diff options
Diffstat (limited to 'arch/arm64/kvm/hyp')
| -rw-r--r-- | arch/arm64/kvm/hyp/hyp-entry.S | 9 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/switch.c | 5 |
2 files changed, 12 insertions, 2 deletions
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 0c848c18ca44..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) { @@ -76,9 +77,11 @@ 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(); } |