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Subject: Re: [RFC] [PATCH 1/7] User Space Breakpoint Assistance Layer (UBP)
From: Peter Zijlstra <peterz@infradead.org>
To: Avi Kivity <avi@redhat.com>
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Date: Mon, 18 Jan 2010 12:44:32 +0100
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On Mon, 2010-01-18 at 13:01 +0200, Avi Kivity wrote:
> 
> You've made it clear that you don't like it, but not why.
> 
> The kernel already manages the user's address space (except for 
> MAP_FIXED which is unreliable unless you've already reserved the address 
> space).  I don't see why adding a vma for debugging is so horrible. 

Well, the kernel only does what the user (and loader) tell it through
mmap(). Other than that we never (except this VDSO thing) inject vmas,
and I see no reason to start doing that now.