linux-stable/arch/arm64/kvm/hyp/include/hyp/switch.h

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// 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 <hyp/adjust_pc.h>
#include <hyp/fault.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/extable.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/kvm_nested.h>
#include <asm/fpsimd.h>
#include <asm/debug-monitors.h>
#include <asm/processor.h>
KVM: arm64: Add handler for MOPS exceptions An Armv8.8 FEAT_MOPS main or epilogue instruction will take an exception if executed on a CPU with a different MOPS implementation option (A or B) than the CPU where the preceding prologue instruction ran. In this case the OS exception handler is expected to reset the registers and restart execution from the prologue instruction. A KVM guest may use the instructions at EL1 at times when the guest is not able to handle the exception, expecting that the instructions will only run on one CPU (e.g. when running UEFI boot services in the guest). As KVM may reschedule the guest between different types of CPUs at any time (on an asymmetric system), it needs to also handle the resulting exception itself in case the guest is not able to. A similar situation will also occur in the future when live migrating a guest from one type of CPU to another. Add handling for the MOPS exception to KVM. The handling can be shared with the EL0 exception handler, as the logic and register layouts are the same. The exception can be handled right after exiting a guest, which avoids the cost of returning to the host exit handler. Similarly to the EL0 exception handler, in case the main or epilogue instruction is being single stepped, it makes sense to finish the step before executing the prologue instruction, so advance the single step state machine. Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230922112508.1774352-2-kristina.martsenko@arm.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-09-22 11:25:07 +00:00
#include <asm/traps.h>
struct kvm_exception_table_entry {
int insn, fixup;
};
extern struct kvm_exception_table_entry __start___kvm_ex_table;
extern struct kvm_exception_table_entry __stop___kvm_ex_table;
/* Check whether the FP regs are owned by the guest */
static inline bool guest_owns_fp_regs(struct kvm_vcpu *vcpu)
{
return vcpu->arch.fp_state == FP_STATE_GUEST_OWNED;
}
/* Save the 32-bit only FPSIMD system register state */
static inline void __fpsimd_save_fpexc32(struct kvm_vcpu *vcpu)
{
if (!vcpu_el1_is_32bit(vcpu))
return;
__vcpu_sys_reg(vcpu, FPEXC32_EL2) = read_sysreg(fpexc32_el2);
}
static inline void __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();
}
}
#define compute_clr_set(vcpu, reg, clr, set) \
do { \
u64 hfg; \
hfg = __vcpu_sys_reg(vcpu, reg) & ~__ ## reg ## _RES0; \
set |= hfg & __ ## reg ## _MASK; \
clr |= ~hfg & __ ## reg ## _nMASK; \
} while(0)
#define reg_to_fgt_group_id(reg) \
({ \
enum fgt_group_id id; \
switch(reg) { \
case HFGRTR_EL2: \
case HFGWTR_EL2: \
id = HFGxTR_GROUP; \
break; \
case HFGITR_EL2: \
id = HFGITR_GROUP; \
break; \
case HDFGRTR_EL2: \
case HDFGWTR_EL2: \
id = HDFGRTR_GROUP; \
break; \
case HAFGRTR_EL2: \
id = HAFGRTR_GROUP; \
break; \
default: \
BUILD_BUG_ON(1); \
} \
\
id; \
})
#define compute_undef_clr_set(vcpu, kvm, reg, clr, set) \
do { \
u64 hfg = kvm->arch.fgu[reg_to_fgt_group_id(reg)]; \
set |= hfg & __ ## reg ## _MASK; \
clr |= hfg & __ ## reg ## _nMASK; \
} while(0)
#define update_fgt_traps_cs(hctxt, vcpu, kvm, reg, clr, set) \
do { \
u64 c = 0, s = 0; \
\
ctxt_sys_reg(hctxt, reg) = read_sysreg_s(SYS_ ## reg); \
if (vcpu_has_nv(vcpu) && !is_hyp_ctxt(vcpu)) \
compute_clr_set(vcpu, reg, c, s); \
\
compute_undef_clr_set(vcpu, kvm, reg, c, s); \
\
s |= set; \
c |= clr; \
if (c || s) { \
u64 val = __ ## reg ## _nMASK; \
val |= s; \
val &= ~c; \
write_sysreg_s(val, SYS_ ## reg); \
} \
} while(0)
#define update_fgt_traps(hctxt, vcpu, kvm, reg) \
update_fgt_traps_cs(hctxt, vcpu, kvm, reg, 0, 0)
/*
* Validate the fine grain trap masks.
