This is a note to let you know that I've just added the patch titled
can: sun4i: handle overrun in RX FIFO
to the 4.13-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: can-sun4i-handle-overrun-in-rx-fifo.patch and it can be found in the queue-4.13 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From 4dcf924c2eda0c47a5c53b7703e3dc65ddaa8920 Mon Sep 17 00:00:00 2001
From: Gerhard Bertelsmann info@gerhard-bertelsmann.de Date: Mon, 6 Nov 2017 18:16:56 +0100 Subject: can: sun4i: handle overrun in RX FIFO
From: Gerhard Bertelsmann info@gerhard-bertelsmann.de
commit 4dcf924c2eda0c47a5c53b7703e3dc65ddaa8920 upstream.
SUN4Is CAN IP has a 64 byte deep FIFO buffer. If the buffer is not drained fast enough (overrun) it's getting mangled. Already received frames are dropped - the data can't be restored.
Signed-off-by: Gerhard Bertelsmann info@gerhard-bertelsmann.de Signed-off-by: Marc Kleine-Budde mkl@pengutronix.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/net/can/sun4i_can.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-)
--- a/drivers/net/can/sun4i_can.c +++ b/drivers/net/can/sun4i_can.c @@ -539,6 +539,13 @@ static int sun4i_can_err(struct net_devi } stats->rx_over_errors++; stats->rx_errors++; + + /* reset the CAN IP by entering reset mode + * ignoring timeout error + */ + set_reset_mode(dev); + set_normal_mode(dev); + /* clear bit */ sun4i_can_write_cmdreg(priv, SUN4I_CMD_CLEAR_OR_FLAG); } @@ -653,8 +660,9 @@ static irqreturn_t sun4i_can_interrupt(i netif_wake_queue(dev); can_led_event(dev, CAN_LED_EVENT_TX); } - if (isrc & SUN4I_INT_RBUF_VLD) { - /* receive interrupt */ + if ((isrc & SUN4I_INT_RBUF_VLD) && + !(isrc & SUN4I_INT_DATA_OR)) { + /* receive interrupt - don't read if overrun occurred */ while (status & SUN4I_STA_RBUF_RDY) { /* RX buffer is not empty */ sun4i_can_rx(dev);
Patches currently in stable-queue which might be from info@gerhard-bertelsmann.de are
queue-4.13/can-sun4i-handle-overrun-in-rx-fifo.patch