summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorSean Christopherson <seanjc@google.com>2025-06-11 15:45:24 -0700
committerSean Christopherson <seanjc@google.com>2025-06-23 09:50:24 -0700
commitc4cdbaf9d81c8387da8b9b91567d4b0eb1b8a549 (patch)
treecd43591a9d70e62a7eed4e61c23fa4238048eb1c
parent52d826c9e54cc6b4f0107720dd1f254944f6e727 (diff)
iommu/amd: KVM: SVM: Use pi_desc_addr to derive ga_root_ptr
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@redhat.com> Reviewed-by: Joao Martins <joao.m.martins@oracle.com> Reviewed-by: Vasant Hegde <vasant.hegde@amd.com> Tested-by: Sairaj Kodilkar <sarunkod@amd.com> Link: https://lore.kernel.org/r/20250611224604.313496-23-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
-rw-r--r--arch/x86/kvm/svm/avic.c7
-rw-r--r--drivers/iommu/amd/iommu.c2
-rw-r--r--include/linux/amd-iommu.h2
3 files changed, 6 insertions, 5 deletions
diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c
index 375a29022000..d95742faae11 100644
--- a/arch/x86/kvm/svm/avic.c
+++ b/arch/x86/kvm/svm/avic.c
@@ -894,8 +894,11 @@ 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 ed96050d4933..bdfb57af7111 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -3888,7 +3888,7 @@ static int amd_ir_set_vcpu_affinity(struct irq_data *data, void *vcpu_info)
pi_data->ir_data = ir_data;
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 1f9b13d803c5..deeefc92a5cf 100644
--- a/include/linux/amd-iommu.h
+++ b/include/linux/amd-iommu.h
@@ -19,8 +19,6 @@ struct amd_iommu;
*/
struct amd_iommu_pi_data {
u32 ga_tag;
- u64 base;
-
bool is_guest_mode;
struct vcpu_data *vcpu_data;
void *ir_data;