Re: [PATCH rcu] configs/debug: make sure PROVE_RCU_LIST=y takes effect

[Matthieu Baerts <matttbe@kernel.org>]

Hi Jakub,

On 16/10/2024 03:11, Jakub Kicinski wrote:
> Commit 0aaa8977acbf ("configs: introduce debug.config for CI-like setup")
> added CONFIG_PROVE_RCU_LIST=y to the common CI config,
> but RCU_EXPERT is not set, and it's a dependency for
> CONFIG_PROVE_RCU_LIST=y. Make sure CIs take advantage
> of CONFIG_PROVE_RCU_LIST=y, recent fixes in networking
> indicate that it does catch bugs.

Good catch! I confirm it fixes the issue:

Acked-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>

> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
> ---
> I'd be slightly tempted to still send it to Linux for v6.12.

Good idea, it sounds like a fix because I guess if it was on the list,
it was supposed to be used. But be careful it might detect quite a few
issues: I just enabled it on MPTCP tree, and it found issues.

It might be good to check the impact first, e.g. at least enabling it
when running the Networking tests. Please note that the CI didn't pick
up this patch, because it is marked for RCU (PATCH rcu):


https://patchwork.kernel.org/project/netdevbpf/patch/20241016011144.3058445-1-kuba@kernel.org/

If the impact is important, it might be better to target linux-next
first, no?

Cheers,
Matt
-- 
Sponsored by the NGI0 Core fund.