From f661131766e45bc0b3c8b85b19676a470dc75abf Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Fri, 6 Jul 2018 11:05:42 +0200 Subject: [PATCH] serial: sh-sci: Stop TX DMA workqueue during port shutdown The transmit DMA workqueue is never stopped, hence the work function may be called after the port has been shut down. Fix this race condition by cancelling queued work, if any, before DMA release. Don't initialize the work if DMA initialization failed, as it won't be used anyway. Signed-off-by: Geert Uytterhoeven Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/sh-sci.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c index c5c891c8714e..f3432cca3fdc 100644 --- a/drivers/tty/serial/sh-sci.c +++ b/drivers/tty/serial/sh-sci.c @@ -1293,6 +1293,7 @@ static void sci_tx_dma_release(struct sci_port *s) { struct dma_chan *chan = s->chan_tx_saved; + cancel_work_sync(&s->work_tx); s->chan_tx_saved = s->chan_tx = NULL; s->cookie_tx = -EINVAL; dmaengine_terminate_all(chan); @@ -1548,10 +1549,9 @@ static void sci_request_dma(struct uart_port *port) __func__, UART_XMIT_SIZE, port->state->xmit.buf, &s->tx_dma_addr); + INIT_WORK(&s->work_tx, work_fn_tx); s->chan_tx_saved = s->chan_tx = chan; } - - INIT_WORK(&s->work_tx, work_fn_tx); } chan = sci_request_dma_chan(port, DMA_DEV_TO_MEM); -- 2.17.1