Commit b784e7eb authored by Committed by David S. Miller
L2TP:Adjust intf MTU, add underlay L3, L2 hdrs.
Existing L2TP kernel code does not derive the optimal MTU for Ethernet pseudowires and instead leaves this to a userspace L2TP daemon or operator. If an MTU is not specified, the existing kernel code chooses an MTU that does not take account of all tunnel header overheads, which can lead to unwanted IP fragmentation. When L2TP is used without a control plane (userspace daemon), we would prefer that the kernel does a better job of choosing a default pseudowire MTU, taking account of all tunnel header overheads, including IP header options, if any. This patch addresses this. Change-set here uses the new kernel function, kernel_sock_ip_overhead(), to factor the outer IP overhead on the L2TP tunnel socket (including IP Options, if any) when calculating the default MTU for an Ethernet pseudowire, along with consideration of the inner Ethernet header. Signed-off-by: R. Parameswaran <firstname.lastname@example.org> Signed-off-by: David S. Miller <email@example.com>
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