diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm64/include/asm/kvm_asm.h | 4 | ||||
| -rw-r--r-- | arch/arm64/include/asm/kvm_hyp.h | 6 | ||||
| -rw-r--r-- | arch/arm64/kernel/image-vars.h | 37 | ||||
| -rw-r--r-- | arch/arm64/kvm/arm.c | 6 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/Makefile | 2 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/hyp-entry.S | 2 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/include/hyp/switch.h | 509 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/Makefile | 2 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/switch.c | 271 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/switch.c | 936 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/sysreg-sr.c | 4 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/vhe/Makefile | 2 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/vhe/switch.c | 219 |
13 files changed, 1048 insertions, 952 deletions
diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h index 3476abb046e3..5a91aaae78d2 100644 --- a/arch/arm64/include/asm/kvm_asm.h +++ b/arch/arm64/include/asm/kvm_asm.h @@ -96,9 +96,7 @@ extern void __kvm_tlb_flush_local_vmid(struct kvm_vcpu *vcpu); extern void __kvm_timer_set_cntvoff(u64 cntvoff); -extern int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu); - -extern int __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu); +extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu); extern void __kvm_enable_ssbs(void); diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h index ce3080834bfa..82fa05d15b8b 100644 --- a/arch/arm64/include/asm/kvm_hyp.h +++ b/arch/arm64/include/asm/kvm_hyp.h @@ -81,11 +81,17 @@ void __debug_switch_to_host(struct kvm_vcpu *vcpu); void __fpsimd_save_state(struct user_fpsimd_state *fp_regs); void __fpsimd_restore_state(struct user_fpsimd_state *fp_regs); +#ifndef __KVM_NVHE_HYPERVISOR__ void activate_traps_vhe_load(struct kvm_vcpu *vcpu); void deactivate_traps_vhe_put(void); +#endif u64 __guest_enter(struct kvm_vcpu *vcpu, struct kvm_cpu_context *host_ctxt); + +void __noreturn hyp_panic(struct kvm_cpu_context *host_ctxt); +#ifdef __KVM_NVHE_HYPERVISOR__ void __noreturn __hyp_do_panic(unsigned long, ...); +#endif #endif /* __ARM64_KVM_HYP_H__ */ diff --git a/arch/arm64/kernel/image-vars.h b/arch/arm64/kernel/image-vars.h index f029f3ea7ffe..06fe9833104a 100644 --- a/arch/arm64/kernel/image-vars.h +++ b/arch/arm64/kernel/image-vars.h @@ -63,30 +63,50 @@ __efistub__ctype = _ctype; #define KVM_NVHE_ALIAS(sym) __kvm_nvhe_##sym = sym; +/* Symbols defined in aarch32.c (not yet compiled with nVHE build rules). */ +KVM_NVHE_ALIAS(kvm_skip_instr32); + /* Symbols defined in debug-sr.c (not yet compiled with nVHE build rules). */ +KVM_NVHE_ALIAS(__debug_switch_to_guest); +KVM_NVHE_ALIAS(__debug_switch_to_host); KVM_NVHE_ALIAS(__kvm_get_mdcr_el2); /* Symbols defined in entry.S (not yet compiled with nVHE build rules). */ +KVM_NVHE_ALIAS(__guest_enter); KVM_NVHE_ALIAS(__guest_exit); KVM_NVHE_ALIAS(abort_guest_exit_end); KVM_NVHE_ALIAS(abort_guest_exit_start); -/* Symbols defined in switch.c (not yet compiled with nVHE build rules). */ -KVM_NVHE_ALIAS(__kvm_vcpu_run_nvhe); -KVM_NVHE_ALIAS(hyp_panic); +/* Symbols defined in fpsimd.S (not yet compiled with nVHE build rules). */ +KVM_NVHE_ALIAS(__fpsimd_restore_state); +KVM_NVHE_ALIAS(__fpsimd_save_state); /* Symbols defined in sysreg-sr.c (not yet compiled with nVHE build rules). */ KVM_NVHE_ALIAS(__kvm_enable_ssbs); +KVM_NVHE_ALIAS(__sysreg32_restore_state); +KVM_NVHE_ALIAS(__sysreg32_save_state); +KVM_NVHE_ALIAS(__sysreg_restore_state_nvhe); +KVM_NVHE_ALIAS(__sysreg_save_state_nvhe); /* Symbols defined in timer-sr.c (not yet compiled with nVHE build rules). */ KVM_NVHE_ALIAS(__kvm_timer_set_cntvoff); +KVM_NVHE_ALIAS(__timer_disable_traps); +KVM_NVHE_ALIAS(__timer_enable_traps); + +/* Symbols defined in vgic-v2-cpuif-proxy.c (not yet compiled with nVHE build rules). */ +KVM_NVHE_ALIAS(__vgic_v2_perform_cpuif_access); /* Symbols defined in vgic-v3-sr.c (not yet compiled with nVHE build rules). */ +KVM_NVHE_ALIAS(__vgic_v3_activate_traps); +KVM_NVHE_ALIAS(__vgic_v3_deactivate_traps); KVM_NVHE_ALIAS(__vgic_v3_get_ich_vtr_el2); KVM_NVHE_ALIAS(__vgic_v3_init_lrs); +KVM_NVHE_ALIAS(__vgic_v3_perform_cpuif_access); KVM_NVHE_ALIAS(__vgic_v3_read_vmcr); KVM_NVHE_ALIAS(__vgic_v3_restore_aprs); +KVM_NVHE_ALIAS(__vgic_v3_restore_state); KVM_NVHE_ALIAS(__vgic_v3_save_aprs); +KVM_NVHE_ALIAS(__vgic_v3_save_state); KVM_NVHE_ALIAS(__vgic_v3_write_vmcr); /* Alternative callbacks for init-time patching of nVHE hyp code. */ @@ -97,11 +117,13 @@ KVM_NVHE_ALIAS(kvm_update_va_mask); /* Global kernel state accessed by nVHE hyp code. */ KVM_NVHE_ALIAS(arm64_ssbd_callback_required); KVM_NVHE_ALIAS(kvm_host_data); +KVM_NVHE_ALIAS(kvm_vgic_global_state); /* Kernel constant needed to compute idmap addresses. */ KVM_NVHE_ALIAS(kimage_voffset); /* Kernel symbols used to call panic() from nVHE hyp code (via ERET). */ +KVM_NVHE_ALIAS(__hyp_panic_string); KVM_NVHE_ALIAS(panic); /* Vectors installed by hyp-init on reset HVC. */ @@ -118,6 +140,15 @@ KVM_NVHE_ALIAS(arm64_const_caps_ready); KVM_NVHE_ALIAS(cpu_hwcap_keys); KVM_NVHE_ALIAS(cpu_hwcaps); +/* Static keys which are set if a vGIC trap should be handled in hyp. */ +KVM_NVHE_ALIAS(vgic_v2_cpuif_trap); +KVM_NVHE_ALIAS(vgic_v3_cpuif_trap); + +/* Static key checked in pmr_sync(). */ +#ifdef CONFIG_ARM64_PSEUDO_NMI +KVM_NVHE_ALIAS(gic_pmr_sync); +#endif + #endif /* CONFIG_KVM */ #endif /* __ARM64_KERNEL_IMAGE_VARS_H */ diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 34b551385153..26780b78a523 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -748,11 +748,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) trace_kvm_entry(*vcpu_pc(vcpu)); guest_enter_irqoff(); - if (has_vhe()) { - ret = kvm_vcpu_run_vhe(vcpu); - } else { - ret = kvm_call_hyp_ret(__kvm_vcpu_run_nvhe, vcpu); - } + ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu); vcpu->mode = OUTSIDE_GUEST_MODE; vcpu->stat.exits++; diff --git a/arch/arm64/kvm/hyp/Makefile b/arch/arm64/kvm/hyp/Makefile index 87d3cce2b26e..7462d3a8a6f2 100644 --- a/arch/arm64/kvm/hyp/Makefile +++ b/arch/arm64/kvm/hyp/Makefile @@ -14,7 +14,7 @@ obj-$(CONFIG_KVM) += hyp.o vhe/ nvhe/ obj-$(CONFIG_KVM_INDIRECT_VECTORS) += smccc_wa.o hyp-y := vgic-v3-sr.o timer-sr.o aarch32.o vgic-v2-cpuif-proxy.o sysreg-sr.o \ - debug-sr.o entry.o switch.o fpsimd.o + debug-sr.o entry.o fpsimd.o # KVM code is run at a different exception code with a different map, so # compiler instrumentation that inserts callbacks or checks into the code may diff --git a/arch/arm64/kvm/hyp/hyp-entry.S b/arch/arm64/kvm/hyp/hyp-entry.S index 7e3c72fa634f..8316ee67d6a0 100644 --- a/arch/arm64/kvm/hyp/hyp-entry.S +++ b/arch/arm64/kvm/hyp/hyp-entry.S @@ -182,6 +182,7 @@ el2_error: eret sb +#ifdef __KVM_NVHE_HYPERVISOR__ SYM_FUNC_START(__hyp_do_panic) mov lr, #(PSR_F_BIT | PSR_I_BIT | PSR_A_BIT | PSR_D_BIT |\ PSR_MODE_EL1h) @@ -191,6 +192,7 @@ SYM_FUNC_START(__hyp_do_panic) eret