Re: A quick question on VM

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sahlot arvind wrote:
Hi All,
I just started learning Linux Virtual Memory Management Subsystem.
I see the memory is divided into three zones. Comments in file mm/mmzone.h
/*
 * ZONE_DMA       < 16 MB       ISA DMA capable memory
 * ZONE_NORMAL  16-896 MB       direct mapped by the kernel
 * ZONE_HIGHMEM  > 896 MB       only page cache and user processes
 */
Here second comment (ZONE_NORMAL) says that it is directly mapped by kernel.
Could anybody please tell me what does direct mean here?
Does this mean Physical address = Virtual Address???
It means physical address = virtual address - "a fixed offset" (which is 0xc0000000)



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