From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH x86/urgent] bpf: emulate push insns for uprobe on x86
Date: Thu, 09 Nov 2017 09:06:47 +0900 (KST)
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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.

Thank you.