sb SYM_FUNC_END(__hyp_do_panic) +#endif SYM_CODE_START(__hyp_panic) get_host_ctxt x0, x1 diff --git a/arch/arm64/kvm/hyp/include/hyp/switch.h b/arch/arm64/kvm/hyp/include/hyp/switch.h new file mode 100644 index 000000000000..65d2a879b93b --- /dev/null +++ b/arch/arm64/kvm/hyp/include/hyp/switch.h @@ -0,0 +1,509 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2015 - ARM Ltd + * Author: Marc Zyngier <marc.zyngier@arm.com> + */ + +#ifndef __ARM64_KVM_HYP_SWITCH_H__ +#define __ARM64_KVM_HYP_SWITCH_H__ + +#include <linux/arm-smccc.h> +#include <linux/kvm_host.h> +#include <linux/types.h> +#include <linux/jump_label.h> +#include <uapi/linux/psci.h> + +#include <kvm/arm_psci.h> + +#include <asm/barrier.h> +#include <asm/cpufeature.h> +#include <asm/kprobes.h> +#include <asm/kvm_asm.h> +#include <asm/kvm_emulate.h> +#include <asm/kvm_hyp.h> +#include <asm/kvm_mmu.h> +#include <asm/fpsimd.h> +#include <asm/debug-monitors.h> +#include <asm/processor.h> +#include <asm/thread_info.h> + +extern const char __hyp_panic_string[]; + +/* Check whether the FP regs were dirtied while in the host-side run loop: */ +static inline bool __hyp_text update_fp_enabled(struct kvm_vcpu *vcpu) +{ + /* + * When the system doesn't support FP/SIMD, we cannot rely on + * the _TIF_FOREIGN_FPSTATE flag. However, we always inject an + * abort on the very first access to FP and thus we should never + * see KVM_ARM64_FP_ENABLED. For added safety, make sure we always + * trap the accesses. + */ + if (!system_supports_fpsimd() || + vcpu->arch.host_thread_info->flags & _TIF_FOREIGN_FPSTATE) + vcpu->arch.flags &= ~(KVM_ARM64_FP_ENABLED | + KVM_ARM64_FP_HOST); + + return !!(vcpu->arch.flags & KVM_ARM64_FP_ENABLED); +} + +/* Save the 32-bit only FPSIMD system register state */ +static inline void __hyp_text __fpsimd_save_fpexc32(struct kvm_vcpu *vcpu) +{ + if (!vcpu_el1_is_32bit(vcpu)) + return; + + vcpu->arch.ctxt.sys_regs[FPEXC32_EL2] = read_sysreg(fpexc32_el2); +} + +static inline void __hyp_text __activate_traps_fpsimd32(struct kvm_vcpu *vcpu) +{ + /* + * We are about to set CPTR_EL2.TFP to trap all floating point + * register accesses to EL2, however, the ARM ARM clearly states that + * 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. + */ + if (vcpu_el1_is_32bit(vcpu) && system_supports_fpsimd()) { + write_sysreg(1 << 30, fpexc32_el2); + isb(); + } +} + +static inline void __hyp_text __activate_traps_common(struct kvm_vcpu *vcpu) +{ + /* Trap on AArch32 cp15 c15 (impdef sysregs) accesses (EL1 or EL0) */ + write_sysreg(1 << 15, hstr_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); +} + +static inline void __hyp_text __deactivate_traps_common(void) +{ + write_sysreg(0, hstr_el2); + write_sysreg(0, pmuserenr_el0); +} + +static inline void __hyp_text ___activate_traps(struct kvm_vcpu *vcpu) +{ + u64 hcr = vcpu->arch.hcr_el2; + + if (cpus_have_final_cap(ARM64_WORKAROUND_CAVIUM_TX2_219_TVM)) + hcr |= HCR_TVM; + + write_sysreg(hcr, hcr_el2); + + if (cpus_have_final_cap(ARM64_HAS_RAS_EXTN) && (hcr & HCR_VSE)) + write_sysreg_s(vcpu->arch.vsesr_el2, SYS_VSESR_EL2); +} + +static inline void __hyp_text ___deactivate_traps(struct kvm_vcpu *vcpu) +{ + /* + * If we pended a virtual abort, preserve it until it gets + * cleared. See D1.14.3 (Virtual Interrupts) for details, but + * the crucial bit is "On taking a vSError interrupt, + * HCR_EL2.VSE is cleared to 0." + */ + if (vcpu->arch.hcr_el2 & HCR_VSE) { + vcpu->arch.hcr_el2 &= ~HCR_VSE; + vcpu->arch.hcr_el2 |= read_sysreg(hcr_el2) & HCR_VSE; + } +} + +static inline void __hyp_text __activate_vm(struct kvm *kvm) +{ + __load_guest_stage2(kvm); +} + +static inline 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 & SYS_PAR_EL1_F)) + return false; /* Translation failed, back to guest */ + + /* Convert PAR to HPFAR format */ + *hpfar = PAR_TO_HPFAR(tmp); + return true; +} + +static inline bool __hyp_text __populate_fault_info(struct kvm_vcpu *vcpu) +{ + u8 ec; + u64 esr; + u64 hpfar, far; + + esr = vcpu->arch.fault.esr_el2; + ec = ESR_ELx_EC(esr); + + if (ec != ESR_ELx_EC_DABT_LOW && ec != ESR_ELx_EC_IABT_LOW) + return true; + + far = read_sysreg_el2(SYS_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) && + (cpus_have_final_cap(ARM64_WORKAROUND_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; +} + +/* Check for an FPSIMD/SVE trap and handle as appropriate */ +static inline bool __hyp_text __hyp_handle_fpsimd(struct kvm_vcpu *vcpu) +{ + bool vhe, sve_guest, sve_host; + u8 hsr_ec; + + if (!system_supports_fpsimd()) + return false; + + /* + * Currently system_supports_sve() currently implies has_vhe(), + * so the check is redundant. However, has_vhe() can be determined + * statically and helps the compiler remove dead code. + */ + if (has_vhe() && system_supports_sve()) { + sve_guest = vcpu_has_sve(vcpu); + sve_host = vcpu->arch.flags & KVM_ARM64_HOST_SVE_IN_USE; + vhe = true; + } else { + sve_guest = false; + sve_host = false; + vhe = has_vhe(); + } + + hsr_ec = kvm_vcpu_trap_get_class(vcpu); + if (hsr_ec != ESR_ELx_EC_FP_ASIMD && + hsr_ec != ESR_ELx_EC_SVE) + return false; + + /* Don't handle SVE traps for non-SVE vcpus here: */ + if (!sve_guest) + if (hsr_ec != ESR_ELx_EC_FP_ASIMD) + return false; + + /* Valid trap. Switch the context: */ + + if (vhe) { + u64 reg = read_sysreg(cpacr_el1) | CPACR_EL1_FPEN; + + if (sve_guest) + reg |= CPACR_EL1_ZEN; + + write_sysreg(reg, cpacr_el1); + } else { + write_sysreg(read_sysreg(cptr_el2) & ~(u64)CPTR_EL2_TFP, + cptr_el2); + } + + isb(); + + if (vcpu->arch.flags & KVM_ARM64_FP_HOST) { + /* + * In the SVE case, VHE is assumed: it is enforced by + * Kconfig and kvm_arch_init(). + */ + if (sve_host) { + struct thread_struct *thread = container_of( + vcpu->arch.host_fpsimd_state, + struct thread_struct, uw.fpsimd_state); + + sve_save_state(sve_pffr(thread), + &vcpu->arch.host_fpsimd_state->fpsr); + } else { + __fpsimd_save_state(vcpu->arch.host_fpsimd_state); + } + + vcpu->arch.flags &= ~KVM_ARM64_FP_HOST; + } + + if (sve_guest) { + sve_load_state(vcpu_sve_pffr(vcpu), + &vcpu->arch.ctxt.gp_regs.fp_regs.fpsr, + sve_vq_from_vl(vcpu->arch.sve_max_vl) - 1); + write_sysreg_s(vcpu->arch.ctxt.sys_regs[ZCR_EL1], SYS_ZCR_EL12); + } else { + __fpsimd_restore_state(&vcpu->arch.ctxt.gp_regs.fp_regs); + } + + /* Skip restoring fpexc32 for AArch64 guests */ + if (!