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Date: Mon, 1 Jul 2024 16:38:26 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Jakub Sitnicki <jakub@cloudflare.com>
Cc: netdev@vger.kernel.org, kernel-team@cloudflare.com
Subject: Re: [FYI] Input route ref count underflow since probably 6.6.22
Message-ID: <20240701163826.76558147@kernel.org>
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On Fri, 28 Jun 2024 13:10:53 +0200 Jakub Sitnicki wrote:
> We've observed an unbalanced dst_release() on an input route in v6.6.y.
> First noticed in 6.6.22. Or at least that is how far back our logs go.
> 
> We have just started looking into it and don't have much context yet,
> except that:
> 
> 1. the issue is architecture agnostic, seen both on x86_64 and arm64;
> 2. the backtrace, we realize, doesn't point to the source of problem,
>    it's just where the ref count underflow manifests itself;
> 3. while have out-of-tree modules, they are for the crypto subsystem.
> 
> We will follow up as we collect more info on this, but we would
> appreciate any hints or pointers to potential suspects, if anything
> comes to mind.

Hi! Luck would have it the same crash landed on my desk.
Did you manage to narrow it down?