDCR_EL2_TTRF | MDCR_EL2_TPMCR | MDCR_EL2_TDRA | MDCR_EL2_TDOSA); -- cgit From af22df997d71c32304d6835a8b690281063b8010 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 23 Mar 2021 16:08:18 +0000 Subject: KVM: arm64: Fix CPU interface MMIO compatibility detection In order to detect whether a GICv3 CPU interface is MMIO capable, we switch ICC_SRE_EL1.SRE to 0 and check whether it sticks. However, this is only possible if *ALL* of the HCR_EL2 interrupt overrides are set, and the CPU is perfectly allowed to ignore the write to ICC_SRE_EL1 otherwise. This leads KVM to pretend that a whole bunch of ARMv8.0 CPUs aren't MMIO-capable, and breaks VMs that should work correctly otherwise. Fix this by setting IMO/FMO/IMO before touching ICC_SRE_EL1, and clear them afterwards. This allows us to reliably detect the CPU interface capabilities. Tested-by: Shameerali Kolothum Thodi Fixes: 9739f6ef053f ("KVM: arm64: Workaround firmware wrongly advertising GICv2-on-v3 compatibility") Signed-off-by: Marc Zyngier --- arch/arm64/kvm/hyp/vgic-v3-sr.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'arch/arm64/kvm') diff --git a/arch/arm64/kvm/hyp/vgic-v3-sr.c b/arch/arm64/kvm/hyp/vgic-v3-sr.c index ee3682b9873c..39f8f7f9227c 100644 --- a/arch/arm64/kvm/hyp/vgic-v3-sr.c +++ b/arch/arm64/kvm/hyp/vgic-v3-sr.c @@ -429,6 +429,13 @@ u64 __vgic_v3_get_gic_config(void) if (has_vhe()) flags = local_daif_save(); + /* + * Table 11-2 "Permitted ICC_SRE_ELx.SRE settings" indicates + * that to be able to set ICC_SRE_EL1.SRE to 0, all the + * interrupt overrides must be set. You've got to love this. + */ + sysreg_clear_set(hcr_el2, 0, HCR_AMO | HCR_FMO | HCR_IMO); + isb(); write_gicreg(0, ICC_SRE_EL1); isb(); @@ -436,6 +443,8 @@ u64 __vgic_v3_get_gic_config(void) write_gicreg(sre, ICC_SRE_EL1); isb(); + sysreg_clear_set(hcr_el2, HCR_AMO | HCR_FMO | HCR_IMO, 0); + isb(); if (has_vhe()) local_daif_restore(flags); -- cgit