* Check that the masks do not overlap and that all bits are accounted for.
*/
#define CHECK_FGT_MASKS(reg) \
do { \
BUILD_BUG_ON((__ ## reg ## _MASK) & (__ ## reg ## _nMASK)); \
BUILD_BUG_ON(~((__ ## reg ## _RES0) ^ (__ ## reg ## _MASK) ^ \
(__ ## reg ## _nMASK))); \
} while(0)
static inline bool cpu_has_amu(void)
{
u64 pfr0 = read_sysreg_s(SYS_ID_AA64PFR0_EL1);
return cpuid_feature_extract_unsigned_field(pfr0,
ID_AA64PFR0_EL1_AMU_SHIFT);
}
static inline void __activate_traps_hfgxtr(struct kvm_vcpu *vcpu)
{
struct kvm_cpu_context *hctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
struct kvm *kvm = kern_hyp_va(vcpu->kvm);
CHECK_FGT_MASKS(HFGRTR_EL2);
CHECK_FGT_MASKS(HFGWTR_EL2);
CHECK_FGT_MASKS(HFGITR_EL2);
CHECK_FGT_MASKS(HDFGRTR_EL2);
CHECK_FGT_MASKS(HDFGWTR_EL2);
CHECK_FGT_MASKS(HAFGRTR_EL2);
CHECK_FGT_MASKS(HCRX_EL2);
if (!cpus_have_final_cap(ARM64_HAS_FGT))
return;
update_fgt_traps(hctxt, vcpu, kvm, HFGRTR_EL2);
update_fgt_traps_cs(hctxt, vcpu, kvm, HFGWTR_EL2, 0,
cpus_have_final_cap(ARM64_WORKAROUND_AMPERE_AC03_CPU_38) ?
HFGxTR_EL2_TCR_EL1_MASK : 0);
update_fgt_traps(hctxt, vcpu, kvm, HFGITR_EL2);
update_fgt_traps(hctxt, vcpu, kvm, HDFGRTR_EL2);
update_fgt_traps(hctxt, vcpu, kvm, HDFGWTR_EL2);
if (cpu_has_amu())
update_fgt_traps(hctxt, vcpu, kvm, HAFGRTR_EL2);
}
#define __deactivate_fgt(htcxt, vcpu, kvm, reg) \
do { \
if ((vcpu_has_nv(vcpu) && !is_hyp_ctxt(vcpu)) || \
kvm->arch.fgu[reg_to_fgt_group_id(reg)]) \
write_sysreg_s(ctxt_sys_reg(hctxt, reg), \
SYS_ ## reg); \
} while(0)
static inline void __deactivate_traps_hfgxtr(struct kvm_vcpu *vcpu)
{
struct kvm_cpu_context *hctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
struct kvm *kvm = kern_hyp_va(vcpu->kvm);
if (!cpus_have_final_cap(ARM64_HAS_FGT))
return;
__deactivate_fgt(hctxt, vcpu, kvm, HFGRTR_EL2);
if (cpus_have_final_cap(ARM64_WORKAROUND_AMPERE_AC03_CPU_38))
write_sysreg_s(ctxt_sys_reg(hctxt, HFGWTR_EL2), SYS_HFGWTR_EL2);
else
__deactivate_fgt(hctxt, vcpu, kvm, HFGWTR_EL2);
__deactivate_fgt(hctxt, vcpu, kvm, HFGITR_EL2);
__deactivate_fgt(hctxt, vcpu, kvm, HDFGRTR_EL2);
__deactivate_fgt(hctxt, vcpu, kvm, HDFGWTR_EL2);
if (cpu_has_amu())
__deactivate_fgt(hctxt, vcpu, kvm, HAFGRTR_EL2);
}
static inline void __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.
