Re: read physical address space

From	alan hopes <hopes.alan@gmail.com>
Newsgroups	linux.kernel
Subject	Re: read physical address space
Date	2015-11-24 16:50 +0100
Message-ID	<qyo0W-1By-7@gated-at.bofh.it> (permalink)
References	<qvQmJ-6NX-3@gated-at.bofh.it> <qvRLR-7AN-21@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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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@gmail.com> 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@gmail.com> wrote:
>>
>> phys_addr
>
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read physical address space alan hopes <hopes.alan@gmail.com> - 2015-11-17 16:30 +0100
  Re: read physical address space yalin wang <yalin.wang2010@gmail.com> - 2015-11-17 18:00 +0100
    Re: read physical address space alan hopes <hopes.alan@gmail.com> - 2015-11-24 16:50 +0100

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