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Date: Mon, 28 Mar 2022 11:51:53 +0200
From: Florian Westphal <fw@strlen.de>
To: Geliang Tang <geliang.tang@suse.com>
Cc: mptcp@lists.linux.dev
Subject: Re: [PATCH mptcp-next v7 4/8] mptcp: add sched in mptcp_sock
Message-ID: <20220328095153.GC18687@breakpoint.cc>
References: <cover.1648459865.git.geliang.tang@suse.com>
 <2812381119c23048dadbf5372293c724ff4b7970.1648459865.git.geliang.tang@suse.com>
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User-Agent: Mutt/1.10.1 (2018-07-13)

Geliang Tang <geliang.tang@suse.com> wrote:
> +void mptcp_release_sched(struct mptcp_sock *msk)
> +{
> +	if (msk->sched && msk->sched->release)
> +		msk->sched->release(msk);
> +	bpf_module_put(msk->sched, msk->sched->owner);
> +	msk->sched = NULL;

Strange.  First line makes sure we don't null deref on msk->sched ==
NULL, but bpf_module_put() passes msk->sched->owner?

Does bpf_module_put need to live in a 
if (msk->sched) { branch or is the null test redundant?