From: Marc Zyngier <maz@xxxxxxxxxx>
Naturally, a change to the VMID for an MMU implies a new value for
VTTBR. Reload on VMID change in anticipation of loading stage-2 on
vcpu_load() instead of every guest entry.
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
Signed-off-by: Oliver Upton <oliver.upton@xxxxxxxxx>
---
arch/arm64/include/asm/kvm_host.h | 2 +-
arch/arm64/kvm/arm.c | 5 ++++-
arch/arm64/kvm/vmid.c | 11 ++++++++---
3 files changed, 13 insertions(+), 5 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index af06ccb7ee34..be0ab101c557 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -1025,7 +1025,7 @@ int kvm_arm_pvtime_has_attr(struct kvm_vcpu *vcpu,
extern unsigned int __ro_after_init kvm_arm_vmid_bits;
int __init kvm_arm_vmid_alloc_init(void);
void __init kvm_arm_vmid_alloc_free(void);
-void kvm_arm_vmid_update(struct kvm_vmid *kvm_vmid);
+bool kvm_arm_vmid_update(struct kvm_vmid *kvm_vmid);
void kvm_arm_vmid_clear_active(void);
static inline void kvm_arm_pvtime_vcpu_init(struct kvm_vcpu_arch *vcpu_arch)
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 4866b3f7b4ea..3ab904adbd64 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -950,7 +950,10 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
* making a thread's VMID inactive. So we need to call
* kvm_arm_vmid_update() in non-premptible context.
*/
- kvm_arm_vmid_update(&vcpu->arch.hw_mmu->vmid);
+ if (kvm_arm_vmid_update(&vcpu->arch.hw_mmu->vmid) &&
+ has_vhe())
+ __load_stage2(vcpu->arch.hw_mmu,
+ vcpu->arch.hw_mmu->arch);
kvm_pmu_flush_hwstate(vcpu);
diff --git a/arch/arm64/kvm/vmid.c b/arch/arm64/kvm/vmid.c
index 7fe8ba1a2851..806223b7022a 100644
--- a/arch/arm64/kvm/vmid.c
+++ b/arch/arm64/kvm/vmid.c
@@ -135,10 +135,11 @@ void kvm_arm_vmid_clear_active(void)
atomic64_set(this_cpu_ptr(&active_vmids), VMID_ACTIVE_INVALID);
}
-void kvm_arm_vmid_update(struct kvm_vmid *kvm_vmid)
+bool kvm_arm_vmid_update(struct kvm_vmid *kvm_vmid)
{
unsigned long flags;
u64 vmid, old_active_vmid;
+ bool updated = false;
vmid = atomic64_read(&kvm_vmid->id);
@@ -156,17 +157,21 @@ void kvm_arm_vmid_update(struct kvm_vmid *kvm_vmid)
if (old_active_vmid != 0 && vmid_gen_match(vmid) &&
0 != atomic64_cmpxchg_relaxed(this_cpu_ptr(&active_vmids),
old_active_vmid, vmid))
- return;
+ return false;
raw_spin_lock_irqsave(&cpu_vmid_lock, flags);
/* Check that our VMID belongs to the current generation. */
vmid = atomic64_read(&kvm_vmid->id);
- if (!vmid_gen_match(vmid))
+ if (!vmid_gen_match(vmid)) {
vmid = new_vmid(kvm_vmid);
+ updated = true;
+ }
atomic64_set(this_cpu_ptr(&active_vmids), vmid);
raw_spin_unlock_irqrestore(&cpu_vmid_lock, flags);
+
+ return updated;
}
/*
--
2.42.0.655.g421f12c284-goog
