Re: Wrong GIT author ? also bugs: serial: Add uart driver for i.MX23/28

[Sascha Hauer <s.hauer@pengutronix.de>]

Hi Alan,

On Fri, Mar 18, 2011 at 11:29:20AM +0000, Alan Cox wrote:
> >     serial: Add auart driver for i.MX23/28
> >     
> >     Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
> 
> You have a few things that need fixing, one of which is quite nasty
> 
> > + * Freescale STMP37XX/STMP378X Application UART driver
> > + *
> > + * Author: dmitry pervushin <dimka@embeddedalley.com>
> 
> So its signed off by one person and without a signature from the author ?
> Is that intentional
> 
> And it git we have
> 
> Author:     Sascha Hauer <s.hauer@pengutronix.de>
> 
> which from the header block appears to be untrue ?

The original author indeed is Dmitry with a lot of changes by myself.
Sorry, I didn't hink much while importing it to git, I should probably
have used --author while committing it.


> 
> > +static void mxs_auart_rx_chars(struct mxs_auart_port *s)
> > +{
> > +	struct tty_struct *tty = s->port.state->port.tty;
> > +	u32 stat = 0;
> 
> tty may be NULL at this point, in which case your code will try and push
> bits through a NULL pointer and crash
> 
> A user can seek to make tty NULL at the right moment by judicious use of
> vhangup, and a remote device can use carrier signals and bit timing to
> mount an attack. See tty_port_tty_get() and/or hold the port lock over
> the IRQ as other drivers do. For the uart stuff I'd hold the port lock as
> the rest of the code in the uart layer sort of assumes that
> 
> 
> > +static void mxs_auart_settermios(struct uart_port *u,
> > +				 struct ktermios *termios,
> > +				 struct ktermios *old)
> 
> Minor things here
> - You need to set the termios bits to reflect the mode you actually set.
>   So as you don't seem to support mark/space you need to clear the bit,
>   ditto h/w flow control if not supported
> 
> - You also need to report back the actual baud rate
> 
> 
> > +static irqreturn_t mxs_auart_irq_handle(int irq, void *context)
> > +{
> > +	u32 istatus, istat;
> > +	struct mxs_auart_port *s = context;
> > +	u32 stat = readl(s->port.membase + AUART_STAT);
> 
> Your IRQ handler either needs to take the port lock or have the
> underlying methods do that or their own full locking, you aren't doing
> that.
> 

I will send update patches for the comments you made soon.

BTW I wasn't aware of the linux-serial list and the according MAINTAINER
entries do not exist. Should they be added?

Sascha


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