This is a note to let you know that I've just added the patch titled
s390/qeth: fix thinko in IPv4 multicast address tracking
to the 4.9-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:
s390-qeth-fix-thinko-in-ipv4-multicast-address-tracking.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Thu Dec 14 11:45:58 CET 2017
From: Julian Wiedmann <jwi@xxxxxxxxxxxxxxxxxx>
Date: Fri, 1 Dec 2017 10:14:49 +0100
Subject: s390/qeth: fix thinko in IPv4 multicast address tracking
From: Julian Wiedmann <jwi@xxxxxxxxxxxxxxxxxx>
[ Upsteam commit bc3ab70584696cb798b9e1e0ac8e6ced5fd4c3b8 ]
Commit 5f78e29ceebf ("qeth: optimize IP handling in rx_mode callback")
reworked how secondary addresses are managed for qeth devices.
Instead of dropping & subsequently re-adding all addresses on every
ndo_set_rx_mode() call, qeth now keeps track of the addresses that are
currently registered with the HW.
On a ndo_set_rx_mode(), we thus only need to do (de-)registration
requests for the addresses that have actually changed.
On L3 devices, the lookup for IPv4 Multicast addresses checks the wrong
hashtable - and thus never finds a match. As a result, we first delete
*all* such addresses, and then re-add them again. So each set_rx_mode()
causes a short period where the IPv4 Multicast addresses are not
registered, and the card stops forwarding inbound traffic for them.
Fix this by setting the ->is_multicast flag on the lookup object, thus
enabling qeth_l3_ip_from_hash() to search the correct hashtable and
find a match there.
Fixes: 5f78e29ceebf ("qeth: optimize IP handling in rx_mode callback")
Signed-off-by: Julian Wiedmann <jwi@xxxxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/s390/net/qeth_l3_main.c | 1 +
1 file changed, 1 insertion(+)
--- a/drivers/s390/net/qeth_l3_main.c
+++ b/drivers/s390/net/qeth_l3_main.c
@@ -1416,6 +1416,7 @@ qeth_l3_add_mc_to_hash(struct qeth_card
tmp->u.a4.addr = im4->multiaddr;
memcpy(tmp->mac, buf, sizeof(tmp->mac));
+ tmp->is_multicast = 1;
ipm = qeth_l3_ip_from_hash(card, tmp);
if (ipm) {
Patches currently in stable-queue which might be from jwi@xxxxxxxxxxxxxxxxxx are
queue-4.9/s390-qeth-fix-thinko-in-ipv4-multicast-address-tracking.patch
queue-4.9/s390-qeth-fix-gso-throughput-regression.patch
queue-4.9/s390-qeth-fix-early-exit-from-error-path.patch
queue-4.9/s390-qeth-build-max-size-gso-skbs-on-l2-devices.patch