[PATCH v3 56/62] iommu/amd: WARN if KVM calls GA IRTE helpers without virtual APIC support
From: Sean Christopherson <seanjc@google.com>
Date: 2025-06-11 22:48:33
Also in:
kvm, kvmarm, linux-iommu, lkml
Subsystem:
amd iommu (amd-vi), iommu subsystem, the rest · Maintainers:
Joerg Roedel, Will Deacon, Linus Torvalds
WARN if KVM attempts to update IRTE entries when virtual APIC isn't fully supported, as KVM should guard all such calls on IRQ posting being enabled. Signed-off-by: Sean Christopherson <seanjc@google.com> --- drivers/iommu/amd/iommu.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-)
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index becef69a306d..926dcdfe08c8 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c@@ -3836,8 +3836,10 @@ int amd_iommu_update_ga(int cpu, void *data) struct amd_ir_data *ir_data = (struct amd_ir_data *)data; struct irte_ga *entry = (struct irte_ga *) ir_data->entry; - if (!AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir) || - !entry || !entry->lo.fields_vapic.guest_mode) + if (WARN_ON_ONCE(!AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir))) + return -EINVAL; + + if (!entry || !entry->lo.fields_vapic.guest_mode) return 0; if (!ir_data->iommu)
@@ -3856,7 +3858,10 @@ int amd_iommu_activate_guest_mode(void *data, int cpu) struct irte_ga *entry = (struct irte_ga *) ir_data->entry; u64 valid; - if (!AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir) || !entry) + if (WARN_ON_ONCE(!AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir))) + return -EINVAL; + + if (!entry) return 0; valid = entry->lo.fields_vapic.valid;
@@ -3885,8 +3890,10 @@ int amd_iommu_deactivate_guest_mode(void *data) struct irq_cfg *cfg = ir_data->cfg; u64 valid; - if (!AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir) || - !entry || !entry->lo.fields_vapic.guest_mode) + if (WARN_ON_ONCE(!AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir))) + return -EINVAL; + + if (!entry || !entry->lo.fields_vapic.guest_mode) return 0; valid = entry->lo.fields_remap.valid;
--
2.50.0.rc1.591.g9c95f17f64-goog