x86/amd-iommu: Fix deassignment of a device from the pt_domain
Deassigning a device from the passthrough domain does not
work and breaks device assignment to kvm guests. This patch
fixes the issue.
Cc: stable@kernel.org
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 751ce73..adb0ba025 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -1511,9 +1511,11 @@
/*
* If we run in passthrough mode the device must be assigned to the
- * passthrough domain if it is detached from any other domain
+ * passthrough domain if it is detached from any other domain.
+ * Make sure we can deassign from the pt_domain itself.
*/
- if (iommu_pass_through && dev_data->domain == NULL)
+ if (iommu_pass_through &&
+ (dev_data->domain == NULL && domain != pt_domain))
__attach_device(dev, pt_domain);
}