HelenOS sources

MULTIBOOT2_TAG_ALIGN  120 kernel/genarch/src/multiboot/multiboot2.c 	    ALIGN_UP((uintptr_t) info + sizeof(*info), MULTIBOOT2_TAG_ALIGN);
MULTIBOOT2_TAG_ALIGN  139 kernel/genarch/src/multiboot/multiboot2.c 		    ALIGN_UP((uintptr_t) tag + tag->size, MULTIBOOT2_TAG_ALIGN);
HelenOS homepage, sources at GitHub