*/
if (kvm_arm_support_pmu_v3()) {
struct kvm_cpu_context *hctxt;
write_sysreg(0, pmselr_el0);
hctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
ctxt_sys_reg(hctxt, PMUSERENR_EL0) = read_sysreg(pmuserenr_el0);
write_sysreg(ARMV8_PMU_USERENR_MASK, pmuserenr_el0);
vcpu_set_flag(vcpu, PMUSERENR_ON_CPU);
}
vcpu->arch.mdcr_el2_host = read_sysreg(mdcr_el2);
write_sysreg(vcpu->arch.mdcr_el2, mdcr_el2);
if (cpus_have_final_cap(ARM64_HAS_HCX)) {
u64 hcrx = vcpu->arch.hcrx_el2;
if (vcpu_has_nv(vcpu) && !is_hyp_ctxt(vcpu)) {
u64 clr = 0, set = 0;
compute_clr_set(vcpu, HCRX_EL2, clr, set);
hcrx |= set;
hcrx &= ~clr;
}
write_sysreg_s(hcrx, SYS_HCRX_EL2);
}
__activate_traps_hfgxtr(vcpu);
}
static inline void __deactivate_traps_common(struct kvm_vcpu *vcpu)
{
write_sysreg(vcpu->arch.mdcr_el2_host, mdcr_el2);
write_sysreg(0, hstr_el2);
if (kvm_arm_support_pmu_v3()) {
struct kvm_cpu_context *hctxt;
hctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
write_sysreg(ctxt_sys_reg(hctxt, PMUSERENR_EL0), pmuserenr_el0);
vcpu_clear_flag(vcpu, PMUSERENR_ON_CPU);
}
if (cpus_have_final_cap(ARM64_HAS_HCX))
write_sysreg_s(HCRX_HOST_FLAGS, SYS_HCRX_EL2);
__deactivate_traps_hfgxtr(vcpu);
}
static inline void ___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 ___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 bool __populate_fault_info(struct kvm_vcpu *vcpu)
{
return __get_fault_info(vcpu->arch.fault.esr_el2, &vcpu->arch.fault);
}
KVM: arm64: Add handler for MOPS exceptions An Armv8.8 FEAT_MOPS main or epilogue instruction will take an exception if executed on a CPU with a different MOPS implementation option (A or B) than the CPU where the preceding prologue instruction ran. In this case the OS exception handler is expected to reset the registers and restart execution from the prologue instruction. A KVM guest may use the instructions at EL1 at times when the guest is not able to handle the exception, expecting that the instructions will only run on one CPU (e.g. when running UEFI boot services in the guest). As KVM may reschedule the guest between different types of CPUs at any time (on an asymmetric system), it needs to also handle the resulting exception itself in case the guest is not able to. A similar situation will also occur in the future when live migrating a guest from one type of CPU to another. Add handling for the MOPS exception to KVM. The handling can be shared with the EL0 exception handler, as the logic and register layouts are the same. The exception can be handled right after exiting a guest, which avoids the cost of returning to the host exit handler. Similarly to the EL0 exception handler, in case the main or epilogue instruction is being single stepped, it makes sense to finish the step before executing the prologue instruction, so advance the single step state machine. Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20230922112508.1774352-2-kristina.martsenko@arm.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-09-22 11:25:07 +00:00
static bool kvm_hyp_handle_mops(struct kvm_vcpu *vcpu, u64 *exit_code)
{
*vcpu_pc(vcpu) = read_sysreg_el2(SYS_ELR);
arm64_mops_reset_regs(vcpu_gp_regs(vcpu), vcpu->arch.fault.esr_el2);
write_sysreg_el2(*vcpu_pc(vcpu), SYS_ELR);
/*
* Finish potential single step before executing the prologue
* instruction.
*/
*vcpu_cpsr(vcpu) &= ~DBG_SPSR_SS;
write_sysreg_el2(*vcpu_cpsr(vcpu), SYS_SPSR);
return true;
}
static inline void __hyp_sve_restore_guest(struct kvm_vcpu *vcpu)
{
sve_cond_update_zcr_vq(vcpu_sve_max_vq(vcpu) - 1, SYS_ZCR_EL2);
__sve_restore_state(vcpu_sve_pffr(vcpu),
&vcpu->arch.ctxt.fp_regs.fpsr);
write_sysreg_el1(__vcpu_sys_reg(vcpu, ZCR_EL1), SYS_ZCR);
}
/*
* 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.
