iommu/amd: Fix legacy interrupt remapping for x2APIC-enabled system

Currently, system fails to boot because the legacy interrupt remapping mode does not enable 128-bit IRTE (GA), which is required for x2APIC support. Fix by using AMD_IOMMU_GUEST_IR_LEGACY_GA mode when booting with kernel option amd_iommu_intr=legacy instead. The initialization logic will check GASup and automatically fallback to using AMD_IOMMU_GUEST_IR_LEGACY if GA mode is not supported. Fixes: 3928aa3 ("iommu/amd: Detect and enable guest vAPIC support") Signed-off-by: Suravee Suthikulpanit <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Joerg Roedel <[email protected]>
josf · May 1, 2020 · b74aa02 · b74aa02
1 parent 9dd124b
commit b74aa02
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
@@ -2936,7 +2936,7 @@ static int __init parse_amd_iommu_intr(char *str)
 {
 	for (; *str; ++str) {
 		if (strncmp(str, "legacy", 6) == 0) {
-			amd_iommu_guest_ir = AMD_IOMMU_GUEST_IR_LEGACY;
+			amd_iommu_guest_ir = AMD_IOMMU_GUEST_IR_LEGACY_GA;
 			break;
 		}
 		if (strncmp(str, "vapic", 5) == 0) {