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Date: Fri, 2 Dec 2005 16:45:51 +0100
From: Csaba Henk <csaba-ml@creo.hu>
To: Robert Watson <rwatson@freebsd.org>
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Cc: freebsd-current@freebsd.org, Kris Kennaway <kris@obsecurity.org>
Subject: Re: double close strikes panic if md attaching a corrupt file
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On Sat, Nov 26, 2005 at 12:43:36PM +0000, Robert Watson wrote:
> 
> On Sat, 26 Nov 2005, Csaba Henk wrote:
> 
> >On Fri, Nov 25, 2005 at 09:56:20PM -0500, Kris Kennaway wrote:
> >>You probably should do so ;-) This isn't the easiest thing for someone
> >>to test without such corrupted media.
 [...]
> Well, a very easy way to test would be to add a local modification to UFS 
> to create a file flag that causes VOP_READ to return EIO :-).  That way 
> you can easily mark files to return EIO.

OK, I've been there, done that.

Tried both with UFS + an SF_IOERROR flag and with a hacked reiserfs, where
reading from regular files always fails.

Original md code does choke on EIO returned.

After I applied my first patch (md-doubleclose-1.diff), all worked fine, both
in the case when reading returns error and when reading works normally.

Csaba