*/
static bool kvm_hyp_handle_fpsimd(struct kvm_vcpu *vcpu, u64 *exit_code)
{
bool sve_guest;
u8 esr_ec;
u64 reg;
if (!system_supports_fpsimd())
return false;
sve_guest = vcpu_has_sve(vcpu);
esr_ec = kvm_vcpu_trap_get_class(vcpu);
/* Only handle traps the vCPU can support here: */
switch (esr_ec) {
case ESR_ELx_EC_FP_ASIMD:
break;
case ESR_ELx_EC_SVE:
if (!sve_guest)
return false;
break;
default:
return false;
}
/* Valid trap. Switch the context: */
/* First disable enough traps to allow us to update the registers */
if (has_vhe() || has_hvhe()) {
reg = CPACR_EL1_FPEN_EL0EN | CPACR_EL1_FPEN_EL1EN;
if (sve_guest)
reg |= CPACR_EL1_ZEN_EL0EN | CPACR_EL1_ZEN_EL1EN;
sysreg_clear_set(cpacr_el1, 0, reg);
} else {
reg = CPTR_EL2_TFP;
if (sve_guest)
reg |= CPTR_EL2_TZ;
sysreg_clear_set(cptr_el2, reg, 0);
}
isb();
/* Write out the host state if it's in the registers */
if (vcpu->arch.fp_state == FP_STATE_HOST_OWNED)
__fpsimd_save_state(vcpu->arch.host_fpsimd_state);
/* Restore the guest state */
if (sve_guest)
__hyp_sve_restore_guest(vcpu);
else
__fpsimd_restore_state(&vcpu->arch.ctxt.fp_regs);
/* Skip restoring fpexc32 for AArch64 guests */
if (!(read_sysreg(hcr_el2) & HCR_RW))
write_sysreg(__vcpu_sys_reg(vcpu, FPEXC32_EL2), fpexc32_el2);
vcpu->arch.fp_state = FP_STATE_GUEST_OWNED;
return true;
}
static inline bool handle_tx2_tvm(struct kvm_vcpu *vcpu)
{
u32 sysreg = esr_sys64_to_sysreg(kvm_vcpu_get_esr(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 esr_is_ptrauth_trap(u64 esr)
{
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(ctxt, key) \
do { \
u64 __val; \
__val = read_sysreg_s(SYS_ ## key ## KEYLO_EL1); \
ctxt_sys_reg(ctxt, key ## KEYLO_EL1) = __val; \
__val = read_sysreg_s(SYS_ ## key ## KEYHI_EL1); \
ctxt_sys_reg(ctxt, key ## KEYHI_EL1) = __val; \
} while(0)
DECLARE_PER_CPU(struct kvm_cpu_context, kvm_hyp_ctxt);
static bool kvm_hyp_handle_ptrauth(struct kvm_vcpu *vcpu, u64 *exit_code)
{
struct kvm_cpu_context *ctxt;
u64 val;
if (!vcpu_has_ptrauth(vcpu))
return false;
ctxt = this_cpu_ptr(&kvm_hyp_ctxt);
__ptrauth_save_key(ctxt, APIA);
__ptrauth_save_key(ctxt, APIB);
__ptrauth_save_key(ctxt, APDA);
__ptrauth_save_key(ctxt, APDB);
__ptrauth_save_key(ctxt, APGA);
vcpu_ptrauth_enable(vcpu);
val = read_sysreg(hcr_el2);
val |= (HCR_API | HCR_APK);
write_sysreg(val, hcr_el2);
return true;
}
static bool kvm_hyp_handle_cntpct(struct kvm_vcpu *vcpu)
{
struct arch_timer_context *ctxt;
u32 sysreg;
u64 val;
/*
* We only get here for 64bit guests, 32bit guests will hit
* the long and winding road all the way to the standard
* handling. Yes, it sucks to be irrelevant.
