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To: Alexey Dokuchaev <danfe@nsu.ru>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Thu, 11 Mar 2004 10:47:22 +0600."
             <20040311044722.GA93643@regency.nsu.ru> 
Date: Thu, 11 Mar 2004 07:13:07 +0100
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cc: cvs-src@freebsd.org
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Subject: Re: cvs commit: src/sys/sys mdioctl.h src/sys/dev/md md.c
	src/sbin/mdconfig mdconfig.8 mdconfig.c 
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In message <20040311044722.GA93643@regency.nsu.ru>, Alexey Dokuchaev writes:

>>   Log:
>>   Fix a long-standing deadlock issue with vnode backed md(4) devices:
>>   
>Just out of curiosity, is your fix a real fix, or just a clever
>workaround?  Meaning, there are some very in-depth issues involved that
>prevent this problem from being fixed without performance penalty?

That is a matter of taste more than anything else.  A vnode backed md(4)
device is technically a layering violation, so either the syncer or
the md(4) code itself (or both) needs to be aware of the special case.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.