Re: read physical address space

From: alan hopes
Date: Tue Nov 24 2015 - 10:48:29 EST


Thanks Yalin.

Yeah, got it.. So, it means I can't directly access physical address,
its only the responsibility of MMU to access it. Even if I have a
physical address, I need to convert it to kernel virtual address to
access it to maintain consistency with other general user-mode memory
access operation.

Thanks
Alan.

On Tue, Nov 17, 2015 at 4:28 PM, yalin wang <yalin.wang2010@xxxxxxxxx> wrote:
> you should access it like this:
> printk ( *(int*)kmap(pays_to_page(pays_addr)));
>
> pays address must be mapped into virtual address before access it .
>> On Nov 17, 2015, at 23:21, alan hopes <hopes.alan@xxxxxxxxx> wrote:
>>
>> phys_addr
>
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