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From: "TJ Lee" <tjmaillists@gmx.com>
To: freebsd-hackers@freebsd.org
Subject: Trying to understand kernel trap code
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Date: Thu, 6 Aug 2015 12:09:05 +0200
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Hi,
 
I just started looking at FreeBSD kernel code in more detail and want to understand the low-level entry points into the kernel on a x86-64 CPU. What I'd like to know is precisely what happens when I execute a "syscall" instruction in user-land. More specifically, what instruction in what assembly source file is RIP/CS loaded with on executing syscall? Also where in the source code do we load the MSRs with these values?
 
- tj