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Date: Tue, 11 Mar 2014 09:37:10 -0400
From: Vivek Goyal <vgoyal@redhat.com>
Subject: Re: [PATCH] vmcore-dmesg stack smashing happend in extreme case
Message-ID: <20140311133710.GA14785@redhat.com>
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To: Zhi Zou <zzou@redhat.com>
Cc: kexec@lists.infradead.org

On Mon, Mar 10, 2014 at 09:42:18PM -0400, Zhi Zou wrote:

[..]
> > 
> > And we don't have to do this twice. Just do it once inside innermost
> > for loop.
> 
> At the beginning, I think it is unnecessary to do this twice too. But
> if the text_len ==0  then the for loop won't be executed and check won't
> be executed either. May be this situation never come up, considering it's
> cost, I can accept it because most of time we just do the check instead of
> write. If it is sure that text_len == 0 never come up, then we should remove
> it.

When do we get text_len=0? If text_len=0, then we are just printing time
stamp? Does it really happen?

I think do a quick test and if we are not encountering such cases, don't
worry about it right now. Making logic too complicated does not help.

Thanks
Vivek

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