AMD IOMMU: add parameter to disable device isolation

Impact: add a new AMD IOMMU kernel command line parameter

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
diff --git a/arch/x86/kernel/amd_iommu_init.c b/arch/x86/kernel/amd_iommu_init.c
index 0cdcda3..838a2e1 100644
--- a/arch/x86/kernel/amd_iommu_init.c
+++ b/arch/x86/kernel/amd_iommu_init.c
@@ -1213,6 +1213,8 @@
 	for (; *str; ++str) {
 		if (strncmp(str, "isolate", 7) == 0)
 			amd_iommu_isolate = 1;
+		if (strncmp(str, "share", 5) == 0)
+			amd_iommu_isolate = 0;
 		if (strncmp(str, "fullflush", 11) == 0)
 			amd_iommu_unmap_flush = true;
 	}