(read_sysreg(hcr_el2) & HCR_RW)) + write_sysreg(vcpu->arch.ctxt.sys_regs[FPEXC32_EL2], + fpexc32_el2); + + vcpu->arch.flags |= KVM_ARM64_FP_ENABLED; + + return true; +} + +static inline bool __hyp_text handle_tx2_tvm(struct kvm_vcpu *vcpu) +{ + u32 sysreg = esr_sys64_to_sysreg(kvm_vcpu_get_hsr(vcpu)); + int rt = kvm_vcpu_sys_get_rt(vcpu); + u64 val = vcpu_get_reg(vcpu, rt); + + /* + * The normal sysreg handling code expects to see the traps, + * let's not do anything here. + */ + if (vcpu->arch.hcr_el2 & HCR_TVM) + return false; + + switch (sysreg) { + case SYS_SCTLR_EL1: + write_sysreg_el1(val, SYS_SCTLR); + break; + case SYS_TTBR0_EL1: + write_sysreg_el1(val, SYS_TTBR0); + break; + case SYS_TTBR1_EL1: + write_sysreg_el1(val, SYS_TTBR1); + break; + case SYS_TCR_EL1: + write_sysreg_el1(val, SYS_TCR); + break; + case SYS_ESR_EL1: + write_sysreg_el1(val, SYS_ESR); + break; + case SYS_FAR_EL1: + write_sysreg_el1(val, SYS_FAR); + break; + case SYS_AFSR0_EL1: + write_sysreg_el1(val, SYS_AFSR0); + break; + case SYS_AFSR1_EL1: + write_sysreg_el1(val, SYS_AFSR1); + break; + case SYS_MAIR_EL1: + write_sysreg_el1(val, SYS_MAIR); + break; + case SYS_AMAIR_EL1: + write_sysreg_el1(val, SYS_AMAIR); + break; + case SYS_CONTEXTIDR_EL1: + write_sysreg_el1(val, SYS_CONTEXTIDR); + break; + default: + return false; + } + + __kvm_skip_instr(vcpu); + return true; +} + +static inline bool __hyp_text esr_is_ptrauth_trap(u32 esr) +{ + u32 ec = ESR_ELx_EC(esr); + + if (ec == ESR_ELx_EC_PAC) + return true; + + if (ec != ESR_ELx_EC_SYS64) + return false; + + switch (esr_sys64_to_sysreg(esr)) { + case SYS_APIAKEYLO_EL1: + case SYS_APIAKEYHI_EL1: + case SYS_APIBKEYLO_EL1: + case SYS_APIBKEYHI_EL1: + case SYS_APDAKEYLO_EL1: + case SYS_APDAKEYHI_EL1: + case SYS_APDBKEYLO_EL1: + case SYS_APDBKEYHI_EL1: + case SYS_APGAKEYLO_EL1: + case SYS_APGAKEYHI_EL1: + return true; + } + + return false; +} + +#define __ptrauth_save_key(regs, key) \ +({ \ + regs[key ## KEYLO_EL1] = read_sysreg_s(SYS_ ## key ## KEYLO_EL1); \ + regs[key ## KEYHI_EL1] = read_sysreg_s(SYS_ ## key ## KEYHI_EL1); \ +}) + +static inline bool __hyp_text __hyp_handle_ptrauth(struct kvm_vcpu *vcpu) +{ + struct kvm_cpu_context *ctxt; + u64 val; + + if (!vcpu_has_ptrauth(vcpu) || + !esr_is_ptrauth_trap(kvm_vcpu_get_hsr(vcpu))) + return false; + + ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt; + __ptrauth_save_key(ctxt->sys_regs, APIA); + __ptrauth_save_key(ctxt->sys_regs, APIB); + __ptrauth_save_key(ctxt->sys_regs, APDA); + __ptrauth_save_key(ctxt->sys_regs, APDB); + __ptrauth_save_key(ctxt->sys_regs, APGA); + + vcpu_ptrauth_enable(vcpu); + + val = read_sysreg(hcr_el2); + val |= (HCR_API | HCR_APK); + write_sysreg(val, hcr_el2); + + return true; +} + +/* + * Return true when we were able to fixup the guest exit and should return to + * the guest, false when we should restore the host state and return to the + * main run loop. + */ +static inline bool __hyp_text fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code) +{ + if (ARM_EXCEPTION_CODE(*exit_code) != ARM_EXCEPTION_IRQ) + vcpu->arch.fault.esr_el2 = read_sysreg_el2(SYS_ESR); + + /* + * We're using the raw exception code in order to only process + * the trap if no SError is pending. We will come back to the + * same PC once the SError has been injected, and replay the + * trapping instruction. + */ + if (*exit_code != ARM_EXCEPTION_TRAP) + goto exit; + + if (cpus_have_final_cap(ARM64_WORKAROUND_CAVIUM_TX2_219_TVM) && + kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_SYS64 && + handle_tx2_tvm(vcpu)) + return true; + + /* + * 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. + * Similarly for trapped SVE accesses. + */ + if (__hyp_handle_fpsimd(vcpu)) + return true; + + if (__hyp_handle_ptrauth(vcpu)) + return true; + + if (!__populate_fault_info(vcpu)) + return true; + + if (static_branch_unlikely(&vgic_v2_cpuif_trap)) { + bool valid; + + valid = kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_DABT_LOW && + kvm_vcpu_trap_get_fault_type(vcpu) == FSC_FAULT && + kvm_vcpu_dabt_isvalid(vcpu) && + !kvm_vcpu_dabt_isextabt(vcpu) && + !kvm_vcpu_dabt_iss1tw(vcpu); + + if (valid) { + int ret = __vgic_v2_perform_cpuif_access(vcpu); + + if (ret == 1) + return true; + + /* Promote an illegal access to an SError.*/ + if (ret == -1) + *exit_code = ARM_EXCEPTION_EL1_SERROR; + + goto exit; + } + } + + if (static_branch_unlikely(&vgic_v3_cpuif_trap) && + (kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_SYS64 || + kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_CP15_32)) { + int ret = __vgic_v3_perform_cpuif_access(vcpu); + + if (ret == 1) + return true; + } + +exit: + /* Return to the host kernel and handle the exit */ + return false; +} + +static inline bool __hyp_text __needs_ssbd_off(struct kvm_vcpu *vcpu) +{ + if (!cpus_have_final_cap(ARM64_SSBD)) + return false; + + return !(vcpu->arch.workaround_flags & VCPU_WORKAROUND_2_FLAG); +} + +static inline void __hyp_text __set_guest_arch_workaround_state(struct kvm_vcpu *vcpu) +{ +#ifdef CONFIG_ARM64_SSBD + /* + * The host runs with the workaround always present. If the + * guest wants it disabled, so be it... + */ + if (__needs_ssbd_off(vcpu) && + __hyp_this_cpu_read(arm64_ssbd_callback_required)) + arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2, 0, NULL); +#endif +} + +static inline void __hyp_text __set_host_arch_workaround_state(struct kvm_vcpu *vcpu) +{ +#ifdef CONFIG_ARM64_SSBD + /* + * If the guest has disabled the workaround, bring it back on. + */ + if (__needs_ssbd_off(vcpu) && + __hyp_this_cpu_read(arm64_ssbd_callback_required)) + arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2, 1, NULL); +#endif +} + +#endif /* __ARM64_KVM_HYP_SWITCH_H__ */ diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile index a5316e97d373..8b3ac38eaa44 100644 --- a/arch/arm64/kvm/hyp/nvhe/Makefile +++ b/arch/arm64/kvm/hyp/nvhe/Makefile @@ -6,7 +6,7 @@ asflags-y := -D__KVM_NVHE_HYPERVISOR__ ccflags-y := -D__KVM_NVHE_HYPERVISOR__ -obj-y := tlb.o hyp-init.o ../hyp-entry.o +obj-y := switch.o tlb.o hyp-init.o ../hyp-entry.o obj-y := $(patsubst %.o,%.hyp.o,$(obj-y)) extra-y := $(patsubst %.hyp.o,%.hyp.tmp.o,$(obj-y)) diff --git a/arch/arm64/kvm/hyp/nvhe/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c new file mode 100644 index 000000000000..7f6b8d3dc637 --- /dev/null +++ b/arch/arm64/kvm/hyp/nvhe/switch.c @@ -0,0 +1,271 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2015 - ARM Ltd + * Author: Marc Zyngier <marc.zyngier@arm.com> + */ + +#include <hyp/switch.h> + +#include <linux/arm-smccc.h> +#include <linux/kvm_host.h> +#include <linux/types.h> +#include <linux/jump_label.h> +#include <uapi/linux/psci.h> + +#include <kvm/arm_psci.h> + +#include <asm/barrier.h> +#include <asm/cpufeature.h> +#include <asm/kprobes.h> +#include <asm/kvm_asm.h> +#include <asm/kvm_emulate.h> +#include <asm/kvm_hyp.h> +#include <asm/kvm_mmu.h> +#include <asm/fpsimd.h> +#include <asm/debug-monitors.h> +#include <asm/processor.h> +#include <asm/thread_info.h> + +static void __hyp_text __activate_traps(struct kvm_vcpu *vcpu) +{ + u64 val; + + ___activate_traps(vcpu); + __activate_traps_common(vcpu); + + val = CPTR_EL2_DEFAULT; + val |= CPTR_EL2_TTA | CPTR_EL2_TZ | CPTR_EL2_TAM; + if (!update_fp_enabled(vcpu)) { + val |= CPTR_EL2_TFP; + __activate_traps_fpsimd32(vcpu); + } + + write_sysreg(val, cptr_el2); + + if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) { + struct kvm_cpu_context *ctxt = &vcpu->arch.ctxt; + + isb(); + /* + * At this stage, and thanks to the above isb(), S2 is + * configured and enabled. We can now restore the guest's S1 + * configuration: SCTLR, and only then TCR. + */ + write_sysreg_el1(ctxt->sys_regs[SCTLR_EL1], SYS_SCTLR); + isb(); + write_sysreg_el1(ctxt->sys_regs[TCR_EL1], SYS_TCR); + } +} + +static void __hyp_text __deactivate_traps(struct kvm_vcpu *vcpu) +{ + u64 mdcr_el2; + + ___deactivate_traps(vcpu); + + mdcr_el2 = read_sysreg(mdcr_el2); + + if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) { + u64 val; + + /* + * Set the TCR and SCTLR registers in the exact opposite + * sequence as __activate_traps (first prevent walks, + * then force the MMU on). A generous sprinkling of isb() + * ensure that things happen in this exact order. + */ + val = read_sysreg_el1(SYS_TCR); + write_sysreg_el1(val | TCR_EPD1_MASK | TCR_EPD0_MASK, SYS_TCR); + isb(); + val = read_sysreg_el1(SYS_SCTLR); + write_sysreg_el1(val | SCTLR_ELx_M, SYS_SCTLR); + isb(); + } + + __deactivate_traps_common(); + + mdcr_el2 &= MDCR_EL2_HPMN_MASK; + mdcr_el2 |= MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT; + + write_sysreg(mdcr_el2, mdcr_el2); + write_sysreg(HCR_HOST_NVHE_FLAGS, hcr_el2); + write_sysreg(CPTR_EL2_DEFAULT, cptr_el2); +} + +static void __hyp_text __deactivate_vm(struct kvm_vcpu *vcpu) +{ + write_sysreg(0, vttbr_el2); +} + +/* Save VGICv3 state on non-VHE systems */ +static void __hyp_text __hyp_vgic_save_state(struct kvm_vcpu *vcpu) +{ + if (static_branch_unlikely(&kvm_vgic_global_state.gicv3_cpuif)) { + __vgic_v3_save_state(&vcpu->arch.vgic_cpu.vgic_v3); + __vgic_v3_deactivate_traps(&vcpu->arch.vgic_cpu.vgic_v3); + } +} + +/* Restore VGICv3 state on non_VEH systems */ +static void __hyp_text __hyp_vgic_restore_state(struct kvm_vcpu *vcpu) +{ + if (static_branch_unlikely(&kvm_vgic_global_state.gicv3_cpuif)) { + __vgic_v3_activate_traps(&vcpu->arch.vgic_cpu.vgic_v3); + __vgic_v3_restore_state(&vcpu->arch.vgic_cpu.vgic_v3); + } +} + +/** + * Disable host events, enable guest events + */ +static bool __hyp_text __pmu_switch_to_guest(struct kvm_cpu_context *host_ctxt) +{ + struct kvm_host_data *host; + struct kvm_pmu_events *pmu; + + host = container_of(host_ctxt, struct kvm_host_data, host_ctxt); + pmu = &host->pmu_events; + + if (pmu->events_host) + write_sysreg(pmu->events_host, pmcntenclr_el0); + + if (pmu->events_guest) + write_sysreg(pmu->events_guest, pmcntenset_el0); + + return (pmu->events_host || pmu->events_guest); +} + +/** + * Disable guest events, enable host events + */ +static void __hyp_text __pmu_switch_to_host(struct kvm_cpu_context *host_ctxt) +{ + struct kvm_host_data *host; + struct kvm_pmu_events *pmu; + + host = container_of(host_ctxt, struct kvm_host_data, host_ctxt); + pmu = &host->pmu_events; + + if (pmu->events_guest) + write_sysreg(pmu->events_guest, pmcntenclr_el0); + + if (pmu->events_host) + write_sysreg(pmu->events_host, pmcntenset_el0); +} + +/* Switch to the guest for legacy non-VHE systems */ +int __hyp_text __kvm_vcpu_run(struct kvm_vcpu *vcpu) +{ + struct kvm_cpu_context *host_ctxt; + struct kvm_cpu_context *guest_ctxt; + bool pmu_switch_needed; + u64 exit_code; + + /* + * Having IRQs masked via PMR when entering the guest means the GIC + * will not signal the CPU of interrupts of lower priority, and the + * only way to get out will be via guest exceptions. + * Naturally, we want to avoid this. + */ + if (system_uses_irq_prio_masking()) { + gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET); + pmr_sync(); + } + + vcpu = kern_hyp_va(vcpu); + + host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt; + host_ctxt->__hyp_running_vcpu = vcpu; + guest_ctxt = &vcpu->arch.ctxt; + + pmu_switch_needed = __pmu_switch_to_guest(host_ctxt); + + __sysreg_save_state_nvhe(host_ctxt); + + /* + * We must restore the 32-bit state before the sysregs, thanks + * to erratum #852523 (Cortex-A57) or #853709 (Cortex-A72). + * + * Also, and in order to be able to deal with erratum #1319537 (A57) + * and #1319367 (A72), we must ensure that all VM-related sysreg are + * restored before we enable S2 translation. + */ + __sysreg32_restore_state(vcpu); + __sysreg_restore_state_nvhe(guest_ctxt); + + __activate_vm(kern_hyp_va(vcpu->kvm)); + __activate_traps(vcpu); + + __hyp_vgic_restore_state(vcpu); + __timer_enable_traps(vcpu); + + __debug_switch_to_guest(vcpu); + + __set_guest_arch_workaround_state(vcpu); + + do { + /* Jump in the fire! */ + exit_code = __guest_enter(vcpu, host_ctxt); + + /* And we're baaack! */ + } while (fixup_guest_exit(vcpu, &exit_code)); + + __set_host_arch_workaround_state(vcpu); + + __sysreg_save_state_nvhe(guest_ctxt); + __sysreg32_save_state(vcpu); + __timer_disable_traps(vcpu); + __hyp_vgic_save_state(vcpu); + + __deactivate_traps(vcpu); + __deactivate_vm(vcpu); + + __sysreg_restore_state_nvhe(host_ctxt); + + if (vcpu->arch.flags & KVM_ARM64_FP_ENABLED) + __fpsimd_save_fpexc32(vcpu); + + /* + * This must come after restoring the host sysregs, since a non-VHE + * system may enable SPE here and make use of the TTBRs. + */ + __debug_switch_to_host(vcpu); + + if (pmu_switch_needed) + __pmu_switch_to_host(host_ctxt); + + /* Returning to host will clear PSR.I, remask PMR if needed */ + if (system_uses_irq_prio_masking()) + gic_write_pmr(GIC_PRIO_IRQOFF); + + return exit_code; +} + +void __hyp_text __noreturn hyp_panic(struct kvm_cpu_context *host_ctxt) +{ + u64 spsr = read_sysreg_el2(SYS_SPSR); + u64 elr = read_sysreg_el2(SYS_ELR); + u64 par = read_sysreg(par_el1); + struct kvm_vcpu *vcpu = host_ctxt->__hyp_running_vcpu; + unsigned long str_va; + + if (read_sysreg(vttbr_el2)) { + __timer_disable_traps(vcpu); + __deactivate_traps(vcpu); + __deactivate_vm(vcpu); + __sysreg_restore_state_nvhe(host_ctxt); + } + + /* + * Force the panic string to be loaded from the literal pool, + * making sure it is a kernel address and not a PC-relative + * reference. + */ + asm volatile("ldr %0, =%1" : "=r" (str_va) : "S" (__hyp_panic_string)); + + __hyp_do_panic(str_va, + spsr, elr, + read_sysreg(esr_el2), read_sysreg_el2(SYS_FAR), + read_sysreg(hpfar_el2), par, vcpu); + unreachable(); +} diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c deleted file mode 100644 index 9270b14157b5..000000000000 --- a/arch/arm64/kvm/hyp/switch.c +++ /dev/null @@ -1,936 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * Copyright (C) 2015 - ARM Ltd - * Author: Marc Zyngier <marc.zyngier@arm.com> - */ - -#include <linux/arm-smccc.h> -#include <linux/kvm_host.h> -#include <linux/types.h> -#include <linux/jump_label.h> -#include <uapi/linux/psci.h> - -#include <kvm/arm_psci.h> - -#include <asm/barrier.h> -#include <asm/cpufeature.h> -#include <asm/kprobes.h> -#include <asm/kvm_asm.h> -#include <asm/kvm_emulate.h> -#include <asm/kvm_hyp.h> -#include <asm/kvm_mmu.h> -#include <asm/fpsimd.h> -#include <asm/debug-monitors.h> -#include <asm/processor.h> -#include <asm/thread_info.h> - -/* Check whether the FP regs were dirtied while in the host-side run loop: */ -static bool __hyp_text update_fp_enabled(struct kvm_vcpu *vcpu) -{ - /* - * When the system doesn't support FP/SIMD, we cannot rely on - * the _TIF_FOREIGN_FPSTATE flag. However, we always inject an - * abort on the very first access to FP and thus we should never - * see KVM_ARM64_FP_ENABLED. For added safety, make sure we always - * trap the accesses. - */ - if (!system_supports_fpsimd() || - vcpu->arch.host_thread_info->flags & _TIF_FOREIGN_FPSTATE) - vcpu->arch.flags &= ~(KVM_ARM64_FP_ENABLED | - KVM_ARM64_FP_HOST); - - return !!