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

commit b74aa02d7a30ee5e262072a7d6e8deff10b37924 upstream.

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: 3928aa3f57 ("iommu/amd: Detect and enable guest vAPIC support")
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Link: https://lore.kernel.org/r/1587562202-14183-1-git-send-email-suravee.suthikulpanit@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Suravee Suthikulpanit 2020-04-22 08:30:02 -05:00 committed by Greg Kroah-Hartman
parent a0000d228d
commit 501ecc8fc9

View File

@ -2946,7 +2946,7 @@ 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) {