This is a note to let you know that I've just added the patch titled batman-adv: Trigger events for auto adjusted MTU to the 5.10-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: batman-adv-trigger-events-for-auto-adjusted-mtu.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From c6a953cce8d0438391e6da48c8d0793d3fbfcfa6 Mon Sep 17 00:00:00 2001 From: Sven Eckelmann <sven@xxxxxxxxxxxxx> Date: Wed, 19 Jul 2023 09:29:29 +0200 Subject: batman-adv: Trigger events for auto adjusted MTU From: Sven Eckelmann <sven@xxxxxxxxxxxxx> commit c6a953cce8d0438391e6da48c8d0793d3fbfcfa6 upstream. If an interface changes the MTU, it is expected that an NETDEV_PRECHANGEMTU and NETDEV_CHANGEMTU notification events is triggered. This worked fine for .ndo_change_mtu based changes because core networking code took care of it. But for auto-adjustments after hard-interfaces changes, these events were simply missing. Due to this problem, non-batman-adv components weren't aware of MTU changes and thus couldn't perform their own tasks correctly. Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Sven Eckelmann <sven@xxxxxxxxxxxxx> Signed-off-by: Simon Wunderlich <sw@xxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/batman-adv/hard-interface.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/batman-adv/hard-interface.c +++ b/net/batman-adv/hard-interface.c @@ -632,7 +632,7 @@ out: */ void batadv_update_min_mtu(struct net_device *soft_iface) { - soft_iface->mtu = batadv_hardif_min_mtu(soft_iface); + dev_set_mtu(soft_iface, batadv_hardif_min_mtu(soft_iface)); /* Check if the local translate table should be cleaned up to match a * new (and smaller) MTU. Patches currently in stable-queue which might be from sven@xxxxxxxxxxxxx are queue-5.10/batman-adv-fix-tt-global-entry-leak-when-client-roamed-back.patch queue-5.10/batman-adv-don-t-increase-mtu-when-set-by-user.patch queue-5.10/batman-adv-do-not-get-eth-header-before-batadv_check_management_packet.patch queue-5.10/batman-adv-trigger-events-for-auto-adjusted-mtu.patch queue-5.10/batman-adv-hold-rtnl-lock-during-mtu-update-via-netlink.patch queue-5.10/batman-adv-fix-batadv_v_ogm_aggr_send-memory-leak.patch