From: Sergei Trofimovich <slyfox@xxxxxxxxxx> Subject: ia64: simplify code flow around swiotlb init Before the change CONFIG_INTEL_IOMMU && !CONFIG_SWIOTLB && !CONFIG_FLATMEM could skip `set_max_mapnr(max_low_pfn);` if iommu is not present on system. Link: https://lkml.kernel.org/r/20210328202439.403601-1-slyfox@xxxxxxxxxx Signed-off-by: Sergei Trofimovich <slyfox@xxxxxxxxxx> Cc: John Paul Adrian Glaubitz <glaubitz@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/ia64/mm/init.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) --- a/arch/ia64/mm/init.c~ia64-simplify-code-flow-around-swiotlb-init +++ a/arch/ia64/mm/init.c @@ -644,13 +644,16 @@ mem_init (void) * _before_ any drivers that may need the PCI DMA interface are * initialized or bootmem has been freed. */ + do { #ifdef CONFIG_INTEL_IOMMU - detect_intel_iommu(); - if (!iommu_detected) + detect_intel_iommu(); + if (iommu_detected) + break; #endif #ifdef CONFIG_SWIOTLB swiotlb_init(1); #endif + } while (0); #ifdef CONFIG_FLATMEM BUG_ON(!mem_map); _
