[RFC PATCH v1 1/2] KVM: arm64: Use kvm_has_feat() to check if FEAT_RAS is advertised to the guest

From: Shaoqin Huang
Date: Wed Sep 25 2024 - 23:23:50 EST


Use kvm_has_feat() to check if FEAT_RAS is advertised to the guest, this
is useful when FEAT_RAS is writable.

Signed-off-by: Shaoqin Huang <shahuang@xxxxxxxxxx>
---
arch/arm64/kvm/guest.c | 4 ++--
arch/arm64/kvm/handle_exit.c | 2 +-
arch/arm64/kvm/hyp/include/hyp/switch.h | 2 +-
arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h | 7 +++++--
arch/arm64/kvm/sys_regs.c | 2 +-
5 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c
index 11098eb7eb44..938e3cd05d1e 100644
--- a/arch/arm64/kvm/guest.c
+++ b/arch/arm64/kvm/guest.c
@@ -819,7 +819,7 @@ int __kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu,
struct kvm_vcpu_events *events)
{
events->exception.serror_pending = !!(vcpu->arch.hcr_el2 & HCR_VSE);
- events->exception.serror_has_esr = cpus_have_final_cap(ARM64_HAS_RAS_EXTN);
+ events->exception.serror_has_esr = kvm_has_feat(vcpu->kvm, ID_AA64PFR0_EL1, RAS, IMP);

if (events->exception.serror_pending && events->exception.serror_has_esr)
events->exception.serror_esr = vcpu_get_vsesr(vcpu);
@@ -841,7 +841,7 @@ int __kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
bool ext_dabt_pending = events->exception.ext_dabt_pending;

if (serror_pending && has_esr) {
- if (!cpus_have_final_cap(ARM64_HAS_RAS_EXTN))
+ if (!kvm_has_feat(vcpu->kvm, ID_AA64PFR0_EL1, RAS, IMP))
return -EINVAL;

if (!((events->exception.serror_esr) & ~ESR_ELx_ISS_MASK))
diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c
index d7c2990e7c9e..99f256629ead 100644
--- a/arch/arm64/kvm/handle_exit.c
+++ b/arch/arm64/kvm/handle_exit.c
@@ -405,7 +405,7 @@ int handle_exit(struct kvm_vcpu *vcpu, int exception_index)
void handle_exit_early(struct kvm_vcpu *vcpu, int exception_index)
{
if (ARM_SERROR_PENDING(exception_index)) {
- if (this_cpu_has_cap(ARM64_HAS_RAS_EXTN)) {
+ if (kvm_has_feat(vcpu->kvm, ID_AA64PFR0_EL1, RAS, IMP)) {
u64 disr = kvm_vcpu_get_disr(vcpu);

kvm_handle_guest_serror(vcpu, disr_to_esr(disr));
diff --git a/arch/arm64/kvm/hyp/include/hyp/switch.h b/arch/arm64/kvm/hyp/include/hyp/switch.h
index 37ff87d782b6..bf176a3cc594 100644
--- a/arch/arm64/kvm/hyp/include/hyp/switch.h
+++ b/arch/arm64/kvm/hyp/include/hyp/switch.h
@@ -272,7 +272,7 @@ static inline void ___activate_traps(struct kvm_vcpu *vcpu, u64 hcr)

write_sysreg(hcr, hcr_el2);

- if (cpus_have_final_cap(ARM64_HAS_RAS_EXTN) && (hcr & HCR_VSE))
+ if (kvm_has_feat(vcpu->kvm, ID_AA64PFR0_EL1, RAS, IMP) && (hcr & HCR_VSE))
write_sysreg_s(vcpu->arch.vsesr_el2, SYS_VSESR_EL2);
}

diff --git a/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h b/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h
index 4c0fdabaf8ae..98526556d4e5 100644
--- a/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h
+++ b/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h
@@ -105,6 +105,8 @@ static inline void __sysreg_save_el1_state(struct kvm_cpu_context *ctxt)

static inline void __sysreg_save_el2_return_state(struct kvm_cpu_context *ctxt)
{
+ struct kvm_vcpu *vcpu = ctxt_to_vcpu(ctxt);
+
ctxt->regs.pc = read_sysreg_el2(SYS_ELR);
/*
* Guest PSTATE gets saved at guest fixup time in all
@@ -113,7 +115,7 @@ static inline void __sysreg_save_el2_return_state(struct kvm_cpu_context *ctxt)
if (!has_vhe() && ctxt->__hyp_running_vcpu)
ctxt->regs.pstate = read_sysreg_el2(SYS_SPSR);

- if (cpus_have_final_cap(ARM64_HAS_RAS_EXTN))
+ if (kvm_has_feat(vcpu->kvm, ID_AA64PFR0_EL1, RAS, IMP))
ctxt_sys_reg(ctxt, DISR_EL1) = read_sysreg_s(SYS_VDISR_EL2);
}

@@ -220,6 +222,7 @@ static inline void __sysreg_restore_el2_return_state(struct kvm_cpu_context *ctx
{
u64 pstate = to_hw_pstate(ctxt);
u64 mode = pstate & PSR_AA32_MODE_MASK;
+ struct kvm_vcpu *vcpu = ctxt_to_vcpu(ctxt);

/*
* Safety check to ensure we're setting the CPU up to enter the guest
@@ -238,7 +241,7 @@ static inline void __sysreg_restore_el2_return_state(struct kvm_cpu_context *ctx
write_sysreg_el2(ctxt->regs.pc, SYS_ELR);
write_sysreg_el2(pstate, SYS_SPSR);

- if (cpus_have_final_cap(ARM64_HAS_RAS_EXTN))
+ if (kvm_has_feat(vcpu->kvm, ID_AA64PFR0_EL1, RAS, IMP))
write_sysreg_s(ctxt_sys_reg(ctxt, DISR_EL1), SYS_VDISR_EL2);
}

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 31e49da867ff..b09f8ba3525b 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -4513,7 +4513,7 @@ static void vcpu_set_hcr(struct kvm_vcpu *vcpu)

if (has_vhe() || has_hvhe())
vcpu->arch.hcr_el2 |= HCR_E2H;
- if (cpus_have_final_cap(ARM64_HAS_RAS_EXTN)) {
+ if (kvm_has_feat(kvm, ID_AA64PFR0_EL1, RAS, IMP)) {
/* route synchronous external abort exceptions to EL2 */
vcpu->arch.hcr_el2 |= HCR_TEA;
/* trap error record accesses */
--
2.40.1