*/
sysreg = esr_sys64_to_sysreg(kvm_vcpu_get_esr(vcpu));
switch (sysreg) {
case SYS_CNTPCT_EL0:
case SYS_CNTPCTSS_EL0:
if (vcpu_has_nv(vcpu)) {
if (is_hyp_ctxt(vcpu)) {
ctxt = vcpu_hptimer(vcpu);
break;
}
/* Check for guest hypervisor trapping */
val = __vcpu_sys_reg(vcpu, CNTHCTL_EL2);
if (!vcpu_el2_e2h_is_set(vcpu))
val = (val & CNTHCTL_EL1PCTEN) << 10;
if (!(val & (CNTHCTL_EL1PCTEN << 10)))
return false;
}
ctxt = vcpu_ptimer(vcpu);
break;
default:
return false;
}
val = arch_timer_read_cntpct_el0();
if (ctxt->offset.vm_offset)
val -= *kern_hyp_va(ctxt->offset.vm_offset);
if (ctxt->offset.vcpu_offset)
val -= *kern_hyp_va(ctxt->offset.vcpu_offset);
vcpu_set_reg(vcpu, kvm_vcpu_sys_get_rt(vcpu), val);
__kvm_skip_instr(vcpu);
return true;
}
static bool handle_ampere1_tcr(struct kvm_vcpu *vcpu)
{
u32 sysreg = esr_sys64_to_sysreg(kvm_vcpu_get_esr(vcpu));
int rt = kvm_vcpu_sys_get_rt(vcpu);
u64 val = vcpu_get_reg(vcpu, rt);
if (sysreg != SYS_TCR_EL1)
return false;
/*
* Affected parts do not advertise support for hardware Access Flag /
* Dirty state management in ID_AA64MMFR1_EL1.HAFDBS, but the underlying
* control bits are still functional. The architecture requires these be
* RES0 on systems that do not implement FEAT_HAFDBS.
*
* Uphold the requirements of the architecture by masking guest writes
* to TCR_EL1.{HA,HD} here.
*/
val &= ~(TCR_HD | TCR_HA);
write_sysreg_el1(val, SYS_TCR);
__kvm_skip_instr(vcpu);
return true;
}
static bool kvm_hyp_handle_sysreg(struct kvm_vcpu *vcpu, u64 *exit_code)
{
if (cpus_have_final_cap(ARM64_WORKAROUND_CAVIUM_TX2_219_TVM) &&
handle_tx2_tvm(vcpu))
return true;
if (cpus_have_final_cap(ARM64_WORKAROUND_AMPERE_AC03_CPU_38) &&
handle_ampere1_tcr(vcpu))
return true;
if (static_branch_unlikely(&vgic_v3_cpuif_trap) &&
__vgic_v3_perform_cpuif_access(vcpu) == 1)
return true;
if (esr_is_ptrauth_trap(kvm_vcpu_get_esr(vcpu)))
return kvm_hyp_handle_ptrauth(vcpu, exit_code);
if (kvm_hyp_handle_cntpct(vcpu))
return true;
return false;
}
static bool kvm_hyp_handle_cp15_32(struct kvm_vcpu *vcpu, u64 *exit_code)
{
if (static_branch_unlikely(&vgic_v3_cpuif_trap) &&
__vgic_v3_perform_cpuif_access(vcpu) == 1)
return true;
return false;
}
static bool kvm_hyp_handle_memory_fault(struct kvm_vcpu *vcpu, u64 *exit_code)
{
if (!__populate_fault_info(vcpu))
return true;
return false;
}
static bool kvm_hyp_handle_iabt_low(struct kvm_vcpu *vcpu, u64 *exit_code)
__alias(kvm_hyp_handle_memory_fault);
static bool kvm_hyp_handle_watchpt_low(struct kvm_vcpu *vcpu, u64 *exit_code)
__alias(kvm_hyp_handle_memory_fault);
static bool kvm_hyp_handle_dabt_low(struct kvm_vcpu *vcpu, u64 *exit_code)
{
if (kvm_hyp_handle_memory_fault(vcpu, exit_code))
return true;
if (static_branch_unlikely(&vgic_v2_cpuif_trap)) {
bool valid;
valid = kvm_vcpu_trap_is_translation_fault(vcpu) &&
kvm_vcpu_dabt_isvalid(vcpu) &&
!kvm_vcpu_abt_issea(vcpu) &&
!kvm_vcpu_abt_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;
}
}
return false;
}
typedef bool (*exit_handler_fn)(struct kvm_vcpu *, u64 *);
static const exit_handler_fn *kvm_get_exit_handler_array(struct kvm_vcpu *vcpu);
static void early_exit_filter(struct kvm_vcpu *vcpu, u64 *exit_code);
/*
* Allow the hypervisor to handle the exit with an exit handler if it has one.
