From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andi Kleen <ak@linux.intel.com>
Subject: Re: [PATCH v2 3/7] x86, ptrace: Ifdef HW_BREAKPOINTS code in ptrace
Date: Mon, 10 Mar 2014 10:41:06 -0700
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> > And in fact, why do we need ptrace_get/set_debugreg(DR6) without HW_BREAKPOINTS?
> 
> Good question.  Andi?

dr6 controls single stepping which is useful even without hw/breakpoints.

Basically gdb will still work for 95+% of all use cases, everyone
not using watch points.

-Andi

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