diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h index 364635b8370a689edf8a9c2fd02d1f155f58bdfb..0204c2006c92790ed4aec4d31e126b47e0a9f49d 100644 --- a/arch/arm64/include/asm/memory.h +++ b/arch/arm64/include/asm/memory.h @@ -26,8 +26,15 @@ /* * VMEMMAP_SIZE - allows the whole linear region to be covered by * a struct page array + * + * If we are configured with a 52-bit kernel VA then our VMEMMAP_SIZE + * neads to cover the memory region from the beginning of the 52-bit + * PAGE_OFFSET all the way to VA_START for 48-bit. This allows us to + * keep a constant PAGE_OFFSET and "fallback" to using the higher end + * of the VMEMMAP where 52-bit support is not available in hardware. */ -#define VMEMMAP_SIZE (UL(1) << (VA_BITS - PAGE_SHIFT - 1 + STRUCT_PAGE_MAX_SHIFT)) +#define VMEMMAP_SIZE ((_VA_START(VA_BITS_MIN) - PAGE_OFFSET) \ + >> (PAGE_SHIFT - STRUCT_PAGE_MAX_SHIFT)) /* * PAGE_OFFSET - the virtual address of the start of the linear map (top