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Date:   Wed, 3 Aug 2022 08:37:06 -0700
From:   Martin KaFai Lau <kafai@fb.com>
To:     Jakub Kicinski <kuba@kernel.org>
Cc:     Hawkins Jiawei <yin31149@gmail.com>,
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        Wen Gu <guwen@linux.alibaba.com>
Subject: Re: [PATCH v4] net: fix refcount bug in sk_psock_get (2)
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On Wed, Aug 03, 2022 at 08:14:13AM -0700, Jakub Kicinski wrote:
> On Wed,  3 Aug 2022 20:41:22 +0800 Hawkins Jiawei wrote:
> > -/* Pointer stored in sk_user_data might not be suitable for copying
> > - * when cloning the socket. For instance, it can point to a reference
> > - * counted object. sk_user_data bottom bit is set if pointer must not
> > - * be copied.
> > +/* flag bits in sk_user_data
> > + *
> > + * SK_USER_DATA_NOCOPY - Pointer stored in sk_user_data might
> > + * not be suitable for copying when cloning the socket.
> > + * For instance, it can point to a reference counted object.
> > + * sk_user_data bottom bit is set if pointer must not be copied.
> > + *
> > + * SK_USER_DATA_BPF    - Managed by BPF
> 
> I'd use this opportunity to add more info here, BPF is too general.
> Maybe "Pointer is used by a BPF reuseport array"? Martin, WDYT?
SGTM.  Thanks.