Re: [PATCH] serial: off by one

[Maciej W. Rozycki]

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@xxxxxxxxx>

Acked-by: Maciej W. Rozycki <macro@xxxxxxxxxxxxxx>

  Maciej
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