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Date: Mon, 05 Jul 2010 20:19:05 +0300
From: Andriy Gapon <avg@freebsd.org>
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To: "Bjoern A. Zeeb" <bzeeb-lists@lists.zabbadoz.net>
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Cc: freebsd-hackers@freebsd.org, Konstantin Belousov <kib@freebsd.org>,
	Navdeep Parhar <np@freebsd.org>, Peter Wemm <peter@freebsd.org>
Subject: Re: elf obj load: skip zero-sized sections early
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on 05/07/2010 20:12 Bjoern A. Zeeb said the following:
> On Mon, 5 Jul 2010, Andriy Gapon wrote:
> 
>> on 02/07/2010 11:29 Bjoern A. Zeeb said the following:
>>> On Fri, 25 Jun 2010, Andriy Gapon wrote:
>>>
>>> Hey,
>>>
>>>> Proposed patch skips zero sized sections without going into trouble of
>>>> allocating section entry (progtab), doing zero-sized memory allocs and
>>>> copies.
>>>> I observe that sometimes zero-sized set_pcpu sections are produced in
>>>> module
>>>> objects, maybe when a module doesn't create any per cpu data of its
>>>> one, but
>>>> references external pcpu data.  Not sure.
>> [snip]
>>>> This work is based on np@'s investigation and original patch:
>>>> http://lists.freebsd.org/pipermail/freebsd-hackers/2009-November/030093.html
>>>>
>>>>
>>>
>>> Have you guys figured this out already?
>>
>> By 'this' - do you mean why that zero-sized section is produced at all?
>> Does it really matter why that happens?
> 
> Well, no, I was thinking of the workaround and going ahead to commit
> somehting;)

Preview? :-)


-- 
Andriy Gapon