--- drivers/iommu/dmar.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) Index: linux-pm/drivers/iommu/dmar.c =================================================================== --- linux-pm.orig/drivers/iommu/dmar.c +++ linux-pm/drivers/iommu/dmar.c @@ -903,8 +903,10 @@ int __init detect_intel_iommu(void) x86_init.iommu.iommu_init = intel_iommu_init; #endif - acpi_put_table(dmar_tbl); - dmar_tbl = NULL; + if (dmar_tbl) { + acpi_put_table(dmar_tbl); + dmar_tbl = NULL; + } up_write(&dmar_global_lock); return ret ? 1 : -ENODEV;