Re: [PATCH v2 16/43] KVM: arm64: Support timers in realm RECs

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 12/04/2024 09:42, Steven Price wrote:
The RMM keeps track of the timer while the realm REC is running, but on
exit to the normal world KVM is responsible for handling the timers.


minor nit: It may be worth mentioning this will be hooked in, when we
add the Realm exit handling.

Otherwise looks good to me.


Suzuki


Signed-off-by: Steven Price <steven.price@xxxxxxx>
---
  arch/arm64/kvm/arch_timer.c  | 45 ++++++++++++++++++++++++++++++++----
  include/kvm/arm_arch_timer.h |  2 ++
  2 files changed, 43 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/kvm/arch_timer.c b/arch/arm64/kvm/arch_timer.c
index 879982b1cc73..0b2be34a9ba3 100644
--- a/arch/arm64/kvm/arch_timer.c
+++ b/arch/arm64/kvm/arch_timer.c
@@ -162,6 +162,13 @@ static void timer_set_cval(struct arch_timer_context *ctxt, u64 cval)
static void timer_set_offset(struct arch_timer_context *ctxt, u64 offset)
  {
+	struct kvm_vcpu *vcpu = ctxt->vcpu;
+
+	if (kvm_is_realm(vcpu->kvm)) {
+		WARN_ON(offset);
+		return;
+	}
+
  	if (!ctxt->offset.vm_offset) {
  		WARN(offset, "timer %ld\n", arch_timer_ctx_index(ctxt));
  		return;
@@ -460,6 +467,21 @@ static void kvm_timer_update_irq(struct kvm_vcpu *vcpu, bool new_level,
  	}
  }
+void kvm_realm_timers_update(struct kvm_vcpu *vcpu)
+{
+	struct arch_timer_cpu *arch_timer = &vcpu->arch.timer_cpu;
+	int i;
+
+	for (i = 0; i < NR_KVM_EL0_TIMERS; i++) {
+		struct arch_timer_context *timer = &arch_timer->timers[i];
+		bool status = timer_get_ctl(timer) & ARCH_TIMER_CTRL_IT_STAT;
+		bool level = kvm_timer_irq_can_fire(timer) && status;
+
+		if (level != timer->irq.level)
+			kvm_timer_update_irq(vcpu, level, timer);
+	}
+}
+
  /* Only called for a fully emulated timer */
  static void timer_emulate(struct arch_timer_context *ctx)
  {
@@ -831,6 +853,8 @@ void kvm_timer_vcpu_load(struct kvm_vcpu *vcpu)
  	if (unlikely(!timer->enabled))
  		return;
+ kvm_timer_unblocking(vcpu);
+
  	get_timer_map(vcpu, &map);
if (static_branch_likely(&has_gic_active_state)) {
@@ -844,8 +868,6 @@ void kvm_timer_vcpu_load(struct kvm_vcpu *vcpu)
  		kvm_timer_vcpu_load_nogic(vcpu);
  	}
- kvm_timer_unblocking(vcpu);
-
  	timer_restore_state(map.direct_vtimer);
  	if (map.direct_ptimer)
  		timer_restore_state(map.direct_ptimer);
@@ -988,7 +1010,9 @@ static void timer_context_init(struct kvm_vcpu *vcpu, int timerid)
ctxt->vcpu = vcpu; - if (timerid == TIMER_VTIMER)
+	if (kvm_is_realm(vcpu->kvm))
+		ctxt->offset.vm_offset = NULL;
+	else if (timerid == TIMER_VTIMER)
  		ctxt->offset.vm_offset = &kvm->arch.timer_data.voffset;
  	else
  		ctxt->offset.vm_offset = &kvm->arch.timer_data.poffset;
@@ -1011,13 +1035,19 @@ static void timer_context_init(struct kvm_vcpu *vcpu, int timerid)
  void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu)
  {
  	struct arch_timer_cpu *timer = vcpu_timer(vcpu);
+	u64 cntvoff;
for (int i = 0; i < NR_KVM_TIMERS; i++)
  		timer_context_init(vcpu, i);
+ if (kvm_is_realm(vcpu->kvm))
+		cntvoff = 0;
+	else
+		cntvoff = kvm_phys_timer_read();
+
  	/* Synchronize offsets across timers of a VM if not already provided */
  	if (!test_bit(KVM_ARCH_FLAG_VM_COUNTER_OFFSET, &vcpu->kvm->arch.flags)) {
-		timer_set_offset(vcpu_vtimer(vcpu), kvm_phys_timer_read());
+		timer_set_offset(vcpu_vtimer(vcpu), cntvoff);
  		timer_set_offset(vcpu_ptimer(vcpu), 0);
  	}
@@ -1525,6 +1555,13 @@ int kvm_timer_enable(struct kvm_vcpu *vcpu)
  		return -EINVAL;
  	}
+ /*
+	 * We don't use mapped IRQs for Realms because the RMI doesn't allow
+	 * us setting the LR.HW bit in the VGIC.
+	 */
+	if (vcpu_is_rec(vcpu))
+		return 0;
+
  	get_timer_map(vcpu, &map);
ret = kvm_vgic_map_phys_irq(vcpu,
diff --git a/include/kvm/arm_arch_timer.h b/include/kvm/arm_arch_timer.h
index c819c5d16613..d8ab297560d0 100644
--- a/include/kvm/arm_arch_timer.h
+++ b/include/kvm/arm_arch_timer.h
@@ -112,6 +112,8 @@ int kvm_arm_timer_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr);
  int kvm_arm_timer_get_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr);
  int kvm_arm_timer_has_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr);
+void kvm_realm_timers_update(struct kvm_vcpu *vcpu);
+
  u64 kvm_phys_timer_read(void);
void kvm_timer_vcpu_load(struct kvm_vcpu *vcpu);





[Index of Archives]     [KVM ARM]     [KVM ia64]     [KVM ppc]     [Virtualization Tools]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite Questions]     [Linux Kernel]     [Linux SCSI]     [XFree86]

  Powered by Linux