Use vcpu_data.pi_desc_addr instead of amd_iommu_pi_data.base to get the
GA root pointer. KVM is the only source of amd_iommu_pi_data.base, and
KVM's one and only path for writing amd_iommu_pi_data.base computes the
exact same value for vcpu_data.pi_desc_addr and amd_iommu_pi_data.base,
and fills amd_iommu_pi_data.base if and only if vcpu_data.pi_desc_addr is
valid, i.e. amd_iommu_pi_data.base is fully redundant.
Cc: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
Reviewed-by: Joao Martins <joao.m.martins@xxxxxxxxxx>
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/kvm/svm/avic.c | 7 +++++--
drivers/iommu/amd/iommu.c | 2 +-
include/linux/amd-iommu.h | 1 -
3 files changed, 6 insertions(+), 4 deletions(-)
diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c
index 60e6e82fe41f..9024b9fbca53 100644
--- a/arch/x86/kvm/svm/avic.c
+++ b/arch/x86/kvm/svm/avic.c
@@ -902,8 +902,11 @@ int avic_pi_update_irte(struct kvm_kernel_irqfd *irqfd, struct kvm *kvm,
enable_remapped_mode = false;
- /* Try to enable guest_mode in IRTE */
- pi.base = avic_get_backing_page_address(svm);
+ /*
+ * Try to enable guest_mode in IRTE. Note, the address
+ * of the vCPU's AVIC backing page is passed to the
+ * IOMMU via vcpu_info->pi_desc_addr.
+ */
pi.ga_tag = AVIC_GATAG(to_kvm_svm(kvm)->avic_vm_id,
svm->vcpu.vcpu_id);
pi.is_guest_mode = true;
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 4f69a37cf143..635774642b89 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -3860,7 +3860,7 @@ static int amd_ir_set_vcpu_affinity(struct irq_data *data, void *vcpu_info)
pi_data->prev_ga_tag = ir_data->cached_ga_tag;
if (pi_data->is_guest_mode) {
- ir_data->ga_root_ptr = (pi_data->base >> 12);
+ ir_data->ga_root_ptr = (vcpu_pi_info->pi_desc_addr >> 12);
ir_data->ga_vector = vcpu_pi_info->vector;
ir_data->ga_tag = pi_data->ga_tag;
ret = amd_iommu_activate_guest_mode(ir_data);
diff --git a/include/linux/amd-iommu.h b/include/linux/amd-iommu.h
index 062fbd4c9b77..4f433ef39188 100644
--- a/include/linux/amd-iommu.h
+++ b/include/linux/amd-iommu.h
@@ -20,7 +20,6 @@ struct amd_iommu;
struct amd_iommu_pi_data {
u32 ga_tag;
u32 prev_ga_tag;
- u64 base;
bool is_guest_mode;
struct vcpu_data *vcpu_data;
void *ir_data;
--
2.49.0.504.g3bcea36a83-goog
