arm64: mm: fix booting on systems with no memory below 4GB

Booting on a system with all of its memory above the 4GB boundary breaks
for two reasons:

	(1) We still try to create a non-empty DMA32 zone
	(2) no-bootmem limits allocations to 0xffffffff

This patch fixes these issues for ARM64.

Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h
index 5d810044feda..77f696c14339 100644
--- a/arch/arm64/include/asm/processor.h
+++ b/arch/arm64/include/asm/processor.h
@@ -43,6 +43,8 @@
 #else
 #define STACK_TOP               STACK_TOP_MAX
 #endif /* CONFIG_COMPAT */
+
+#define ARCH_LOW_ADDRESS_LIMIT  PHYS_MASK
 #endif /* __KERNEL__ */
 
 struct debug_info {