(vcpu->arch.flags & KVM_ARM64_FP_ENABLED); -} - -/* Save the 32-bit only FPSIMD system register state */ -static void __hyp_text __fpsimd_save_fpexc32(struct kvm_vcpu *vcpu) -{ - if (!vcpu_el1_is_32bit(vcpu)) - return; - - vcpu->arch.ctxt.sys_regs[FPEXC32_EL2] = read_sysreg(fpexc32_el2); -} - -static void __hyp_text __activate_traps_fpsimd32(struct kvm_vcpu *vcpu) -{ - /* - * We are about to set CPTR_EL2.TFP to trap all floating point - * register accesses to EL2, however, the ARM ARM clearly states that - * 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. - */ - if (vcpu_el1_is_32bit(vcpu) && system_supports_fpsimd()) { - write_sysreg(1 << 30, fpexc32_el2); - isb(); - } -} - -static void __hyp_text __activate_traps_common(struct kvm_vcpu *vcpu) -{ - /* Trap on AArch32 cp15 c15 (impdef sysregs) accesses (EL1 or EL0) */ - write_sysreg(1 << 15, hstr_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); -} - -static void __hyp_text __deactivate_traps_common(void) -{ - write_sysreg(0, hstr_el2); - write_sysreg(0, pmuserenr_el0); -} - -static void activate_traps_vhe(struct kvm_vcpu *vcpu) -{ - u64 val; - - val = read_sysreg(cpacr_el1); - val |= CPACR_EL1_TTA; - val &= ~CPACR_EL1_ZEN; - - /* - * With VHE (HCR.E2H == 1), accesses to CPACR_EL1 are routed to - * CPTR_EL2. In general, CPACR_EL1 has the same layout as CPTR_EL2, - * except for some missing controls, such as TAM. - * In this case, CPTR_EL2.TAM has the same position with or without - * VHE (HCR.E2H == 1) which allows us to use here the CPTR_EL2.TAM - * shift value for trapping the AMU accesses. - */ - - val |= CPTR_EL2_TAM; - - if (update_fp_enabled(vcpu)) { - if (vcpu_has_sve(vcpu)) - val |= CPACR_EL1_ZEN; - } else { - val &= ~CPACR_EL1_FPEN; - __activate_traps_fpsimd32(vcpu); - } - - write_sysreg(val, cpacr_el1); - - write_sysreg(kvm_get_hyp_vector(), vbar_el1); -} -NOKPROBE_SYMBOL(activate_traps_vhe); - -static void __hyp_text __activate_traps_nvhe(struct kvm_vcpu *vcpu) -{ - u64 val; - - __activate_traps_common(vcpu); - - val = CPTR_EL2_DEFAULT; - val |= CPTR_EL2_TTA | CPTR_EL2_TZ | CPTR_EL2_TAM; - if (!update_fp_enabled(vcpu)) { - val |= CPTR_EL2_TFP; - __activate_traps_fpsimd32(vcpu); - } - - write_sysreg(val, cptr_el2); - - if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) { - struct kvm_cpu_context *ctxt = &vcpu->arch.ctxt; - - isb(); - /* - * At this stage, and thanks to the above isb(), S2 is - * configured and enabled. We can now restore the guest's S1 - * configuration: SCTLR, and only then TCR. - */ - write_sysreg_el1(ctxt->sys_regs[SCTLR_EL1], SYS_SCTLR); - isb(); - write_sysreg_el1(ctxt->sys_regs[TCR_EL1], SYS_TCR); - } -} - -static void __hyp_text __activate_traps(struct kvm_vcpu *vcpu) -{ - u64 hcr = vcpu->arch.hcr_el2; - - if (cpus_have_final_cap(ARM64_WORKAROUND_CAVIUM_TX2_219_TVM)) - hcr |= HCR_TVM; - - write_sysreg(hcr, hcr_el2); - - if (cpus_have_final_cap(ARM64_HAS_RAS_EXTN) && (hcr & HCR_VSE)) - write_sysreg_s(vcpu->arch.vsesr_el2, SYS_VSESR_EL2); - - if (has_vhe()) - activate_traps_vhe(vcpu); - else - __activate_traps_nvhe(vcpu); -} - -static void deactivate_traps_vhe(void) -{ - extern char vectors[]; /* kernel exception vectors */ - write_sysreg(HCR_HOST_VHE_FLAGS, hcr_el2); - - /* - * ARM errata 1165522 and 1530923 require 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_SPECULATIVE_AT)); - - write_sysreg(CPACR_EL1_DEFAULT, cpacr_el1); - write_sysreg(vectors, vbar_el1); -} -NOKPROBE_SYMBOL(deactivate_traps_vhe); - -static void __hyp_text __deactivate_traps_nvhe(void) -{ - u64 mdcr_el2 = read_sysreg(mdcr_el2); - - if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) { - u64 val; - - /* - * Set the TCR and SCTLR registers in the exact opposite - * sequence as __activate_traps_nvhe (first prevent walks, - * then force the MMU on). A generous sprinkling of isb() - * ensure that things happen in this exact order. - */ - val = read_sysreg_el1(SYS_TCR); - write_sysreg_el1(val | TCR_EPD1_MASK | TCR_EPD0_MASK, SYS_TCR); - isb(); - val = read_sysreg_el1(SYS_SCTLR); - write_sysreg_el1(val | SCTLR_ELx_M, SYS_SCTLR); - isb(); - } - - __deactivate_traps_common(); - - mdcr_el2 &= MDCR_EL2_HPMN_MASK; - mdcr_el2 |= MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT; - - write_sysreg(mdcr_el2, mdcr_el2); - write_sysreg(HCR_HOST_NVHE_FLAGS, hcr_el2); - write_sysreg(CPTR_EL2_DEFAULT, cptr_el2); -} - -static void __hyp_text __deactivate_traps(struct kvm_vcpu *vcpu) -{ - /* - * If we pended a virtual abort, preserve it until it gets - * cleared. See D1.14.3 (Virtual Interrupts) for details, but - * the crucial bit is "On taking a vSError interrupt, - * HCR_EL2.VSE is cleared to 0." - */ - if (vcpu->arch.hcr_el2 & HCR_VSE) { - vcpu->arch.hcr_el2 &= ~HCR_VSE; - vcpu->arch.hcr_el2 |= read_sysreg(hcr_el2) & HCR_VSE; - } - - if (has_vhe()) - deactivate_traps_vhe(); - else - __deactivate_traps_nvhe(); -} - -void activate_traps_vhe_load(struct kvm_vcpu *vcpu) -{ - __activate_traps_common(vcpu); -} - -void deactivate_traps_vhe_put(void) -{ - u64 mdcr_el2 = read_sysreg(mdcr_el2); - - mdcr_el2 &= MDCR_EL2_HPMN_MASK | - MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT | - MDCR_EL2_TPMS; - - write_sysreg(mdcr_el2, mdcr_el2); - - __deactivate_traps_common(); -} - -static void __hyp_text __activate_vm(struct kvm *kvm) -{ - __load_guest_stage2(kvm); -} - -static void __hyp_text __deactivate_vm(struct kvm_vcpu *vcpu) -{ - write_sysreg(0, vttbr_el2); -} - -/* Save VGICv3 state on non-VHE systems */ -static void __hyp_text __hyp_vgic_save_state(struct kvm_vcpu *vcpu) -{ - if (static_branch_unlikely(&kvm_vgic_global_state.gicv3_cpuif)) { - __vgic_v3_save_state(&vcpu->arch.vgic_cpu.vgic_v3); - __vgic_v3_deactivate_traps(&vcpu->arch.vgic_cpu.vgic_v3); - } -} - -/* Restore VGICv3 state on non_VEH systems */ -static void __hyp_text __hyp_vgic_restore_state(struct kvm_vcpu *vcpu) -{ - if (static_branch_unlikely(&kvm_vgic_global_state.gicv3_cpuif)) { - __vgic_v3_activate_traps(&vcpu->arch.vgic_cpu.vgic_v3); - __vgic_v3_restore_state(&vcpu->arch.vgic_cpu.vgic_v3); - } -} - -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 & SYS_PAR_EL1_F)) - return false; /* Translation failed, back to guest */ - - /* Convert PAR to HPFAR format */ - *hpfar = PAR_TO_HPFAR(tmp); - return true; -} - -static bool __hyp_text __populate_fault_info(struct kvm_vcpu *vcpu) -{ - u8 ec; - u64 esr; - u64 hpfar, far; - - esr = vcpu->arch.fault.esr_el2; - ec = ESR_ELx_EC(esr); - - if (ec != ESR_ELx_EC_DABT_LOW && ec != ESR_ELx_EC_IABT_LOW) - return true; - - far = read_sysreg_el2(SYS_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) && - (cpus_have_final_cap(ARM64_WORKAROUND_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; -} - -/* Check