Re: [PATCH 01/13] serial: linflexuart: Fix locking in set_termios

[Larisa Ileana Grigore]

On 2/16/2026 10:16 PM, Frank Li wrote:
> On Mon, Feb 16, 2026 at 04:01:53PM +0100, Larisa Grigore wrote:
> > From: Radu Pirea <radu-nicolae.pirea@xxxxxxx>
> >
> > Take the port->lock when set_termios is called, otherwise if characters
> > are sent while IP is in init mode, the IP will hang in an uncertain
> > state.
>
> According to patch, you move it before read(UARTCR). can explain why hang?
>
> Frank

Hello Frank,

Thanks for the review! This change was made to not let anyone send 
characters (for example calling `linflex_console_putchar`) while 
LINFlexD is entering INIT mode. The INIT mode is entered when setting 
LINFLEXD_LINCR1_INIT in LINCR1. UARTCR should also be protected with a 
lock since it can be modified from different other places.
I will update the commit description.

Regards,
Larisa
> > Fixes: 09864c1cdf5c ("tty: serial: Add linflexuart driver for S32V234")
> > Signed-off-by: Radu Pirea <radu-nicolae.pirea@xxxxxxx>
> > Signed-off-by: Larisa Grigore <larisa.grigore@xxxxxxxxxxx>
> > ---
> >   drivers/tty/serial/fsl_linflexuart.c | 4 ++--
> >   1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/tty/serial/fsl_linflexuart.c b/drivers/tty/serial/fsl_linflexuart.c
> > index e70a56de1fce..5a410e2d56ac 100644
> > --- a/drivers/tty/serial/fsl_linflexuart.c
> > +++ b/drivers/tty/serial/fsl_linflexuart.c
> > @@ -407,6 +407,8 @@ linflex_set_termios(struct uart_port *port, struct ktermios *termios,
> >   	unsigned long cr, old_cr, cr1;
> >   	unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
> >
> > +	uart_port_lock_irqsave(port, &flags);
> > +
> >   	cr = readl(port->membase + UARTCR);
> >   	old_cr = cr;
> >
> > @@ -475,8 +477,6 @@ linflex_set_termios(struct uart_port *port, struct ktermios *termios,
> >   		cr &= ~LINFLEXD_UARTCR_PCE;
> >   	}
> >
> > -	uart_port_lock_irqsave(port, &flags);
> > -
> >   	port->read_status_mask = 0;
> >
> >   	if (termios->c_iflag & INPCK)
> > --
> > 2.47.0