diff --git a/arch/x86/kernel/pci-gart_64.c b/arch/x86/kernel/pci-gart_64.c
index a9bcdf7c8801..eb46ab3f52b2 100644
--- a/arch/x86/kernel/pci-gart_64.c
+++ b/arch/x86/kernel/pci-gart_64.c
@@ -858,7 +858,7 @@ void __init gart_parse_options(char *p)
 #endif
 	if (isdigit(*p) && get_option(&p, &arg))
 		iommu_size = arg;
-	if (!strncmp(p, "fullflush", 8))
+	if (!strncmp(p, "fullflush", 9))
 		iommu_fullflush = 1;
 	if (!strncmp(p, "nofullflush", 11))
 		iommu_fullflush = 0;