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From:   Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To:     Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= <toke@redhat.com>
Cc:     netdev@vger.kernel.org, bpf@vger.kernel.org,
        Alexei Starovoitov <ast@kernel.org>,
        Andrii Nakryiko <andrii@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        "David S. Miller" <davem@davemloft.net>,
        Ingo Molnar <mingo@redhat.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Jesper Dangaard Brouer <hawk@kernel.org>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@kernel.org>, Martin KaFai Lau <kafai@fb.com>,
        Song Liu <songliubraving@fb.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Yonghong Song <yhs@fb.com>
Subject: Re: [PATCH net] xdp: xdp_mem_allocator can be NULL in
 trace_mem_connect().
Message-ID: <YiZIEVTRMQVYe8DP@linutronix.de>
References: <YiC0BwndXiwxGDNz@linutronix.de>
 <875yovdtm4.fsf@toke.dk>
 <YiDM0WRlWuM2jjNJ@linutronix.de>
 <87y21l7lmr.fsf@toke.dk>
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On 2022-03-07 17:50:04 [+0100], Toke H=C3=B8iland-J=C3=B8rgensen wrote:
>=20
> Right, looking at the code again, the id is only assigned in the path
> that doesn't return NULL from __xdp_reg_mem_model().
>=20
> Given that the trace points were put in specifically to be able to pair
> connect/disconnect using the IDs, I don't think there's any use to
> creating the events if there's no ID, so I think we should fix it by
> skipping the trace event entirely if xdp_alloc is NULL.

This sounds like a reasonable explanation. If nobody disagrees then I
post a new patch tomorrow and try to recycle some of what you wrote :)

> -Toke

Sebastian