diff options
Diffstat (limited to 'arch/arm64/kvm')
-rw-r--r-- | arch/arm64/kvm/handle_exit.c | 18 | ||||
-rw-r--r-- | arch/arm64/kvm/hyp/entry.S | 1 | ||||
-rw-r--r-- | arch/arm64/kvm/hyp/hyp-entry.S | 4 | ||||
-rw-r--r-- | arch/arm64/kvm/hyp/switch.c | 25 | ||||
-rw-r--r-- | arch/arm64/kvm/hyp/tlb.c | 71 | ||||
-rw-r--r-- | arch/arm64/kvm/sys_regs.c | 8 |
6 files changed, 114 insertions, 13 deletions
diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index 35a81bebd02b..ab35929dcb3c 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -173,6 +173,23 @@ static int handle_sve(struct kvm_vcpu *vcpu, struct kvm_run *run) return 1; } +/* + * Guest usage of a ptrauth instruction (which the guest EL1 did not turn into + * a NOP). + */ +static int kvm_handle_ptrauth(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + /* + * We don't currently support ptrauth in a guest, and we mask the ID + * registers to prevent well-behaved guests from trying to make use of + * it. + * + * Inject an UNDEF, as if the feature really isn't present. + */ + kvm_inject_undefined(vcpu); + return 1; +} + static exit_handle_fn arm_exit_handlers[] = { [0 ... ESR_ELx_EC_MAX] = kvm_handle_unknown_ec, [ESR_ELx_EC_WFx] = kvm_handle_wfx, @@ -195,6 +212,7 @@ static exit_handle_fn arm_exit_handlers[] = { [ESR_ELx_EC_BKPT32] = kvm_handle_guest_debug, [ESR_ELx_EC_BRK64] = kvm_handle_guest_debug, [ESR_ELx_EC_FP_ASIMD] = handle_no_fpsimd, + [ESR_ELx_EC_PAC] = kvm_handle_ptrauth, }; static exit_handle_fn kvm_get_exit_handler(struct kvm_vcpu *vcpu) diff --git a/arch/arm64/kvm/hyp/entry.S b/arch/arm64/kvm/hyp/entry.S index fad1e164fe48..675fdc186e3b 100644 --- a/arch/arm64/kvm/hyp/entry.S +++ b/arch/arm64/kvm/hyp/entry.S @@ -83,6 +83,7 @@ ENTRY(__guest_enter) // Do not touch any register after this! eret + sb ENDPROC(__guest_enter) ENTRY(__guest_exit) diff --git a/arch/arm64/kvm/hyp/hyp-entry.S b/arch/arm64/kvm/hyp/hyp-entry.S index b1f14f736962..73c1b483ec39 100644 --- a/arch/arm64/kvm/hyp/hyp-entry.S +++ b/arch/arm64/kvm/hyp/hyp-entry.S @@ -96,6 +96,7 @@ el1_sync: // Guest trapped into EL2 do_el2_call eret + sb el1_hvc_guest: /* @@ -146,6 +147,7 @@ wa_epilogue: mov x0, xzr add sp, sp, #16 eret + sb el1_trap: get_vcpu_ptr x1, x0 @@ -199,6 +201,7 @@ el2_error: b.ne __hyp_panic mov x0, #(1 << ARM_EXIT_WITH_SERROR_BIT) eret + sb ENTRY(__hyp_do_panic) mov lr, #(PSR_F_BIT | PSR_I_BIT | PSR_A_BIT | PSR_D_BIT |\ @@ -207,6 +210,7 @@ ENTRY(__hyp_do_panic) ldr lr, =panic msr elr_el2, lr eret + sb ENDPROC(__hyp_do_panic) ENTRY(__hyp_panic) diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c index 7cc175c88a37..63ac10ead3a8 100644 --- a/arch/arm64/kvm/hyp/switch.c +++ b/arch/arm64/kvm/hyp/switch.c @@ -143,6 +143,14 @@ static void deactivate_traps_vhe(void) { extern char vectors[]; /* kernel exception vectors */ write_sysreg(HCR_HOST_VHE_FLAGS, hcr_el2); + + /* + * ARM erratum 1165522 requires the actual execution of the above + * before we can switch to the EL2/EL0 translation regime used by + * the host. + */ + asm(ALTERNATIVE("nop", "isb", ARM64_WORKAROUND_1165522)); + write_sysreg(CPACR_EL1_DEFAULT, cpacr_el1); write_sysreg(vectors, vbar_el1); } @@ -157,7 +165,7 @@ static void __hyp_text __deactivate_traps_nvhe(void) mdcr_el2 |= MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT; write_sysreg(mdcr_el2, mdcr_el2); - write_sysreg(HCR_RW, hcr_el2); + write_sysreg(HCR_HOST_NVHE_FLAGS, hcr_el2); write_sysreg(CPTR_EL2_DEFAULT, cptr_el2); } @@ -499,8 +507,19 @@ int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu) sysreg_save_host_state_vhe(host_ctxt); - __activate_traps(vcpu); + /* + * ARM erratum 1165522 requires us to configure both stage 1 and + * stage 2 translation for the guest context before we clear + * HCR_EL2.TGE. + * + * We have already configured the guest's stage 1 translation in + * kvm_vcpu_load_sysregs above. We must now call __activate_vm + * before __activate_traps, because __activate_vm configures + * stage 2 translation, and __activate_traps clear HCR_EL2.TGE + * (among other things). + */ __activate_vm(vcpu->kvm); + __activate_traps(vcpu); sysreg_restore_guest_state_vhe(guest_ctxt); __debug_switch_to_guest(vcpu); @@ -545,8 +564,8 @@ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu) __sysreg_save_state_nvhe(host_ctxt); - __activate_traps(vcpu); __activate_vm(kern_hyp_va(vcpu->kvm)); + __activate_traps(vcpu); __hyp_vgic_restore_state(vcpu); __timer_enable_traps(vcpu); diff --git a/arch/arm64/kvm/hyp/tlb.c b/arch/arm64/kvm/hyp/tlb.c index 4dbd9c69a96d..76c30866069e 100644 --- a/arch/arm64/kvm/hyp/tlb.c +++ b/arch/arm64/kvm/hyp/tlb.c @@ -15,20 +15,54 @@ * along with this program. If not, see <http://www.gnu.org/licenses/>. */ +#include <linux/irqflags.h> + #include <asm/kvm_hyp.h> #include <asm/kvm_mmu.h> #include <asm/tlbflush.h> -static void __hyp_text __tlb_switch_to_guest_vhe(struct kvm *kvm) +struct tlb_inv_context { + unsigned long flags; + u64 tcr; + u64 sctlr; +}; + +static void __hyp_text __tlb_switch_to_guest_vhe(struct kvm *kvm, + struct tlb_inv_context *cxt) { u64 val; + local_irq_save(cxt->flags); + + if (cpus_have_const_cap(ARM64_WORKAROUND_1165522)) { + /* + * For CPUs that are affected by ARM erratum 1165522, we + * cannot trust stage-1 to be in a correct state at that + * point. Since we do not want to force a full load of the + * vcpu state, we prevent the EL1 page-table walker to + * allocate new TLBs. This is done by setting the EPD bits + * in the TCR_EL1 register. We also need to prevent it to + * allocate IPA->PA walks, so we enable the S1 MMU... + */ + val = cxt->tcr = read_sysreg_el1(tcr); + val |= TCR_EPD1_MASK | TCR_EPD0_MASK; + write_sysreg_el1(val, tcr); + val = cxt->sctlr = read_sysreg_el1(sctlr); + val |= SCTLR_ELx_M; + write_sysreg_el1(val, sctlr); + } + /* * With VHE enabled, we have HCR_EL2.{E2H,TGE} = {1,1}, and * most TLB operations target EL2/EL0. In order to affect the * guest TLBs (EL1/EL0), we need to change one of these two * bits. Changing E2H is impossible (goodbye TTBR1_EL2), so * let's flip TGE before executing the TLB operation. + * + * ARM erratum 1165522 requires some special handling (again), + * as we need to make sure both stages of translation are in + * place before clearing TGE. __load_guest_stage2() already + * has an ISB in order to deal with this. */ __load_guest_stage2(kvm); val = read_sysreg(hcr_el2); @@ -37,7 +71,8 @@ static void __hyp_text __tlb_switch_to_guest_vhe(struct kvm *kvm) isb(); } -static void __hyp_text __tlb_switch_to_guest_nvhe(struct kvm *kvm) +static void __hyp_text __tlb_switch_to_guest_nvhe(struct kvm *kvm, + struct tlb_inv_context *cxt) { __load_guest_stage2(kvm); isb(); @@ -48,7 +83,8 @@ static hyp_alternate_select(__tlb_switch_to_guest, __tlb_switch_to_guest_vhe, ARM64_HAS_VIRT_HOST_EXTN); -static void __hyp_text __tlb_switch_to_host_vhe(struct kvm *kvm) +static void __hyp_text __tlb_switch_to_host_vhe(struct kvm *kvm, + struct tlb_inv_context *cxt) { /* * We're done with the TLB operation, let's restore the host's @@ -56,9 +92,19 @@ static void __hyp_text __tlb_switch_to_host_vhe(struct kvm *kvm) */ write_sysreg(0, vttbr_el2); write_sysreg(HCR_HOST_VHE_FLAGS, hcr_el2); + isb(); + + if (cpus_have_const_cap(ARM64_WORKAROUND_1165522)) { + /* Restore the registers to what they were */ + write_sysreg_el1(cxt->tcr, tcr); + write_sysreg_el1(cxt->sctlr, sctlr); + } + + local_irq_restore(cxt->flags); } -static void __hyp_text __tlb_switch_to_host_nvhe(struct kvm *kvm) +static void __hyp_text __tlb_switch_to_host_nvhe(struct kvm *kvm, + struct tlb_inv_context *cxt) { write_sysreg(0, vttbr_el2); } @@ -70,11 +116,13 @@ static hyp_alternate_select(__tlb_switch_to_host, void __hyp_text __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa) { + struct tlb_inv_context cxt; + dsb(ishst); /* Switch to requested VMID */ kvm = kern_hyp_va(kvm); - __tlb_switch_to_guest()(kvm); + __tlb_switch_to_guest()(kvm, &cxt); /* * We could do so much better if we had the VA as well. @@ -117,36 +165,39 @@ void __hyp_text __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa) if (!has_vhe() && icache_is_vpipt()) __flush_icache_all(); - __tlb_switch_to_host()(kvm); + __tlb_switch_to_host()(kvm, &cxt); } void __hyp_text __kvm_tlb_flush_vmid(struct kvm *kvm) { + struct tlb_inv_context cxt; + dsb(ishst); /* Switch to requested VMID */ kvm = kern_hyp_va(kvm); - __tlb_switch_to_guest()(kvm); + __tlb_switch_to_guest()(kvm, &cxt); __tlbi(vmalls12e1is); dsb(ish); isb(); - __tlb_switch_to_host()(kvm); + __tlb_switch_to_host()(kvm, &cxt); } void __hyp_text __kvm_tlb_flush_local_vmid(struct kvm_vcpu *vcpu) { struct kvm *kvm = kern_hyp_va(kern_hyp_va(vcpu)->kvm); + struct tlb_inv_context cxt; /* Switch to requested VMID */ - __tlb_switch_to_guest()(kvm); + __tlb_switch_to_guest()(kvm, &cxt); __tlbi(vmalle1); dsb(nsh); isb(); - __tlb_switch_to_host()(kvm); + __tlb_switch_to_host()(kvm, &cxt); } void __hyp_text __kvm_flush_vm_context(void) diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 22fbbdbece3c..1ca592d38c3c 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -1040,6 +1040,14 @@ static u64 read_id_reg(struct sys_reg_desc const *r, bool raz) kvm_debug("SVE unsupported for guests, suppressing\n"); val &= ~(0xfUL << ID_AA64PFR0_SVE_SHIFT); + } else if (id == SYS_ID_AA64ISAR1_EL1) { + const u64 ptrauth_mask = (0xfUL << ID_AA64ISAR1_APA_SHIFT) | + (0xfUL << ID_AA64ISAR1_API_SHIFT) | + (0xfUL << ID_AA64ISAR1_GPA_SHIFT) | + (0xfUL << ID_AA64ISAR1_GPI_SHIFT); + if (val & ptrauth_mask) + kvm_debug("ptrauth unsupported for guests, suppressing\n"); + val &= ~ptrauth_mask; } else if (id == SYS_ID_AA64MMFR1_EL1) { if (val & (0xfUL << ID_AA64MMFR1_LOR_SHIFT)) kvm_debug("LORegions unsupported for guests, suppressing\n"); |