From 658e2ebce5213897665f8488f951364a5eb5d96b Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Fri, 14 Aug 2015 18:01:03 +0200 Subject: [PATCH] serial: 8250_omap: check how many bytes were injected The function tty_insert_flip_string() returns an int and as such it might fail. So the result is that I kindly asked to insert 48 bytes and the function only insterted 32. I have no idea what to do with the remaining 16 so I think dropping them is the only option. I also increase the buf_overrun counter so userpace has a clue that we lost bytes. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Tested-by: Sekhar Nori <nsekhar@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- drivers/tty/serial/8250/8250_omap.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c index 826c5c4a2103b..6efe4dd6e77ad 100644 --- a/drivers/tty/serial/8250/8250_omap.c +++ b/drivers/tty/serial/8250/8250_omap.c @@ -726,6 +726,7 @@ static void __dma_rx_do_complete(struct uart_8250_port *p, bool error) struct dma_tx_state state; int count; unsigned long flags; + int ret; dma_sync_single_for_cpu(dma->rxchan->device->dev, dma->rx_addr, dma->rx_size, DMA_FROM_DEVICE); @@ -741,8 +742,10 @@ static void __dma_rx_do_complete(struct uart_8250_port *p, bool error) count = dma->rx_size - state.residue; - tty_insert_flip_string(tty_port, dma->rx_buf, count); - p->port.icount.rx += count; + ret = tty_insert_flip_string(tty_port, dma->rx_buf, count); + + p->port.icount.rx += ret; + p->port.icount.buf_overrun += count - ret; unlock: spin_unlock_irqrestore(&priv->rx_dma_lock, flags); -- 2.30.2