amd-iommu: don't free dma adresses below 512MB with CONFIG_IOMMU_STRESS
This will test the automatic aperture enlargement code. This is
important because only very few devices will ever trigger this code
path. So force it under CONFIG_IOMMU_STRESS.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index 33434c4..04ff5ec 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -824,6 +824,11 @@
BUG_ON(i >= APERTURE_MAX_RANGES || range == NULL);
+#ifdef CONFIG_IOMMU_STRESS
+ if (i < 4)
+ return;
+#endif
+
if (address >= dom->next_address)
dom->need_flush = true;