blob: db1c4487d95d17d18d3e2b92b15bf2d21920be78 [file] [log] [blame]
// 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, =__hyp_panic_string" : "=r" (str_va));
__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();
}