iommu/amd: Return an error if vCPU affinity is set for non-vCPU IRTE

Return -EINVAL instead of success if amd_ir_set_vcpu_affinity() is
invoked without use_vapic; lying to KVM about whether or not the IRTE was
configured to post IRQs is all kinds of bad.

Fixes: d98de49a53e4 ("iommu/amd: Enable vAPIC interrupt remapping mode by default")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20250404193923.1413163-6-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index be8761b..0096551 100644 (file)
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -3879,7 +3879,7 @@ static int amd_ir_set_vcpu_affinity(struct irq_data *data, void *vcpu_info)
         * we should not modify the IRTE
         */
        if (!dev_data || !dev_data->use_vapic)
-               return 0;
+               return -EINVAL;
 
        ir_data->cfg = irqd_cfg(data);
        pi_data->ir_data = ir_data;