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From:   Mike Marshall <hubcap@omnibond.com>
Date:   Tue, 25 Jun 2019 14:55:11 -0400
Message-ID: <CAOg9mSQmV=BDMpTNLJvb4QBr=f96qg4Hr9qu=bB6xZubB+1LZQ@mail.gmail.com>
Subject: Re: [PATCH] orangefs: remove redundant assignment to variable buffer_index
To:     Dan Carpenter <dan.carpenter@oracle.com>,
        Mike Marshall <hubcap@omnibond.com>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>
Cc:     Colin King <colin.king@canonical.com>,
        Martin Brandenburg <martin@omnibond.com>,
        devel@lists.orangefs.org, kernel-janitors@vger.kernel.org,
        LKML <linux-kernel@vger.kernel.org>
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>> The only explanation I can think of is that you guys are discussing
>> different code. :P

My response contained several conflations :-) ...

The code in file.c that Colin has flagged does indeed have buffer_index
being initialized needlessly, and the assignment noted by Dan is also
needless. There's even a second needless assignment done in another
place in the same function. While the code around them has changed over
time, these now needless manipulations of buffer_index are not new. I'll
get rid of them.

>> You often send these patches before they hit linux-next so I had skipped
>> reviewing this one when you sent it.

I know Linus is likely to refuse pull requests for stuff that
has not been through linux-next, so I make sure stuff has been
there at least a few days before asking for it to be pulled.
"A few days" is long enough for robots to see it, perhaps not
long enough for humans. I especially appreciate the human review. One of
the good things about Orangefs is that it is easy to install and configure,
especially for testing. Documentation/filesystems/orangefs.txt has
instructions for dnf installing orangefs on Fedora, and also how to download
a source tarball and install from that.

-Mike

On Tue, May 21, 2019 at 11:04 AM Dan Carpenter <dan.carpenter@oracle.com> wrote:
>
> On Thu, May 16, 2019 at 12:06:31PM -0400, Mike Marshall wrote:
> > Hi Colin...
> >
> > Thanks for the patch. Before I initialized buffer_index, Dan Williams sent
> > in a warning that a particular error path could try to use ibuffer_index
> > uninitialized. I could induce the problem he described with one
> > of the xfstests resulting in a crashed kernel. I will try to refactor
> > the code to fix the problem some other way than initializing
> > buffer_index in the declaration.
> >
>
> The only explanation I can think of is that you guys are discussing
> different code.  :P
>
> regards,
> dan carpenter
>