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From:   Song Liu <songliubraving@fb.com>
To:     Luis Chamberlain <mcgrof@kernel.org>
CC:     Song Liu <song@kernel.org>, bpf <bpf@vger.kernel.org>,
        lkml <linux-kernel@vger.kernel.org>,
        Linux-MM <linux-mm@kvack.org>,
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        "dave.hansen@linux.intel.com" <dave.hansen@linux.intel.com>,
        "rick.p.edgecombe@intel.com" <rick.p.edgecombe@intel.com>
Subject: Re: [PATCH v6 bpf-next 0/5] bpf_prog_pack followup
Thread-Topic: [PATCH v6 bpf-next 0/5] bpf_prog_pack followup
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Date:   Fri, 8 Jul 2022 01:36:25 +0000
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> On Jul 7, 2022, at 5:53 PM, Luis Chamberlain <mcgrof@kernel.org> wrote:
> 
> On Thu, Jul 07, 2022 at 11:52:58PM +0000, Song Liu wrote:
>>> On Jul 7, 2022, at 3:59 PM, Luis Chamberlain <mcgrof@kernel.org> wrote:
>>> 
>>> On Thu, Jul 07, 2022 at 03:35:41PM -0700, Song Liu wrote:
>>>> This set is the second half of v4 [1].
>>>> 
>>>> Changes v5 => v6:
>>>> 1. Rebase and extend CC list.
>>> 
>>> Why post a new iteration so soon without completing the discussion we
>>> had? It seems like we were at least going somewhere. If it's just
>>> to include mm as I requested, sure, that's fine, but this does not
>>> provide context as to what we last were talking about.
>> 
>> Sorry for sending v6 too soon. The primary reason was to extend the CC
>> list and add it back to patchwork (v5 somehow got archived). 
>> 
>> Also, I think vmalloc_exec_ work would be a separate project, while this 
>> set is the followup work of bpf_prog_pack. Does this make sense? 
>> 
>> Btw, vmalloc_exec_ work could be a good topic for LPC. It will be much
>> more efficient to discuss this in person. 
> 
> What we need is input from mm / arch folks. What is not done here is
> what that stuff we're talking about is and so mm folks can't guess. My
> preference is to address that.
> 
> I don't think in person discussion is needed if the only folks
> discussing this topic so far is just you and me.

How about we start a thread with mm / arch folks for the vmalloc_exec_*
topic? I will summarize previous discussions and include pointers to 
these discussions. If necessary, we can continue the discussion at LPC.

OTOH, I guess the outcome of that discussion should not change this set? 
If we have concern about module_alloc_huge(), maybe we can have bpf code 
call vmalloc directly (until we have vmalloc_exec_)? 

What do you think about this plan?

Thanks,
Song