for an FPSIMD/SVE trap and handle as appropriate */ -static bool __hyp_text __hyp_handle_fpsimd(struct kvm_vcpu *vcpu) -{ - bool vhe, sve_guest, sve_host; - u8 hsr_ec; - - if (!system_supports_fpsimd()) - return false; - - if (system_supports_sve()) { - sve_guest = vcpu_has_sve(vcpu); - sve_host = vcpu->arch.flags & KVM_ARM64_HOST_SVE_IN_USE; - vhe = true; - } else { - sve_guest = false; - sve_host = false; - vhe = has_vhe(); - } - - hsr_ec = kvm_vcpu_trap_get_class(vcpu); - if (hsr_ec != ESR_ELx_EC_FP_ASIMD && - hsr_ec != ESR_ELx_EC_SVE) - return false; - - /* Don't handle SVE traps for non-SVE vcpus here: */ - if (!sve_guest) - if (hsr_ec != ESR_ELx_EC_FP_ASIMD) - return false; - - /* Valid trap. Switch the context: */ - - if (vhe) { - u64 reg = read_sysreg(cpacr_el1) | CPACR_EL1_FPEN; - - if (sve_guest) - reg |= CPACR_EL1_ZEN; - - write_sysreg(reg, cpacr_el1); - } else { - write_sysreg(read_sysreg(cptr_el2) & ~(u64)CPTR_EL2_TFP, - cptr_el2); - } - - isb(); - - if (vcpu->arch.flags & KVM_ARM64_FP_HOST) { - /* - * In the SVE case, VHE is assumed: it is enforced by - * Kconfig and kvm_arch_init(). - */ - if (sve_host) { - struct thread_struct *thread = container_of( - vcpu->arch.host_fpsimd_state, - struct thread_struct, uw.fpsimd_state); - - sve_save_state(sve_pffr(thread), - &vcpu->arch.host_fpsimd_state->fpsr); - } else { - __fpsimd_save_state(vcpu->arch.host_fpsimd_state); - } - - vcpu->arch.flags &= ~KVM_ARM64_FP_HOST; - } - - if (sve_guest) { - sve_load_state(vcpu_sve_pffr(vcpu), - &vcpu->arch.ctxt.gp_regs.fp_regs.fpsr, - sve_vq_from_vl(vcpu->arch.sve_max_vl) - 1); - write_sysreg_s(vcpu->arch.ctxt.sys_regs[ZCR_EL1], SYS_ZCR_EL12); - } else { - __fpsimd_restore_state(&vcpu->arch.ctxt.gp_regs.fp_regs); - } - - /* Skip restoring fpexc32 for AArch64 guests */ - if (!(read_sysreg(hcr_el2) & HCR_RW)) - write_sysreg(vcpu->arch.ctxt.sys_regs[FPEXC32_EL2], - fpexc32_el2); - - vcpu->arch.flags |= KVM_ARM64_FP_ENABLED; - - return true; -} - -static bool __hyp_text handle_tx2_tvm(struct kvm_vcpu *vcpu) -{ - u32 sysreg = esr_sys64_to_sysreg(kvm_vcpu_get_hsr(vcpu)); - int rt = kvm_vcpu_sys_get_rt(vcpu); - u64 val = vcpu_get_reg(vcpu, rt); - - /* - * The normal sysreg handling code expects to see the traps, - * let's not do anything here. - */ - if (vcpu->arch.hcr_el2 & HCR_TVM) - return false; - - switch (sysreg) { - case SYS_SCTLR_EL1: - write_sysreg_el1(val, SYS_SCTLR); - break; - case SYS_TTBR0_EL1: - write_sysreg_el1(val, SYS_TTBR0); - break; - case SYS_TTBR1_EL1: - write_sysreg_el1(val, SYS_TTBR1); - break; - case SYS_TCR_EL1: - write_sysreg_el1(val, SYS_TCR); - break; - case SYS_ESR_EL1: - write_sysreg_el1(val, SYS_ESR); - break; - case SYS_FAR_EL1: - write_sysreg_el1(val, SYS_FAR); - break; - case SYS_AFSR0_EL1: - write_sysreg_el1(val, SYS_AFSR0); - break; - case SYS_AFSR1_EL1: - write_sysreg_el1(val, SYS_AFSR1); - break; - case SYS_MAIR_EL1: - write_sysreg_el1(val, SYS_MAIR); - break; - case SYS_AMAIR_EL1: - write_sysreg_el1(val, SYS_AMAIR); - break; - case SYS_CONTEXTIDR_EL1: - write_sysreg_el1(val, SYS_CONTEXTIDR); - break; - default: - return false; - } - - __kvm_skip_instr(vcpu); - return true; -} - -static bool __hyp_text esr_is_ptrauth_trap(u32 esr) -{ - u32 ec = ESR_ELx_EC(esr); - - if (ec == ESR_ELx_EC_PAC) - return true; - - if (ec != ESR_ELx_EC_SYS64) - return false; - - switch (esr_sys64_to_sysreg(esr)) { - case SYS_APIAKEYLO_EL1: - case SYS_APIAKEYHI_EL1: - case SYS_APIBKEYLO_EL1: - case SYS_APIBKEYHI_EL1: - case SYS_APDAKEYLO_EL1: - case SYS_APDAKEYHI_EL1: - case SYS_APDBKEYLO_EL1: - case SYS_APDBKEYHI_EL1: - case SYS_APGAKEYLO_EL1: - case SYS_APGAKEYHI_EL1: - return true; - } - - return false; -} - -#define __ptrauth_save_key(regs, key) \ -({ \ - regs[key ## KEYLO_EL1] = read_sysreg_s(SYS_ ## key ## KEYLO_EL1); \ - regs[key ## KEYHI_EL1] = read_sysreg_s(SYS_ ## key ## KEYHI_EL1); \ -}) - -static bool __hyp_text __hyp_handle_ptrauth(struct kvm_vcpu *vcpu) -{ - struct kvm_cpu_context *ctxt; - u64 val; - - if (!vcpu_has_ptrauth(vcpu) || - !esr_is_ptrauth_trap(kvm_vcpu_get_hsr(vcpu))) - return false; - - ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt; - __ptrauth_save_key(ctxt->sys_regs, APIA); - __ptrauth_save_key(ctxt->sys_regs, APIB); - __ptrauth_save_key(ctxt->sys_regs, APDA); - __ptrauth_save_key(ctxt->sys_regs, APDB); - __ptrauth_save_key(ctxt->sys_regs, APGA); - - vcpu_ptrauth_enable(vcpu); - - val = read_sysreg(hcr_el2); - val |= (HCR_API | HCR_APK); - write_sysreg(val, hcr_el2); - - return true; -} - -/* - * Return true when we were able to fixup the guest exit and should return to - * the guest, false when we should restore the host state and return to the - * main run loop. - */ -static bool __hyp_text fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code) -{ - if (ARM_EXCEPTION_CODE(*exit_code) != ARM_EXCEPTION_IRQ) - vcpu->arch.fault.esr_el2 = read_sysreg_el2(SYS_ESR); - - /* - * We're using the raw exception code in order to only process - * the trap if no SError is pending. We will come back to the - * same PC once the SError has been injected, and replay the - * trapping instruction. - */ - if (*exit_code != ARM_EXCEPTION_TRAP) - goto exit; - - if (cpus_have_final_cap(ARM64_WORKAROUND_CAVIUM_TX2_219_TVM) && - kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_SYS64 && - handle_tx2_tvm(vcpu)) - return true; - - /* - * 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. - * Similarly for trapped SVE accesses. - */ - if (__hyp_handle_fpsimd(vcpu)) - return true; - - if (__hyp_handle_ptrauth(vcpu)) - return true; - - if (!__populate_fault_info(vcpu)) - return true; - - if (static_branch_unlikely(&vgic_v2_cpuif_trap)) { - bool valid; - - valid = kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_DABT_LOW && - kvm_vcpu_trap_get_fault_type(vcpu) == FSC_FAULT && - kvm_vcpu_dabt_isvalid(vcpu) && - !kvm_vcpu_dabt_isextabt(vcpu) && - !kvm_vcpu_dabt_iss1tw(vcpu); - - if (valid) { - int ret = __vgic_v2_perform_cpuif_access(vcpu); - - if (ret == 1) - return true; - - /* Promote an illegal access to an SError.*/ - if (ret == -1) - *exit_code = ARM_EXCEPTION_EL1_SERROR; - - goto exit; - } - } - - if (static_branch_unlikely(&vgic_v3_cpuif_trap) && - (kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_SYS64 || - kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_CP15_32)) { - int ret = __vgic_v3_perform_cpuif_access(vcpu); - - if (ret == 1) - return true; - } - -exit: - /* Return to the host kernel and handle the exit */ - return false; -} - -static inline bool __hyp_text __needs_ssbd_off(struct kvm_vcpu *vcpu) -{ - if (!cpus_have_final_cap(ARM64_SSBD)) - return false; - - return !