diff options
Diffstat (limited to 'arch/arm64/kvm/hyp/switch.c')
-rw-r--r-- | arch/arm64/kvm/hyp/switch.c | 206 |
1 files changed, 186 insertions, 20 deletions
diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c index f0e7bdfae134..437cfad5e3d8 100644 --- a/arch/arm64/kvm/hyp/switch.c +++ b/arch/arm64/kvm/hyp/switch.c @@ -15,7 +15,53 @@ * along with this program. If not, see <http://www.gnu.org/licenses/>. */ -#include "hyp.h" +#include <linux/types.h> +#include <asm/kvm_asm.h> +#include <asm/kvm_hyp.h> + +static bool __hyp_text __fpsimd_enabled_nvhe(void) +{ + return !(read_sysreg(cptr_el2) & CPTR_EL2_TFP); +} + +static bool __hyp_text __fpsimd_enabled_vhe(void) +{ + return !!(read_sysreg(cpacr_el1) & CPACR_EL1_FPEN); +} + +static hyp_alternate_select(__fpsimd_is_enabled, + __fpsimd_enabled_nvhe, __fpsimd_enabled_vhe, + ARM64_HAS_VIRT_HOST_EXTN); + +bool __hyp_text __fpsimd_enabled(void) +{ + return __fpsimd_is_enabled()(); +} + +static void __hyp_text __activate_traps_vhe(void) +{ + u64 val; + + val = read_sysreg(cpacr_el1); + val |= CPACR_EL1_TTA; + val &= ~CPACR_EL1_FPEN; + write_sysreg(val, cpacr_el1); + + write_sysreg(__kvm_hyp_vector, vbar_el1); +} + +static void __hyp_text __activate_traps_nvhe(void) +{ + u64 val; + + val = CPTR_EL2_DEFAULT; + val |= CPTR_EL2_TTA | CPTR_EL2_TFP; + write_sysreg(val, cptr_el2); +} + +static hyp_alternate_select(__activate_traps_arch, + __activate_traps_nvhe, __activate_traps_vhe, + ARM64_HAS_VIRT_HOST_EXTN); static void __hyp_text __activate_traps(struct kvm_vcpu *vcpu) { @@ -36,20 +82,37 @@ static void __hyp_text __activate_traps(struct kvm_vcpu *vcpu) 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 */ + write_sysreg(ARMV8_PMU_USERENR_MASK, pmuserenr_el0); + write_sysreg(vcpu->arch.mdcr_el2, mdcr_el2); + __activate_traps_arch()(); +} - val = CPTR_EL2_DEFAULT; - val |= CPTR_EL2_TTA | CPTR_EL2_TFP; - write_sysreg(val, cptr_el2); +static void __hyp_text __deactivate_traps_vhe(void) +{ + extern char vectors[]; /* kernel exception vectors */ - write_sysreg(vcpu->arch.mdcr_el2, mdcr_el2); + write_sysreg(HCR_HOST_VHE_FLAGS, hcr_el2); + write_sysreg(CPACR_EL1_FPEN, cpacr_el1); + write_sysreg(vectors, vbar_el1); } -static void __hyp_text __deactivate_traps(struct kvm_vcpu *vcpu) +static void __hyp_text __deactivate_traps_nvhe(void) { write_sysreg(HCR_RW, hcr_el2); + write_sysreg(CPTR_EL2_DEFAULT, cptr_el2); +} + +static hyp_alternate_select(__deactivate_traps_arch, + __deactivate_traps_nvhe, __deactivate_traps_vhe, + ARM64_HAS_VIRT_HOST_EXTN); + +static void __hyp_text __deactivate_traps(struct kvm_vcpu *vcpu) +{ + __deactivate_traps_arch()(); write_sysreg(0, hstr_el2); write_sysreg(read_sysreg(mdcr_el2) & MDCR_EL2_HPMN_MASK, mdcr_el2); - write_sysreg(CPTR_EL2_DEFAULT, cptr_el2); + write_sysreg(0, pmuserenr_el0); } static void __hyp_text __activate_vm(struct kvm_vcpu *vcpu) @@ -89,6 +152,86 @@ static void __hyp_text __vgic_restore_state(struct kvm_vcpu *vcpu) __vgic_call_restore_state()(vcpu); } +static bool __hyp_text __true_value(void) +{ + return true; +} + +static bool __hyp_text __false_value(void) +{ + return false; +} + +static hyp_alternate_select(__check_arm_834220, + __false_value, __true_value, + ARM64_WORKAROUND_834220); + +static bool __hyp_text __translate_far_to_hpfar(u64 far, u64 *hpfar) +{ + u64 par, tmp; + + /* + * Resolve the IPA the hard way using the guest VA. + * + * Stage-1 translation already validated the memory access + * rights. As such, we can use the EL1 translation regime, and + * don't have to distinguish between EL0 and EL1 access. + * + * We do need to save/restore PAR_EL1 though, as we haven't + * saved the guest context yet, and we may return early... + */ + par = read_sysreg(par_el1); + asm volatile("at s1e1r, %0" : : "r" (far)); + isb(); + + tmp = read_sysreg(par_el1); + write_sysreg(par, par_el1); + + if (unlikely(tmp & 1)) + return false; /* Translation failed, back to guest */ + + /* Convert PAR to HPFAR format */ + *hpfar = ((tmp >> 12) & ((1UL << 36) - 1)) << 4; + return true; +} + +static bool __hyp_text __populate_fault_info(struct