diff options
Diffstat (limited to 'arch/arm64/kvm/hyp/vhe/switch.c')
| -rw-r--r-- | arch/arm64/kvm/hyp/vhe/switch.c | 48 |
1 files changed, 44 insertions, 4 deletions
diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c index 731a0378ed13..c9b330dc2066 100644 --- a/arch/arm64/kvm/hyp/vhe/switch.c +++ b/arch/arm64/kvm/hyp/vhe/switch.c @@ -48,21 +48,46 @@ DEFINE_PER_CPU(unsigned long, kvm_hyp_vector); static u64 __compute_hcr(struct kvm_vcpu *vcpu) { + u64 guest_hcr = __vcpu_sys_reg(vcpu, HCR_EL2); u64 hcr = vcpu->arch.hcr_el2; if (!vcpu_has_nv(vcpu)) return hcr; + /* + * We rely on the invariant that a vcpu entered from HYP + * context must also exit in the same context, as only an ERET + * instruction can kick us out of it, and we obviously trap + * that sucker. PSTATE.M will get fixed-up on exit. + */ if (is_hyp_ctxt(vcpu)) { + host_data_set_flag(VCPU_IN_HYP_CONTEXT); + hcr |= HCR_NV | HCR_NV2 | HCR_AT | HCR_TTLB; if (!vcpu_el2_e2h_is_set(vcpu)) hcr |= HCR_NV1; write_sysreg_s(vcpu->arch.ctxt.vncr_array, SYS_VNCR_EL2); + } else { + host_data_clear_flag(VCPU_IN_HYP_CONTEXT); + + if (guest_hcr & HCR_NV) { + u64 va = __fix_to_virt(vncr_fixmap(smp_processor_id())); + + /* Inherit the low bits from the actual register */ + va |= __vcpu_sys_reg(vcpu, VNCR_EL2) & GENMASK(PAGE_SHIFT - 1, 0); + write_sysreg_s(va, SYS_VNCR_EL2); + + /* Force NV2 in case the guest is forgetful... */ + guest_hcr |= HCR_NV2; + } } - return hcr | (__vcpu_sys_reg(vcpu, HCR_EL2) & ~NV_HCR_GUEST_EXCLUDE); + BUG_ON(host_data_test_flag(VCPU_IN_HYP_CONTEXT) && + host_data_test_flag(L1_VNCR_MAPPED)); + + return hcr | (guest_hcr & ~NV_HCR_GUEST_EXCLUDE); } static void __activate_cptr_traps(struct kvm_vcpu *vcpu) @@ -184,7 +209,7 @@ static void __deactivate_traps(struct kvm_vcpu *vcpu) ___deactivate_traps(vcpu); - write_sysreg(HCR_HOST_VHE_FLAGS, hcr_el2); + write_sysreg_hcr(HCR_HOST_VHE_FLAGS); if (has_cntpoff()) { struct timer_map map; @@ -459,6 +484,14 @@ static bool kvm_hyp_handle_tlbi_el2(struct kvm_vcpu *vcpu, u64 *exit_code) if (ret) return false; + /* + * If we have to check for any VNCR mapping being invalidated, + * go back to the slow path for further processing. + */ + if (vcpu_el2_e2h_is_set(vcpu) && vcpu_el2_tge_is_set(vcpu) && + atomic_read(&vcpu->kvm->arch.vncr_map_count)) + return false; + __kvm_skip_instr(vcpu); return true; @@ -568,9 +601,12 @@ static inline bool fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code) /* * If we were in HYP context on entry, adjust the PSTATE view - * so that the usual helpers work correctly. + * so that the usual helpers work correctly. This enforces our + * invariant that the guest's HYP context status is preserved + * across a run. */ - if (vcpu_has_nv(vcpu) && (read_sysreg(hcr_el2) & HCR_NV)) { + if (vcpu_has_nv(vcpu) && + unlikely(host_data_test_flag(VCPU_IN_HYP_CONTEXT))) { u64 mode = *vcpu_cpsr(vcpu) & (PSR_MODE_MASK | PSR_MODE32_BIT); switch (mode) { @@ -586,6 +622,10 @@ static inline bool fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code) *vcpu_cpsr(vcpu) |= mode; } + /* Apply extreme paranoia! */ + BUG_ON(vcpu_has_nv(vcpu) && + !!host_data_test_flag(VCPU_IN_HYP_CONTEXT) != is_hyp_ctxt(vcpu)); + return __fixup_guest_exit(vcpu, exit_code, hyp_exit_handlers); } |