Re: [PATCH 3/5] Blackfin SPI Driver: fix NULL pointer crash

[Andrew Morton <akpm@linux-foundation.org>]

On Thu,  5 Feb 2009 18:07:31 +0800
Bryan Wu <cooloney@kernel.org> wrote:

> From: Mike Frysinger <vapier.adi@gmail.com>
> 
> fix NULL pointer crash when cleaning up from invalid platform resources
> 
> Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
> Signed-off-by: Bryan Wu <cooloney@kernel.org>
> ---
>  drivers/spi/spi_bfin5xx.c |    3 +++
>  1 files changed, 3 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/spi/spi_bfin5xx.c b/drivers/spi/spi_bfin5xx.c
> index ce24d5e..b6098b5 100644
> --- a/drivers/spi/spi_bfin5xx.c
> +++ b/drivers/spi/spi_bfin5xx.c
> @@ -1240,6 +1240,9 @@ static void bfin_spi_cleanup(struct spi_device *spi)
>  {
>  	struct chip_data *chip = spi_get_ctldata(spi);
>  
> +	if (!chip)
> +		return;
> +
>  	if ((chip->chip_select_num > 0)
>  		&& (chip->chip_select_num <= spi->master->num_chipselect))
>  		peripheral_free(ssel[spi->master->bus_num]

This one looks like 2.6.29 material to me.

If you believe that it should be backported to earlier kernels then
please let me know.  indicating whcih kernel versions would help things
a bit, too.