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Re: Why need the Global Descriptor Table in the kernel?

To: lk <linux_kernel@xxxxxxxxx>
Subject: Re: Why need the Global Descriptor Table in the kernel?
From: Xiangfei Jia <xjianz@xxxxxxxxx>
Date: Wed, 8 Jun 2005 20:32:29 +1200
Cc: kernelnewbies@xxxxxxxxxxxx
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Reply-to: Xiangfei Jia <xjianz@xxxxxxxxx>
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THANKS for your reply again!!!

Some of the segments used by Linux are, defined in GDT: kernel code segment, kernel data segment, user code segment, and user data segment. All these segment have the 'base=0x00000000' and 'Limit=0xfffff', which means they all share the same full range of memory. This means they all share the same linear address space. What I can't understand is that why don't the kernel just use linear addresses, without worrying logical address. Beause to me, the logical address makes no use in this case.

Regards!

Fei

Follow-Ups:
- Re: Why need the Global Descriptor Table in the kernel?
  - From: Martin Jambor

References:
- Why need the Global Descriptor Table in the kernel?
  - From: Xiangfei Jia
- Re: Why need the Global Descriptor Table in the kernel?
  - From: lk

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