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Date: Tue, 17 Jan 2012 17:45:23 +0100
From: Oleg Nesterov <oleg@redhat.com>
To: Will Drewry <wad@chromium.org>
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Subject: Re: [RFC,PATCH 1/2] seccomp_filters: system call filtering using
	BPF
Message-ID: <20120117164523.GA17070@redhat.com>
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On 01/16, Will Drewry wrote:
>
> On Mon, Jan 16, 2012 at 12:37 PM, Oleg Nesterov <oleg@redhat.com> wrote:
> >
> > Yes, thanks, I forgot about compat tasks again. But this is easy, just
> > we need regs_64_to_32().
>
> Yup - we could make the assumption that is_compat_task is always
> 32-bit and the pt_regs is always 64-bit, then copy_and_truncate with
> regs_64_to_32.  Seems kinda wonky though :/

much simpler/faster than what regset does to create the artificial
user_regs_struct32.

> > Doesn't matter. I think Indan has a better suggestion.
>
> I disagree, but perhaps I'm not fully understanding!

I have much more chances to be wrong ;) I leave it to you and Indan.

Oleg.