diff options
Diffstat (limited to 'arch/arm64/kvm/hyp/switch.c')
| -rw-r--r-- | arch/arm64/kvm/hyp/switch.c | 13 |
1 files changed, 11 insertions, 2 deletions
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()(); |