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Date: Thu, 4 Jun 2009 13:04:23 +0100 (WEST)
From: "Maciej W. Rozycki" <macro@linux-mips.org>
To: Roel Kluin <roel.kluin@gmail.com>
cc: davem@davemloft.net, lkml <linux-kernel@vger.kernel.org>,
       Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH] serial: off by one
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On Thu, 4 Jun 2009, Roel Kluin wrote:

> In zs_console_putchar() occurs:
> 
> 	if (zs_transmit_drain(zport, irq))
> 		write_zsdata(zport, ch);
> 
> However if in zs_transmit_drain() no empty Tx Buffer occurs, limit reaches
> -1 => true, and the write still occurs.
> 
> This patch changes postfix to prefix decrements in this and similar
> functions to prevent similar mistakes in the future. This decreases the
> iterations with one but the chosen loop count was arbitrary anyway.
> 
> In sunhv limit reaches -1, not 0, so the test is off by one.
> 
> Signed-off-by: Roel Kluin <roel.kluin@gmail.com>

Acked-by: Maciej W. Rozycki <macro@linux-mips.org>

  Maciej