From f483a853b0b932a1d75eb27a1dcbd732862260db Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Thu, 8 Nov 2012 16:00:16 +0000 Subject: [PATCH] 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 Signed-off-by: Will Deacon Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/processor.h | 2 ++ arch/arm64/mm/init.c | 2 +- 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h index 5d810044fed..77f696c1433 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 { diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index efbf7df05d3..4cd28931dba 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -80,7 +80,7 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max) #ifdef CONFIG_ZONE_DMA32 /* 4GB maximum for 32-bit only capable devices */ max_dma32 = min(max, MAX_DMA32_PFN); - zone_size[ZONE_DMA32] = max_dma32 - min; + zone_size[ZONE_DMA32] = max(min, max_dma32) - min; #endif zone_size[ZONE_NORMAL] = max - max_dma32; -- 2.34.1