@@ -64,13 +64,13 @@
We cannot track such dead loops during route installation,
it is infeasible task. The most general solutions would be
to keep skb->encapsulation counter (sort of local ttl),
- and silently drop packet when it expires. It is the best
+ and silently drop packet when it expires. It is a good
solution, but it supposes maintaing new variable in ALL
skb, even if no tunneling is used.
- Current solution: HARD_TX_LOCK lock breaks dead loops.
-
-
+ Current solution: xmit_recursion breaks dead loops. This is a percpu
+ counter, since when we enter the first ndo_xmit(), cpu migration is
+ forbidden. We force an exit if this counter reaches RECURSION_LIMIT
2. Networking dead loops would not kill routers, but would really
kill network. IP hop limit plays role of "t->recursion" in this case,
HARD_TX_LOCK no longer protects tunnels from dead loops, but xmit_recursion percpu counter. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> --- net/ipv4/ip_gre.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html