diff options
| author | Andrew MacIntyre | 2024-11-08 12:44:13 +0000 |
|---|---|---|
| committer | Robert Marko | 2024-11-08 16:23:16 +0000 |
| commit | c0a50b1d59b6555c1a41303177061115c1949e2d (patch) | |
| tree | a8933bfb8fb3c5d3c12b28cae5baa3644e14029e | |
| parent | 983a753f389efb893e3b75fff1b8af28839e3f3e (diff) | |
| download | openwrt-c0a50b1d59b6555c1a41303177061115c1949e2d.tar.gz | |
vrx518_tc: allow larger MTU to support RFC4638
vrx518_tc currently sets the interface maximum MTU to the ethernet default
of 1500 bytes by default via ether_setup() called from ptm_setup().
To support 1508 byte baby jumbo frames (RFC4638) for PPPoE connections
over VDSL links as already supported by the VR9 ltq_ptm driver ([1], [2])
set the interface maximum MTU to MAX_MTU.
MAX_MTU is defined in dcdp/inc/tc_common.h to 2002 bytes and this value is
used in ptm_change_mtu() and elsewhere as the maximum MTU, however this is
short circuited by checks against the interface maximum MTU.
[1]: https://forum.openwrt.org/t/fritzbox-7530-and-rfc4638-baby-jumbo-frames/181327
[2]: https://git.openwrt.org/?p=openwrt/openwrt.git;a=commit;h=8a2a20e71e2909f84dab47e51dfda9e292a6c1ae
Signed-off-by: Andrew MacIntyre <andymac@pcug.org.au>
Link: https://github.com/openwrt/openwrt/pull/16856
Signed-off-by: Robert Marko <robimarko@gmail.com>
(cherry picked from commit ca53f2d430ce1f9ff5a560291de1e93380963417)
| -rw-r--r-- | package/kernel/lantiq/vrx518_tc/patches/206-dcdp-ptm_tc-allow-larger-mtu-to-support-rfc4638.patch | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/package/kernel/lantiq/vrx518_tc/patches/206-dcdp-ptm_tc-allow-larger-mtu-to-support-rfc4638.patch b/package/kernel/lantiq/vrx518_tc/patches/206-dcdp-ptm_tc-allow-larger-mtu-to-support-rfc4638.patch new file mode 100644 index 0000000000..35a709e9fa --- /dev/null +++ b/package/kernel/lantiq/vrx518_tc/patches/206-dcdp-ptm_tc-allow-larger-mtu-to-support-rfc4638.patch @@ -0,0 +1,34 @@ +From 3983dc1674fec43beb8ce9d9bfdd6302fef86eae Mon Sep 17 00:00:00 2001 +From: Andrew MacIntyre <andymac@pcug.org.au> +Date: Mon, 4 Nov 2024 22:41:25 +1100 +Subject: [PATCH] vrx518_tc: allow larger MTU to support RFC4638 + +vrx518_tc currently sets the interface maximum MTU to the ethernet default +of 1500 bytes by default via ether_setup() called from ptm_setup(). + +To support 1508 byte baby jumbo frames (RFC4638) for PPPoE connections +over VDSL links as already supported by the VR9 ltq_ptm driver ([1], [2]) +set the interface maximum MTU to MAX_MTU. + +MAX_MTU is defined in dcdp/inc/tc_common.h to 2002 bytes and this value is +used in ptm_change_mtu() and elsewhere as the maximum MTU, however this is +short circuited by checks against the interface maximum MTU. + +[1]: https://forum.openwrt.org/t/fritzbox-7530-and-rfc4638-baby-jumbo-frames/181327 +[2]: https://git.openwrt.org/?p=openwrt/openwrt.git;a=commit;h=8a2a20e71e2909f84dab47e51dfda9e292a6c1ae + +Signed-off-by: Andrew MacIntyre <andymac@pcug.org.au> +--- + dcdp/ptm_tc.c | 1 + + 1 file changed, 1 insertion(+) + +--- a/dcdp/ptm_tc.c 2023-12-17 16:11:22.503500398 +1100 ++++ b/dcdp/ptm_tc.c 2024-01-26 16:48:49.881623474 +1100 +@@ -657,6 +657,7 @@ static void ptm_setup(struct net_device + ether_setup(dev); + dev->watchdog_timeo = 10 * HZ; + dev->netdev_ops = &g_ptm_netdev_ops; ++ dev->max_mtu = MAX_MTU; + } + + static int ptm_dev_init(struct tc_priv *tc_priv, u32 id, |