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Date:   Sat, 17 Apr 2021 16:01:36 +0200 (CEST)
From:   "Maciej W. Rozycki" <macro@orcam.me.uk>
To:     David Laight <David.Laight@ACULAB.COM>
cc:     Joe Perches <joe@perches.com>, Khalid Aziz <khalid@gonehiking.org>,
        "James E.J. Bottomley" <jejb@linux.ibm.com>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        Christoph Hellwig <hch@lst.de>,
        "linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "stable@vger.kernel.org" <stable@vger.kernel.org>
Subject: RE: [PATCH 1/5] scsi: BusLogic: Fix missing `pr_cont' use
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On Sat, 17 Apr 2021, David Laight wrote:

> > > In patch 2, vscnprintf should probably be used to make sure it's
> > > 0 terminated.
> > 
> >  Why?  C99 has this[1]:
> > 
> > "The vsnprintf function is equivalent to snprintf, with the variable
> > argument list replaced by arg, which shall have been initialized by the
> > va_start macro (and possibly subsequent va_arg calls)."
> 
> vscnprintf() is normally the function you want (not vsnprintf())
> because the return value is the number of characters actually
> put into the buffer, not the number that would have been written
> had the buffer been long enough.

 Good catch, thank you!  I'll respin the series then.  Thank you for the 
background story too!

  Maciej