From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefan Mavrodiev Date: Thu, 20 Dec 2018 12:48:30 +0200 Subject: [U-Boot] [PATCH 1/1] arm: sunxi: Add NULL pointer check In-Reply-To: References: <20181205122757.14523-1-stefan@olimex.com> Message-ID: <18e25666-911a-8dc6-f8f5-223f1761eafa@olimex.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On 12/20/18 12:45 PM, Jagan Teki wrote: > On Thu, Dec 20, 2018 at 3:59 PM Stefan Mavrodiev wrote: >> >> On 12/20/18 12:14 PM, Jagan Teki wrote: >>> On Fri, Dec 14, 2018 at 3:48 PM Jagan Teki wrote: >>>> On Wed, Dec 5, 2018 at 5:58 PM Stefan Mavrodiev wrote: >>>>> Current driver doesn't check if the destination pointer is NULL. >>>>> This cause the data from the FIFO to be stored inside the internal >>>>> SDRAM ( address 0 ). >>>>> >>>>> The patch add simple check if the destination pointer is NULL. >>>>> >>>>> Signed-off-by: Stefan Mavrodiev >>>>> --- >>>>> drivers/spi/sun4i_spi.c | 3 ++- >>>>> 1 file changed, 2 insertions(+), 1 deletion(-) >>>>> >>>>> diff --git a/drivers/spi/sun4i_spi.c b/drivers/spi/sun4i_spi.c >>>>> index b86b5a00ad..38cc743c61 100644 >>>>> --- a/drivers/spi/sun4i_spi.c >>>>> +++ b/drivers/spi/sun4i_spi.c >>>>> @@ -129,7 +129,8 @@ static inline void sun4i_spi_drain_fifo(struct sun4i_spi_priv *priv, int len) >>>>> >>>>> while (len--) { >>>>> byte = readb(&priv->regs->rxdata); >>>>> - *priv->rx_buf++ = byte; >>>>> + if (priv->rx_buf) >>>>> + *priv->rx_buf++ = byte; >>>> Acked-by: Jagan Teki >>>> >>>> But, have you tested how much data in the fifo before drained? It's >>>> better we can get the available data before reading via fifo_sta >> I don't understand what's the point of doing this? > Didn't get? don't you understand what I'm saying or it not require > from point of you? Maybe I don't understand correctly what you're saying.