On Thu, Nov 03, 2016 at 06:26:57PM +0200, Andy Shevchenko wrote: > Static analyzer can not see balanced locking if the lock is acquired and > released conditionally. Add __acquire() and __release() markings in the right > locations so that sparse isn't tripped up on the conditional locking. > > drivers/tty/serial/serial_core.c:131:17: warning: context imbalance in 'uart_stop' - unexpected unlock > include/linux/spinlock.h:362:9: warning: context imbalance in 'uart_start' - unexpected unlock > include/linux/spinlock.h:362:9: warning: context imbalance in 'uart_put_char' - unexpected unlock > include/linux/spinlock.h:362:9: warning: context imbalance in 'uart_write' - unexpected unlock > include/linux/spinlock.h:362:9: warning: context imbalance in 'uart_write_room' - unexpected unlock > include/linux/spinlock.h:362:9: warning: context imbalance in 'uart_chars_in_buffer' - unexpected unlock > include/linux/spinlock.h:362:9: warning: context imbalance in 'uart_flush_buffer' - unexpected unlock > > Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> > --- > drivers/tty/serial/serial_core.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c > index f2303f3..ff90c8e 100644 > --- a/drivers/tty/serial/serial_core.c > +++ b/drivers/tty/serial/serial_core.c > @@ -82,6 +82,8 @@ static inline void uart_port_deref(struct uart_port *uport) > struct uart_port *__uport = uart_port_ref(state); \ > if (__uport) \ > spin_lock_irqsave(&__uport->lock, flags); \ > + else \ > + __acquire(&__uport->lock); \ That doesn't make much logical sense. Yes, I know __acquire is just a crazy macro, but really, look at what you just wrote and tell me that someone who doesn't know what __acquire does, would instantly think this is a null pointer dereference. Please fix. > __uport; \ > }) > > @@ -90,6 +92,8 @@ static inline void uart_port_deref(struct uart_port *uport) > struct uart_port *__uport = uport; \ > if (__uport) \ > spin_unlock_irqrestore(&__uport->lock, flags); \ > + else \ > + __release(&__uport->lock); \ Same here. greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
