This is the usual physical memory layout boot printout: ... [ 0.000000] Zone ranges: [ 0.000000] DMA [mem 0x00001000-0x00ffffff] [ 0.000000] DMA32 [mem 0x01000000-0xffffffff] [ 0.000000] Normal [mem 0x100000000-0xc3fffffff] [ 0.000000] Movable zone start for each node [ 0.000000] Early memory node ranges [ 0.000000] node 0: [mem 0x00001000-0x00099fff] [ 0.000000] node 0: [mem 0x00100000-0xbf78ffff] [ 0.000000] node 0: [mem 0x100000000-0x63fffffff] [ 0.000000] node 1: [mem 0x640000000-0xc3fffffff] ...
This is the log when we set "mem=2G" on the boot cmdline: ... [ 0.000000] Zone ranges: [ 0.000000] DMA [mem 0x00001000-0x00ffffff] [ 0.000000] DMA32 [mem 0x01000000-0xffffffff] // should be 0x7fffffff, right? [ 0.000000] Normal empty [ 0.000000] Movable zone start for each node [ 0.000000] Early memory node ranges [ 0.000000] node 0: [mem 0x00001000-0x00099fff] [ 0.000000] node 0: [mem 0x00100000-0x7fffffff] ... This patch fixes the printout, the following log shows the right ranges: ... [ 0.000000] Zone ranges: [ 0.000000] DMA [mem 0x00001000-0x00ffffff] [ 0.000000] DMA32 [mem 0x01000000-0x7fffffff] [ 0.000000] Normal empty [ 0.000000] Movable zone start for each node [ 0.000000] Early memory node ranges [ 0.000000] node 0: [mem 0x00001000-0x00099fff] [ 0.000000] node 0: [mem 0x00100000-0x7fffffff] ... Signed-off-by: Xishi Qiu <qiuxi...@huawei.com> Suggested-by: Andrew Morton <a...@linux-foundation.org> --- arch/x86/include/asm/dma.h | 2 +- arch/x86/mm/init.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/dma.h b/arch/x86/include/asm/dma.h index 0bdb0c5..fe884e1 100644 --- a/arch/x86/include/asm/dma.h +++ b/arch/x86/include/asm/dma.h @@ -70,7 +70,7 @@ #define MAX_DMA_CHANNELS 8 /* 16MB ISA DMA zone */ -#define MAX_DMA_PFN ((16 * 1024 * 1024) >> PAGE_SHIFT) +#define MAX_DMA_PFN ((16UL * 1024 * 1024) >> PAGE_SHIFT) /* 4GB broken PCI/AGP hardware bus master zone */ #define MAX_DMA32_PFN ((4UL * 1024 * 1024 * 1024) >> PAGE_SHIFT) diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index 66dba36..07244aa 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -674,10 +674,10 @@ void __init zone_sizes_init(void) memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); #ifdef CONFIG_ZONE_DMA - max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN; + max_zone_pfns[ZONE_DMA] = min(MAX_DMA_PFN, max_low_pfn); #endif #ifdef CONFIG_ZONE_DMA32 - max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN; + max_zone_pfns[ZONE_DMA32] = min(MAX_DMA32_PFN, max_low_pfn); #endif max_zone_pfns[ZONE_NORMAL] = max_low_pfn; #ifdef CONFIG_HIGHMEM -- 2.0.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/