Message-ID: <1040314254.3e01ef8e3f7b1@209.51.155.18>
Date: Thu, 19 Dec 2002 11:10:54 -0500
From: billyrose@billyrose.net
To: root@chaos.analogic.com
Cc: linux-kernel@vger.kernel.org
Subject: Re: Intel P6 vs P7 system call performance
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Richard B. Johnson wrote:

> Because the number pushed onto the stack is a displacement, not
> an address, i.e., -4095. To have the address act as an address,
> you need to load a full-pointer, i.e. SEG:OFFSET (like the old
> 16-bit days). The offset is 32-bits and the segment is whatever
> the kernel has set up for __USER_CS (0x23). All the 'near' calls
> are calls to a signed displacement, same for jumps.

call's and jmp's use displacement, ret's are _always_ absolute.
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