From mboxrd@z Thu Jan  1 00:00:00 1970
From: Yonghong Song <yhs@fb.com>
Subject: Re: [PATCH x86/urgent] bpf: emulate push insns for uprobe on x86
Date: Wed, 8 Nov 2017 16:10:19 -0800
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 <20171109.090647.824552877953564084.davem@davemloft.net>
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To: David Miller <davem@davemloft.net>
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On 11/8/17 4:06 PM, David Miller wrote:
> From: Yonghong Song <yhs@fb.com>
> Date: Wed, 8 Nov 2017 13:37:12 -0800
> 
>> Uprobe is a tracing mechanism for userspace programs.
>> Typical uprobe will incur overhead of two traps.
>> First trap is caused by replaced trap insn, and
>> the second trap is to execute the original displaced
>> insn in user space.
>   ...
> 
> I don't understand how this is bpf related, and if it is you don't
> explain it well in the commit message.

Right. This is not related to bpf. Will remove the "bpf" from the 
subject line in the next revision.

> 
> Thank you.
>