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Date:   Mon, 20 Jun 2022 11:48:08 -0700
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Subject: Re: [PATCH bpf-next v2 3/8] bpf, iter: Fix the condition on p when
 calling stop.
Content-Language: en-US
To:     Yosry Ahmed <yosryahmed@google.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Andrii Nakryiko <andrii@kernel.org>,
        Martin KaFai Lau <kafai@fb.com>,
        Song Liu <songliubraving@fb.com>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@kernel.org>, Hao Luo <haoluo@google.com>,
        Tejun Heo <tj@kernel.org>, Zefan Li <lizefan.x@bytedance.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Shuah Khan <shuah@kernel.org>, Michal Hocko <mhocko@kernel.org>
Cc:     Roman Gushchin <roman.gushchin@linux.dev>,
        David Rientjes <rientjes@google.com>,
        Stanislav Fomichev <sdf@google.com>,
        Greg Thelen <gthelen@google.com>,
        Shakeel Butt <shakeelb@google.com>,
        linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
        bpf@vger.kernel.org, cgroups@vger.kernel.org
References: <20220610194435.2268290-1-yosryahmed@google.com>
 <20220610194435.2268290-4-yosryahmed@google.com>
From:   Yonghong Song <yhs@fb.com>
In-Reply-To: <20220610194435.2268290-4-yosryahmed@google.com>
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On 6/10/22 12:44 PM, Yosry Ahmed wrote:
> From: Hao Luo <haoluo@google.com>
> 
> In bpf_seq_read, seq->op->next() could return an ERR and jump to
> the label stop. However, the existing code in stop does not handle
> the case when p (returned from next()) is an ERR. Adds the handling
> of ERR of p by converting p into an error and jumping to done.
> 
> Because all the current implementations do not have a case that
> returns ERR from next(), so this patch doesn't have behavior changes
> right now.
> 
> Signed-off-by: Hao Luo <haoluo@google.com>
> Signed-off-by: Yosry Ahmed <yosryahmed@google.com>

Acked-by: Yonghong Song <yhs@fb.com>