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Date: Wed, 4 May 2005 20:42:02 +0200 (CEST)
From: Sten Spans <sten@blinkenlights.nl>
To: Maksim Yevmenkin <maksim.yevmenkin@savvis.net>
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cc: John-Mark Gurney <gurney_j@resnet.uoregon.edu>
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cc: Julian Elischer <julian@elischer.org>
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Subject: Re: if_tap unaligned access problem
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On Mon, 2 May 2005, Sten Spans wrote:

> On Mon, 2 May 2005, Maksim Yevmenkin wrote:
>
>> Hello,
>> 
>>>>>>>> i think we have few options here:
>>>>>>>> 
>>>>>>>> 1) revert back original tapwrite function that was changed in v. 1.48 
>>>>>>>> and set offset to 2 bytes in top mbuf
>>>>>>>> 
>>>>>>>> 2) change current version of tapwrite so it would m_prepend and 
>>>>>>>> m_pullup mbuf after m_uiotombuf
>>>>>>>> 
>>>>>>>> 3) change m_uiotombuf to accept one more parameter - mbuf offset at 
>>>>>>>> which data should be copied. there are not that many users of 
>>>>>>>> m_uiotombuf
>>>> 
>>>> please find and review the attached patch (untested) that implements 
>>>> option (3) above.
>> 
>> any objections to the attached (revised) patch? can i commit it?
>
>
> I've tested the code on fbsd-current alpha and it fixes
> the crash. I was kinda waiting for somebody to test it on
> sparc, but that's taking a few days longer than expected.
> I may run a test on one of my own sparcs to verify
> the results.
>
> That said, the issue seems pretty clear-cut, as is the solution.

I've gotten confirmation that the patch also fixes the crash
on RELENG_5/sparc64. Please commit.

-- 
Sten Spans

"There is a crack in everything, that's how the light gets in."
Leonard Cohen - Anthem