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-rw-r--r--arch/arm64/kvm/Kconfig4
-rw-r--r--arch/arm64/kvm/handle_exit.c11
-rw-r--r--arch/arm64/kvm/hyp/hyp-entry.S9
-rw-r--r--arch/arm64/kvm/hyp/switch.c13
-rw-r--r--arch/arm64/kvm/reset.c6
5 files changed, 30 insertions, 13 deletions
diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
index 6eaf12c1d627..52cb7ad9b2fd 100644
--- a/arch/arm64/kvm/Kconfig
+++ b/arch/arm64/kvm/Kconfig
@@ -16,9 +16,6 @@ menuconfig VIRTUALIZATION
if VIRTUALIZATION
-config KVM_ARM_VGIC_V3_ITS
- bool
-
config KVM
bool "Kernel-based Virtual Machine (KVM) support"
depends on OF
@@ -34,7 +31,6 @@ config KVM
select KVM_VFIO
select HAVE_KVM_EVENTFD
select HAVE_KVM_IRQFD
- select KVM_ARM_VGIC_V3_ITS
select KVM_ARM_PMU if HW_PERF_EVENTS
select HAVE_KVM_MSI
select HAVE_KVM_IRQCHIP
diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c
index a204adf29f0a..1bfe30dfbfe7 100644
--- a/arch/arm64/kvm/handle_exit.c
+++ b/arch/arm64/kvm/handle_exit.c
@@ -57,6 +57,16 @@ static int handle_smc(struct kvm_vcpu *vcpu, struct kvm_run *run)
return 1;
}
+/*
+ * Guest access to FP/ASIMD registers are routed to this handler only
+ * when the system doesn't support FP/ASIMD.
+ */
+static int handle_no_fpsimd(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+ kvm_inject_undefined(vcpu);
+ return 1;
+}
+
/**
* kvm_handle_wfx - handle a wait-for-interrupts or wait-for-event
* instruction executed by a guest
@@ -144,6 +154,7 @@ static exit_handle_fn arm_exit_handlers[] = {
[ESR_ELx_EC_BREAKPT_LOW]= kvm_handle_guest_debug,
[ESR_ELx_EC_BKPT32] = kvm_handle_guest_debug,
[ESR_ELx_EC_BRK64] = kvm_handle_guest_debug,
+ [ESR_ELx_EC_FP_ASIMD] = handle_no_fpsimd,
};
static exit_handle_fn kvm_get_exit_handler(struct kvm_vcpu *vcpu)
diff --git a/arch/arm64/kvm/hyp/hyp-entry.S b/arch/arm64/kvm/hyp/hyp-entry.S
index 4e92399f7105..5e9052f087f2 100644
--- a/arch/arm64/kvm/hyp/hyp-entry.S
+++ b/arch/arm64/kvm/hyp/hyp-entry.S
@@ -106,9 +106,16 @@ el1_trap:
* x0: ESR_EC
*/
- /* Guest accessed VFP/SIMD registers, save host, restore Guest */
+ /*
+ * We trap the first access to the FP/SIMD to save the host context
+ * and restore the guest context lazily.
+ * If FP/SIMD is not implemented, handle the trap and inject an
+ * undefined instruction exception to the guest.
+ */
+alternative_if_not ARM64_HAS_NO_FPSIMD
cmp x0, #ESR_ELx_EC_FP_ASIMD
b.eq __fpsimd_guest_restore
+alternative_else_nop_endif
mrs x1, tpidr_el2
mov x0, #ARM_EXCEPTION_TRAP
diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index 83037cd62d01..75e83dd40d43 100644
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -21,6 +21,7 @@
#include <asm/kvm_asm.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_hyp.h>
+#include <asm/fpsimd.h>
static bool __hyp_text __fpsimd_enabled_nvhe(void)
{
@@ -76,16 +77,24 @@ static void __hyp_text __activate_traps(struct kvm_vcpu *vcpu)
* traps are only taken to EL2 if the operation would not otherwise
* trap to EL1. Therefore, always make sure that for 32-bit guests,
* we set FPEXC.EN to prevent traps to EL1, when setting the TFP bit.
+ * If FP/ASIMD is not implemented, FPEXC is UNDEFINED and any access to
+ * it will cause an exception.
*/
val = vcpu->arch.hcr_el2;
- if (!(val & HCR_RW)) {
+ if (!(val & HCR_RW) && system_supports_fpsimd()) {
write_sysreg(1 << 30, fpexc32_el2);
isb();
}
write_sysreg(val, hcr_el2);
/* Trap on AArch32 cp15 c15 accesses (EL1 or EL0) */
write_sysreg(1 << 15, hstr_el2);
- /* Make sure we trap PMU access from EL0 to EL2 */
+ /*
+ * Make sure we trap PMU access from EL0 to EL2. Also sanitize
+ * PMSELR_EL0 to make sure it never contains the cycle
+ * counter, which could make a PMXEVCNTR_EL0 access UNDEF at
+ * EL1 instead of being trapped to EL2.
+ */
+ write_sysreg(0, pmselr_el0);
write_sysreg(ARMV8_PMU_USERENR_MASK, pmuserenr_el0);
write_sysreg(vcpu->arch.mdcr_el2, mdcr_el2);
__activate_traps_arch()();
diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c
index 5bc460884639..e95d4f68bf54 100644
--- a/arch/arm64/kvm/reset.c
+++ b/arch/arm64/kvm/reset.c
@@ -86,12 +86,6 @@ int kvm_arch_dev_ioctl_check_extension(struct kvm *kvm, long ext)
case KVM_CAP_VCPU_ATTRIBUTES:
r = 1;
break;
- case KVM_CAP_MSI_DEVID:
- if (!kvm)
- r = -EINVAL;
- else
- r = kvm->arch.vgic.msis_require_devid;
- break;
default:
r = 0;
}
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