Re: [PATCH v2 0/4] Reworks and improvements to TCP activity timers

On Wed, Feb 25, 2026 at 07:15:45AM +0100, Stefano Brivio wrote:

On Fri, 6 Feb 2026 17:17:35 +1100 David Gibson wrote:

...

Here's a bunch of patches aimed at fixing bug 179, and reworking the currently broken inactivity timer along the way.

I believe patches 1..2/4 are ready to go - I've tested them, and I'm happy with how they're behaving. Patches 3..4/4 I think are correct, but I've been getting bogged down in details trying to test them in the specific FIN_WAIT_2 situation that occurs in bug 179.

I just tested things manually by cycling guest interfaces and checking that keepalives come and eventually cause connection resets, as well as that the activity timeout (shortened via define) triggers after the expected time.

Nice.

It's not great but I couldn't figure out a way to simulate the issue with a single namespace test (without any connecting interface that can be brought down), and simulating this with multiple namespaces connected via veth looks doable, but not easy to integrate with the existing tests.

Right. I think it can be tested without bouncing interfaces at all - however it needs quite specific behaviour from both the client and the server. I couldn't figure out a way to convince socat to do what I wanted, so it would probably need custom endpoint programs.

Meanwhile the reporter of https://bugs.passt.top/show_bug.cgi?id=179 confirms this series solves the issue, and delaying this further doesn't sound like a good idea, so I went ahead and finally applied this, fixing a trivial conflict with 812cdb802c6e ("tcp: Move tap header update out of tcp_fill_headers()") on the way.

Makes sense to me. -- David Gibson (he or they) | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you, not the other way | around. http://www.ozlabs.org/~dgibson