(vcpu->arch.workaround_flags & VCPU_WORKAROUND_2_FLAG); -} - -static void __hyp_text __set_guest_arch_workaround_state(struct kvm_vcpu *vcpu) -{ -#ifdef CONFIG_ARM64_SSBD - /* - * The host runs with the workaround always present. If the - * guest wants it disabled, so be it... - */ - if (__needs_ssbd_off(vcpu) && - __hyp_this_cpu_read(arm64_ssbd_callback_required)) - arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2, 0, NULL); -#endif -} - -static void __hyp_text __set_host_arch_workaround_state(struct kvm_vcpu *vcpu) -{ -#ifdef CONFIG_ARM64_SSBD - /* - * If the guest has disabled the workaround, bring it back on. - */ - if (__needs_ssbd_off(vcpu) && - __hyp_this_cpu_read(arm64_ssbd_callback_required)) - arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2, 1, NULL); -#endif -} - -/** - * Disable host events, enable guest events - */ -static bool __hyp_text __pmu_switch_to_guest(struct kvm_cpu_context *host_ctxt) -{ - struct kvm_host_data *host; - struct kvm_pmu_events *pmu; - - host = container_of(host_ctxt, struct kvm_host_data, host_ctxt); - pmu = &host->pmu_events; - - if (pmu->events_host) - write_sysreg(pmu->events_host, pmcntenclr_el0); - - if (pmu->events_guest) - write_sysreg(pmu->events_guest, pmcntenset_el0); - - return (pmu->events_host || pmu->events_guest); -} - -/** - * Disable guest events, enable host events - */ -static void __hyp_text __pmu_switch_to_host(struct kvm_cpu_context *host_ctxt) -{ - struct kvm_host_data *host; - struct kvm_pmu_events *pmu; - - host = container_of(host_ctxt, struct kvm_host_data, host_ctxt); - pmu = &host->pmu_events; - - if (pmu->events_guest) - write_sysreg(pmu->events_guest, pmcntenclr_el0); - - if (pmu->events_host) - write_sysreg(pmu->events_host, pmcntenset_el0); -} - -/* Switch to the guest for VHE systems running in EL2 */ -static int __kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu) -{ - struct kvm_cpu_context *host_ctxt; - struct kvm_cpu_context *guest_ctxt; - u64 exit_code; - - host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt; - host_ctxt->__hyp_running_vcpu = vcpu; - guest_ctxt = &vcpu->arch.ctxt; - - sysreg_save_host_state_vhe(host_ctxt); - - /* - * 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); - - __set_guest_arch_workaround_state(vcpu); - - do { - /* Jump in the fire! */ - exit_code = __guest_enter(vcpu, host_ctxt); - - /* And we're baaack! */ - } while (fixup_guest_exit(vcpu, &exit_code)); - - __set_host_arch_workaround_state(vcpu); - - sysreg_save_guest_state_vhe(guest_ctxt); - - __deactivate_traps(vcpu); - - sysreg_restore_host_state_vhe(host_ctxt); - - if (vcpu->arch.flags & KVM_ARM64_FP_ENABLED) - __fpsimd_save_fpexc32(vcpu); - - __debug_switch_to_host(vcpu); - - return exit_code; -} -NOKPROBE_SYMBOL(__kvm_vcpu_run_vhe); - -int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu) -{ - int ret; - - local_daif_mask(); - - /* - * Having IRQs masked via PMR when entering the guest means the GIC - * will not signal the CPU of interrupts of lower priority, and the - * only way to get out will be via guest exceptions. - * Naturally, we want to avoid this. - * - * local_daif_mask() already sets GIC_PRIO_PSR_I_SET, we just need a - * dsb to ensure the redistributor is forwards EL2 IRQs to the CPU. - */ - pmr_sync(); - - ret = __kvm_vcpu_run_vhe(vcpu); - - /* - * local_daif_restore() takes care to properly restore PSTATE.DAIF - * and the GIC PMR if the host is using IRQ priorities. - */ - local_daif_restore(DAIF_PROCCTX_NOIRQ); - - /* - * When we exit from the guest we change a number of CPU configuration - * parameters, such as traps. Make sure these changes take effect - * before running the host or additional guests. - */ - isb(); - - return ret; -} - -/* Switch to the guest for legacy non-VHE systems */ -int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu) -{ - struct kvm_cpu_context *host_ctxt; - struct kvm_cpu_context *guest_ctxt; - bool pmu_switch_needed; - u64 exit_code; - - /* - * Having IRQs masked via PMR when entering the guest means the GIC - * will not signal the CPU of interrupts of lower priority, and the - * only way to get out will be via guest exceptions. - * Naturally, we want to avoid this. - */ - if (system_uses_irq_prio_masking()) { - gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET); - pmr_sync(); - } - - vcpu = kern_hyp_va(vcpu); - - host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt; - host_ctxt->__hyp_running_vcpu = vcpu; - guest_ctxt = &vcpu->arch.ctxt; - - pmu_switch_needed = __pmu_switch_to_guest(host_ctxt); - - __sysreg_save_state_nvhe(host_ctxt); - - /* - * We must restore the 32-bit state before the sysregs, thanks - * to erratum #852523 (Cortex-A57) or #853709 (Cortex-A72). - * - * Also, and in order to be able to deal with erratum #1319537 (A57) - * and #1319367 (A72), we must ensure that all VM-related sysreg are - * restored before we enable S2 translation. - */ - __sysreg32_restore_state(vcpu); - __sysreg_restore_state_nvhe(guest_ctxt); - - __activate_vm(kern_hyp_va(vcpu->kvm)); - __activate_traps(vcpu); - - __hyp_vgic_restore_state(vcpu); - __timer_enable_traps(vcpu); - - __debug_switch_to_guest(vcpu); - - __set_guest_arch_workaround_state(vcpu); - - do { - /* Jump in the fire! */ - exit_code = __guest_enter(vcpu, host_ctxt); - - /* And we're baaack! */ - } while (fixup_guest_exit(vcpu, &exit_code)); - - __set_host_arch_workaround_state(vcpu); - - __sysreg_save_state_nvhe(guest_ctxt); - __sysreg32_save_state(vcpu); - __timer_disable_traps(vcpu); - __hyp_vgic_save_state(vcpu); - - __deactivate_traps(vcpu); - __deactivate_vm(vcpu); - - __sysreg_restore_state_nvhe(host_ctxt); - - if (vcpu->arch.flags & KVM_ARM64_FP_ENABLED) - __fpsimd_save_fpexc32(vcpu); - - /* - * This must come after restoring the host sysregs, since a non-VHE - * system may enable SPE here and make use of the TTBRs. - */ - __debug_switch_to_host(vcpu); - - if (pmu_switch_needed) - __pmu_switch_to_host(host_ctxt); - - /* Returning to host will clear PSR.I, remask PMR if needed */ - if (system_uses_irq_prio_masking()) - gic_write_pmr(GIC_PRIO_IRQOFF); - - return exit_code; -} - -static const char __hyp_panic_string[] = "HYP panic:\nPS:%08llx PC:%016llx ESR:%08llx\nFAR:%016llx HPFAR:%016llx PAR:%016llx\nVCPU:%p\n"; - -static void __hyp_text __hyp_call_panic_nvhe(u64 spsr, u64 elr, u64 par, - struct kvm_cpu_context *__host_ctxt) -{ - struct kvm_vcpu *vcpu; - unsigned long str_va; - - vcpu = __host_ctxt->__hyp_running_vcpu; - - if (read_sysreg(vttbr_el2)) { - __timer_disable_traps(vcpu); - __deactivate_traps(vcpu); - __deactivate_vm(vcpu); - __sysreg_restore_state_nvhe(__host_ctxt); - } - - /* - * Force the panic string to be loaded from the literal pool, - * making sure it is a kernel address and not a PC-relative - * reference. - */ - asm volatile("ldr %0, =%1" : "=r" (str_va) : "S" (__hyp_panic_string)); - - __hyp_do_panic(str_va, - spsr, elr, - read_sysreg(esr_el2), read_sysreg_el2(SYS_FAR), - read_sysreg(hpfar_el2), par, vcpu); -} - -static void __hyp_call_panic_vhe(u64 spsr, u64 elr, u64 par, - struct kvm_cpu_context *host_ctxt) -{ - struct kvm_vcpu *vcpu; - vcpu = host_ctxt->__hyp_running_vcpu; - - __deactivate_traps(vcpu); - sysreg_restore_host_state_vhe(host_ctxt); - - panic(__hyp_panic_string, - spsr, elr, - read_sysreg_el2(SYS_ESR), read_sysreg_el2(SYS_FAR), - read_sysreg(hpfar_el2), par, vcpu); -} -NOKPROBE_SYMBOL(__hyp_call_panic_vhe); - -void __hyp_text __noreturn hyp_panic(struct kvm_cpu_context *host_ctxt) -{ - u64 spsr = read_sysreg_el2(SYS_SPSR); - u64 elr = read_sysreg_el2(SYS_ELR); - u64 par = read_sysreg(par_el1); - - if (!has_vhe()) - __hyp_call_panic_nvhe(spsr, elr, par, host_ctxt); - else - __hyp_call_panic_vhe(spsr, elr, par, host_ctxt); - - unreachable(); -} diff --git a/arch/arm64/kvm/hyp/sysreg-sr.c b/arch/arm64/kvm/hyp/sysreg-sr.c index cc7e957f5b2c..2493439a5c54 100644 --- a/arch/arm64/kvm/hyp/sysreg-sr.c +++ b/arch/arm64/kvm/hyp/sysreg-sr.c @@ -114,7 +114,7 @@ static void __hyp_text __sysreg_restore_el1_state(struct kvm_cpu_context *ctxt) /* * Must only be done for guest registers, hence the context * test. We're coming from the host, so SCTLR.M is already - * set. Pairs with __activate_traps_nvhe(). + * set. Pairs with nVHE's __activate_traps(). */ write_sysreg_el1((ctxt->sys_regs[TCR_EL1] | TCR_EPD1_MASK | TCR_EPD0_MASK), @@ -142,7 +142,7 @@ static void __hyp_text __sysreg_restore_el1_state(struct kvm_cpu_context *ctxt) ctxt->__hyp_running_vcpu) { /* * Must only be done for host registers, hence the context - * test. Pairs with __deactivate_traps_nvhe(). + * test. Pairs with nVHE's __deactivate_traps(). */ isb(); /* diff --git a/arch/arm64/kvm/hyp/vhe/Makefile b/arch/arm64/kvm/hyp/vhe/Makefile index 704140fc5d66..9f71cd3ba50d 100644 --- a/arch/arm64/kvm/hyp/vhe/Makefile +++ b/arch/arm64/kvm/hyp/vhe/Makefile @@ -6,7 +6,7 @@ asflags-y := -D__KVM_VHE_HYPERVISOR__ ccflags-y := -D__KVM_VHE_HYPERVISOR__ -obj-y := tlb.o ../hyp-entry.o +obj-y := switch.o tlb.o ../hyp-entry.o # KVM code is run at a different exception code with a different map, so # compiler instrumentation that inserts callbacks or checks into the code may diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c new file mode 100644 index 000000000000..e8d76cab44e4 --- /dev/null +++ b/arch/arm64/kvm/hyp/vhe/switch.c @@ -0,0 +1,219 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2015 - ARM Ltd + * Author: Marc Zyngier <marc.zyngier@arm.com> + */ + +#include <hyp/switch.h> + +#include <linux/arm-smccc.h> +#include <linux/kvm_host.h> +#include <linux/types.h> +#include <linux/jump_label.h> +#include <uapi/linux/psci.h> + +#include <kvm/arm_psci.h> + +#include <asm/barrier.h> +#include <asm/cpufeature.h> +#include <asm/kprobes.h> +#include <asm/kvm_asm.h> +#include <asm/kvm_emulate.h> +#include <asm/kvm_hyp.h> +#include <asm/kvm_mmu.h> +#include <asm/fpsimd.h> +#include <asm/debug-monitors.h> +#include <asm/processor.h> +#include <asm/thread_info.h> + +const char __hyp_panic_string[] = "HYP panic:\nPS:%08llx PC:%016llx ESR:%08llx\nFAR:%016llx HPFAR:%016llx PAR:%016llx\nVCPU:%p\n"; + +static void __activate_traps(struct kvm_vcpu *vcpu) +{ + u64 val; + + ___activate_traps(vcpu); + + val = read_sysreg(cpacr_el1); + val |= CPACR_EL1_TTA; + val &= ~CPACR_EL1_ZEN; + + /* + * With VHE (HCR.E2H == 1), accesses to CPACR_EL1 are routed to + * CPTR_EL2. In general, CPACR_EL1 has the same layout as CPTR_EL2, + * except for some missing controls, such as TAM. + * In this case, CPTR_EL2.TAM has the same position with or without + * VHE (HCR.E2H == 1) which allows us to use here the CPTR_EL2.TAM + * shift value for trapping the AMU accesses. + */ + + val |= CPTR_EL2_TAM; + + if (update_fp_enabled(vcpu)) { + if (vcpu_has_sve(vcpu)) + val |= CPACR_EL1_ZEN; + } else { + val &= ~CPACR_EL1_FPEN; + __activate_traps_fpsimd32(vcpu); + } + + write_sysreg(val, cpacr_el1); + + write_sysreg(kvm_get_hyp_vector(), vbar_el1); +} +NOKPROBE_SYMBOL(__activate_traps); + +static void __deactivate_traps(struct kvm_vcpu *vcpu) +{ + extern char vectors[]; /* kernel exception vectors */ + + ___deactivate_traps(vcpu); + + write_sysreg(HCR_HOST_VHE_FLAGS, hcr_el2); + + /* + * ARM errata 1165522 and 1530923 require 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_SPECULATIVE_AT)); + + write_sysreg(CPACR_EL1_DEFAULT, cpacr_el1); + write_sysreg(vectors, vbar_el1); +} +NOKPROBE_SYMBOL(__deactivate_traps); + +void activate_traps_vhe_load(struct kvm_vcpu *vcpu) +{ + __activate_traps_common(vcpu); +} + +void deactivate_traps_vhe_put(void) +{ + u64 mdcr_el2 = read_sysreg(mdcr_el2); + + mdcr_el2 &= MDCR_EL2_HPMN_MASK | + MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT | + MDCR_EL2_TPMS; + + write_sysreg(mdcr_el2, mdcr_el2); + + __deactivate_traps_common(); +} + +/* Switch to the guest for VHE systems running in EL2 */ +static int __kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu) +{ + struct kvm_cpu_context *host_ctxt; + struct kvm_cpu_context *guest_ctxt; + u64 exit_code; + + host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt; + host_ctxt->__hyp_running_vcpu = vcpu; + guest_ctxt = &vcpu->arch.ctxt; + + sysreg_save_host_state_vhe(host_ctxt); + + /* + * 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); + + __set_guest_arch_workaround_state(vcpu); + + do { + /* Jump in the fire! */ + exit_code = __guest_enter(vcpu, host_ctxt); + + /* And we're baaack! */ + } while (fixup_guest_exit(vcpu, &exit_code)); + + __set_host_arch_workaround_state(vcpu); + + sysreg_save_guest_state_vhe(guest_ctxt); + + __deactivate_traps(vcpu); + + sysreg_restore_host_state_vhe(host_ctxt); + + if (vcpu->arch.flags & KVM_ARM64_FP_ENABLED) + __fpsimd_save_fpexc32(vcpu); + + __debug_switch_to_host(vcpu); + + return exit_code; +} +NOKPROBE_SYMBOL(__kvm_vcpu_run_vhe); + +int __kvm_vcpu_run(struct kvm_vcpu *vcpu) +{ + int ret; + + local_daif_mask(); + + /* + * Having IRQs masked via PMR when entering the guest means the GIC + * will not signal the CPU of interrupts of lower priority, and the + * only way to get out will be via guest exceptions. + * Naturally, we want to avoid this. + * + * local_daif_mask() already sets GIC_PRIO_PSR_I_SET, we just need a + * dsb to ensure the redistributor is forwards EL2 IRQs to the CPU. + */ + pmr_sync(); + + ret = __kvm_vcpu_run_vhe(vcpu); + + /* + * local_daif_restore() takes care to properly restore PSTATE.DAIF + * and the GIC PMR if the host is using IRQ priorities. + */ + local_daif_restore(DAIF_PROCCTX_NOIRQ); + + /* + * When we exit from the guest we change a number of CPU configuration + * parameters, such as traps. Make sure these changes take effect + * before running the host or additional guests. + */ + isb(); + + return ret; +} + +static void __hyp_call_panic(u64 spsr, u64 elr, u64 par, + struct kvm_cpu_context *host_ctxt) +{ + struct kvm_vcpu *vcpu; + vcpu = host_ctxt->__hyp_running_vcpu; + + __deactivate_traps(vcpu); + sysreg_restore_host_state_vhe(host_ctxt); + + panic(__hyp_panic_string, + spsr, elr, + read_sysreg_el2(SYS_ESR), read_sysreg_el2(SYS_FAR), + read_sysreg(hpfar_el2), par, vcpu); +} +NOKPROBE_SYMBOL(__hyp_call_panic); + +void __noreturn hyp_panic(struct kvm_cpu_context *host_ctxt) +{ + u64 spsr = read_sysreg_el2(SYS_SPSR); + u64 elr = read_sysreg_el2(SYS_ELR); + u64 par = read_sysreg(par_el1); + + __hyp_call_panic(spsr, elr, par, host_ctxt); + unreachable(); +} |