Patch "can: cc770: Fix stalls on rt-linux, remove redundant IRQ ack" has been added to the 4.4-stable tree

Patch "can: cc770: Fix stalls on rt-linux, remove redundant IRQ ack" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    can: cc770: Fix stalls on rt-linux, remove redundant IRQ ack

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     can-cc770-fix-stalls-on-rt-linux-remove-redundant-irq-ack.patch
and it can be found in the queue-4.4 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 f4353daf4905c0099fd25fa742e2ffd4a4bab26a Mon Sep 17 00:00:00 2001
From: Andri Yngvason <andri.yngvason@marel.com>
Date: Wed, 14 Mar 2018 11:52:56 +0000
Subject: can: cc770: Fix stalls on rt-linux, remove redundant IRQ ack

From: Andri Yngvason <andri.yngvason@marel.com>

commit f4353daf4905c0099fd25fa742e2ffd4a4bab26a upstream.

This has been reported to cause stalls on rt-linux.

Suggested-by: Richard Weinberger <richard@nod.at>
Tested-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Andri Yngvason <andri.yngvason@marel.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/net/can/cc770/cc770.c |   15 ---------------
 1 file changed, 15 deletions(-)

--- a/drivers/net/can/cc770/cc770.c
+++ b/drivers/net/can/cc770/cc770.c
@@ -447,15 +447,6 @@ static netdev_tx_t cc770_start_xmit(stru
 
 	stats->tx_bytes += dlc;
 
-
-	/*
-	 * HM: We had some cases of repeated IRQs so make sure the
-	 * INT is acknowledged I know it's already further up, but
-	 * doing again fixed the issue
-	 */
-	cc770_write_reg(priv, msgobj[mo].ctrl0,
-			MSGVAL_UNC | TXIE_UNC | RXIE_UNC | INTPND_RES);
-
 	return NETDEV_TX_OK;
 }
 
@@ -684,12 +675,6 @@ static void cc770_tx_interrupt(struct ne
 	/* Nothing more to send, switch off interrupts */
 	cc770_write_reg(priv, msgobj[mo].ctrl0,
 			MSGVAL_RES | TXIE_RES | RXIE_RES | INTPND_RES);
-	/*
-	 * We had some cases of repeated IRQ so make sure the
-	 * INT is acknowledged
-	 */
-	cc770_write_reg(priv, msgobj[mo].ctrl0,
-			MSGVAL_UNC | TXIE_UNC | RXIE_UNC | INTPND_RES);
 
 	stats->tx_packets++;
 	can_get_echo_skb(dev, 0);


Patches currently in stable-queue which might be from andri.yngvason@marel.com are

queue-4.4/can-cc770-fix-use-after-free-in-cc770_tx_interrupt.patch
queue-4.4/can-cc770-fix-queue-stall-dropped-rtr-reply.patch
queue-4.4/can-cc770-fix-stalls-on-rt-linux-remove-redundant-irq-ack.patch