We do not have to change the c15 trap setting on each switch to/from the
guest on VHE systems, because this setting only affects EL0.
The PMU and debug trap configuration can also be done on vcpu load/put
instead, because they don't affect how the host kernel can access the
debug registers while executing KVM kernel code.
Signed-off-by: Christoffer Dall <christoffer.d...@linaro.org>
---
arch/arm64/include/asm/kvm_hyp.h | 3 +++
arch/arm64/kvm/hyp/switch.c | 31 ++++++++++++++++++++++---------
arch/arm64/kvm/hyp/sysreg-sr.c | 4 ++++
3 files changed, 29 insertions(+), 9 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h
index 2b1fda90dde4..949f2e77ae58 100644
--- a/arch/arm64/include/asm/kvm_hyp.h
+++ b/arch/arm64/include/asm/kvm_hyp.h
@@ -147,6 +147,9 @@ void __fpsimd_save_state(struct user_fpsimd_state *fp_regs);
void __fpsimd_restore_state(struct user_fpsimd_state *fp_regs);
bool __fpsimd_enabled(void);
+void activate_traps_vhe_load(struct kvm_vcpu *vcpu);
+void deactivate_traps_vhe_put(void);
+
u64 __guest_enter(struct kvm_vcpu *vcpu, struct kvm_cpu_context *host_ctxt);
void __noreturn __hyp_do_panic(unsigned long, ...);
diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index 9c40e203bd09..5e94955b89ea 100644
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -101,6 +101,8 @@ 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_TFP | CPTR_EL2_TZ;
write_sysreg(val, cptr_el2);
@@ -120,20 +122,12 @@ static void __hyp_text __activate_traps(struct kvm_vcpu
*vcpu)
write_sysreg_s(vcpu->arch.vsesr_el2, SYS_VSESR_EL2);
__activate_traps_fpsimd32(vcpu);
- __activate_traps_common(vcpu);
__activate_traps_arch()(vcpu);
}
static void __hyp_text __deactivate_traps_vhe(void)
{
extern char vectors[]; /* kernel exception vectors */
- 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);
write_sysreg(HCR_HOST_VHE_FLAGS, hcr_el2);
write_sysreg(CPACR_EL1_DEFAULT, cpacr_el1);
write_sysreg(vectors, vbar_el1);
@@ -143,6 +137,8 @@ static void __hyp_text __deactivate_traps_nvhe(void)
{
u64 mdcr_el2 = read_sysreg(mdcr_el2);
+ __deactivate_traps_common();
+
mdcr_el2 &= MDCR_EL2_HPMN_MASK;
mdcr_el2 |= MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT;
@@ -166,10 +162,27 @@ static void __hyp_text __deactivate_traps(struct kvm_vcpu
*vcpu)
if (vcpu->arch.hcr_el2 & HCR_VSE)
vcpu->arch.hcr_el2 = read_sysreg(hcr_el2);
- __deactivate_traps_common();
__deactivate_traps_arch()();
}
+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)
{
write_sysreg(kvm->arch.vttbr, vttbr_el2);
diff --git a/arch/arm64/kvm/hyp/sysreg-sr.c b/arch/arm64/kvm/hyp/sysreg-sr.c
index aacba4636871..b3894df6bf1a 100644
--- a/arch/arm64/kvm/hyp/sysreg-sr.c
+++ b/arch/arm64/kvm/hyp/sysreg-sr.c
@@ -254,6 +254,8 @@ void kvm_vcpu_load_sysregs(struct kvm_vcpu *vcpu)
__sysreg_restore_el1_state(guest_ctxt);
vcpu->arch.sysregs_loaded_on_cpu = true;
+
+ activate_traps_vhe_load(vcpu);
}
/**
@@ -275,6 +277,8 @@ void kvm_vcpu_put_sysregs(struct kvm_vcpu *vcpu)
if (!has_vhe())
return;
+ deactivate_traps_vhe_put();
+
__sysreg_save_el1_state(guest_ctxt);
__sysreg_save_user_state(guest_ctxt);
__sysreg32_save_state(vcpu);
--
2.14.2
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