*
* Returns true if the hypervisor handled the exit, and control should go back
* to the guest, or false if it hasn't.
*/
static inline bool kvm_hyp_handle_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
{
const exit_handler_fn *handlers = kvm_get_exit_handler_array(vcpu);
exit_handler_fn fn;
fn = handlers[kvm_vcpu_trap_get_class(vcpu)];
if (fn)
return fn(vcpu, exit_code);
return false;
}
static inline void synchronize_vcpu_pstate(struct kvm_vcpu *vcpu, u64 *exit_code)
{
/*
* Check for the conditions of Cortex-A510's #2077057. When these occur
* SPSR_EL2 can't be trusted, but isn't needed either as it is
* unchanged from the value in vcpu_gp_regs(vcpu)->pstate.
* Are we single-stepping the guest, and took a PAC exception from the
* active-not-pending state?
*/
if (cpus_have_final_cap(ARM64_WORKAROUND_2077057) &&
vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP &&
*vcpu_cpsr(vcpu) & DBG_SPSR_SS &&
ESR_ELx_EC(read_sysreg_el2(SYS_ESR)) == ESR_ELx_EC_PAC)
write_sysreg_el2(*vcpu_cpsr(vcpu), SYS_SPSR);
vcpu->arch.ctxt.regs.pstate = read_sysreg_el2(SYS_SPSR);
}
/*
* 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 fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
{
/*
* Save PSTATE early so that we can evaluate the vcpu mode
* early on.
*/
synchronize_vcpu_pstate(vcpu, exit_code);
/*
* Check whether we want to repaint the state one way or
* another.
*/
early_exit_filter(vcpu, exit_code);
if (ARM_EXCEPTION_CODE(*exit_code) != ARM_EXCEPTION_IRQ)
vcpu->arch.fault.esr_el2 = read_sysreg_el2(SYS_ESR);
if (ARM_SERROR_PENDING(*exit_code) &&
ARM_EXCEPTION_CODE(*exit_code) != ARM_EXCEPTION_IRQ) {
u8 esr_ec = kvm_vcpu_trap_get_class(vcpu);
/*
* HVC already have an adjusted PC, which we need to
* correct in order to return to after having injected
* the SError.
*
* SMC, on the other hand, is *trapped*, meaning its
* preferred return address is the SMC itself.
*/
if (esr_ec == ESR_ELx_EC_HVC32 || esr_ec == ESR_ELx_EC_HVC64)
write_sysreg_el2(read_sysreg_el2(SYS_ELR) - 4, SYS_ELR);
}
/*
* 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;
/* Check if there's an exit handler and allow it to handle the exit. */
if (kvm_hyp_handle_exit(vcpu, exit_code))
goto guest;
exit:
/* Return to the host kernel and handle the exit */
return false;
guest:
/* Re-enter the guest */
asm(ALTERNATIVE("nop", "dmb sy", ARM64_WORKAROUND_1508412));
return true;
}
static inline void __kvm_unexpected_el2_exception(void)
{
extern char __guest_exit_panic[];
unsigned long addr, fixup;
struct kvm_exception_table_entry *entry, *end;
unsigned long elr_el2 = read_sysreg(elr_el2);
entry = &__start___kvm_ex_table;
end = &__stop___kvm_ex_table;
while (entry < end) {
addr = (unsigned long)&entry->insn + entry->insn;
fixup = (unsigned long)&entry->fixup + entry->fixup;
if (addr != elr_el2) {
entry++;
continue;
}
write_sysreg(fixup, elr_el2);
return;
}
/* Trigger a panic after restoring the hyp context. */
write_sysreg(__guest_exit_panic, elr_el2);
}
#endif /* __ARM64_KVM_HYP_SWITCH_H__ */