From mboxrd@z Thu Jan  1 00:00:00 1970
From: Oleg Nesterov <oleg@redhat.com>
Subject: Re: [PATCH][v3] uprobes/x86: emulate push insns for uprobe on x86
Date: Wed, 15 Nov 2017 18:07:34 +0100
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On 11/15, Oleg Nesterov wrote:
>
> So please, check if uprobe_init_insn() fails or not in this case. After that
> we will know whether your patch needs the additional is_64bit_mm() check in
> push_setup_xol_ops() or not.

OK, I did the check for you.

uprobe_init_insn() doesn't fail but insn_init(x86_64 => 0) parse it as
single-byte insn with OPCODE1 == 0x41, so push_setup_xol_ops() doesn't
need to worry about compat tasks.

In short, your "V2" should be fine except you can factor out
auprobe->push.ilen initialization (as you did in V3). Please send V4.

Oleg.