kvm_vcpu *vcpu) +{ + u64 esr = read_sysreg_el2(esr); + u8 ec = esr >> ESR_ELx_EC_SHIFT; + u64 hpfar, far; + + vcpu->arch.fault.esr_el2 = esr; + + if (ec != ESR_ELx_EC_DABT_LOW && ec != ESR_ELx_EC_IABT_LOW) + return true; + + far = read_sysreg_el2(far); + + /* + * The HPFAR can be invalid if the stage 2 fault did not + * happen during a stage 1 page table walk (the ESR_EL2.S1PTW + * bit is clear) and one of the two following cases are true: + * 1. The fault was due to a permission fault + * 2. The processor carries errata 834220 + * + * Therefore, for all non S1PTW faults where we either have a + * permission fault or the errata workaround is enabled, we + * resolve the IPA using the AT instruction. + */ + if (!(esr & ESR_ELx_S1PTW) && + (__check_arm_834220()() || (esr & ESR_ELx_FSC_TYPE) == FSC_PERM)) { + if (!__translate_far_to_hpfar(far, &hpfar)) + return false; + } else { + hpfar = read_sysreg(hpfar_el2); + } + + vcpu->arch.fault.far_el2 = far; + vcpu->arch.fault.hpfar_el2 = hpfar; + return true; +} + static int __hyp_text __guest_run(struct kvm_vcpu *vcpu) { struct kvm_cpu_context *host_ctxt; @@ -102,7 +245,7 @@ static int __hyp_text __guest_run(struct kvm_vcpu *vcpu) host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context); guest_ctxt = &vcpu->arch.ctxt; - __sysreg_save_state(host_ctxt); + __sysreg_save_host_state(host_ctxt); __debug_cond_save_host_state(vcpu); __activate_traps(vcpu); @@ -116,16 +259,20 @@ static int __hyp_text __guest_run(struct kvm_vcpu *vcpu) * to Cortex-A57 erratum #852523. */ __sysreg32_restore_state(vcpu); - __sysreg_restore_state(guest_ctxt); + __sysreg_restore_guest_state(guest_ctxt); __debug_restore_state(vcpu, kern_hyp_va(vcpu->arch.debug_ptr), guest_ctxt); /* Jump in the fire! */ +again: exit_code = __guest_enter(vcpu, host_ctxt); /* And we're baaack! */ + if (exit_code == ARM_EXCEPTION_TRAP && !__populate_fault_info(vcpu)) + goto again; + fp_enabled = __fpsimd_enabled(); - __sysreg_save_state(guest_ctxt); + __sysreg_save_guest_state(guest_ctxt); __sysreg32_save_state(vcpu); __timer_save_state(vcpu); __vgic_save_state(vcpu); @@ -133,7 +280,7 @@ static int __hyp_text __guest_run(struct kvm_vcpu *vcpu) __deactivate_traps(vcpu); __deactivate_vm(vcpu); - __sysreg_restore_state(host_ctxt); + __sysreg_restore_host_state(host_ctxt); if (fp_enabled) { __fpsimd_save_state(&guest_ctxt->gp_regs.fp_regs); @@ -150,11 +297,34 @@ __alias(__guest_run) int __kvm_vcpu_run(struct kvm_vcpu *vcpu); static const char __hyp_panic_string[] = "HYP panic:\nPS:%08llx PC:%016llx ESR:%08llx\nFAR:%016llx HPFAR:%016llx PAR:%016llx\nVCPU:%p\n"; -void __hyp_text __noreturn __hyp_panic(void) +static void __hyp_text __hyp_call_panic_nvhe(u64 spsr, u64 elr, u64 par) { unsigned long str_va = (unsigned long)__hyp_panic_string; - u64 spsr = read_sysreg(spsr_el2); - u64 elr = read_sysreg(elr_el2); + + __hyp_do_panic(hyp_kern_va(str_va), + spsr, elr, + read_sysreg(esr_el2), read_sysreg_el2(far), + read_sysreg(hpfar_el2), par, + (void *)read_sysreg(tpidr_el2)); +} + +static void __hyp_text __hyp_call_panic_vhe(u64 spsr, u64 elr, u64 par) +{ + panic(__hyp_panic_string, + spsr, elr, + read_sysreg_el2(esr), read_sysreg_el2(far), + read_sysreg(hpfar_el2), par, + (void *)read_sysreg(tpidr_el2)); +} + +static hyp_alternate_select(__hyp_call_panic, + __hyp_call_panic_nvhe, __hyp_call_panic_vhe, + ARM64_HAS_VIRT_HOST_EXTN); + +void __hyp_text __noreturn __hyp_panic(void) +{ + u64 spsr = read_sysreg_el2(spsr); + u64 elr = read_sysreg_el2(elr); u64 par = read_sysreg(par_el1); if (read_sysreg(vttbr_el2)) { @@ -165,15 +335,11 @@ void __hyp_text __noreturn __hyp_panic(void) host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context); __deactivate_traps(vcpu); __deactivate_vm(vcpu); - __sysreg_restore_state(host_ctxt); + __sysreg_restore_host_state(host_ctxt); } /* Call panic for real */ - __hyp_do_panic(hyp_kern_va(str_va), - spsr, elr, - read_sysreg(esr_el2), read_sysreg(far_el2), - read_sysreg(hpfar_el2), par, - (void *)read_sysreg(tpidr_el2)); + __hyp_call_panic()(spsr, elr, par); unreachable(); } |