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Date:   Wed, 26 Jan 2022 21:28:46 +0000
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Subject: Re: [PATCH for-next v4] cgroup/bpf: fast path skb BPF filtering
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To:     Martin KaFai Lau <kafai@fb.com>
Cc:     netdev@vger.kernel.org, bpf@vger.kernel.org,
        Alexei Starovoitov <ast@kernel.org>,
        Andrii Nakryiko <andrii@kernel.org>,
        Song Liu <songliubraving@fb.com>, linux-kernel@vger.kernel.org,
        Stanislav Fomichev <sdf@google.com>
References: <94e36de3cc2b579e45f95c189a6f5378bf1480ac.1643156174.git.asml.silence@gmail.com>
 <20220126203055.3xre2m276g2q2tkx@kafai-mbp.dhcp.thefacebook.com>
From:   Pavel Begunkov <asml.silence@gmail.com>
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On 1/26/22 20:30, Martin KaFai Lau wrote:
> On Wed, Jan 26, 2022 at 12:22:13AM +0000, Pavel Begunkov wrote:
>>   #define BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb)			      \
>>   ({									      \
>>   	int __ret = 0;							      \
>> -	if (cgroup_bpf_enabled(CGROUP_INET_INGRESS))		      \
>> +	if (cgroup_bpf_enabled(CGROUP_INET_INGRESS) && sk &&		      \
>  From reading sk_filter_trim_cap() where this will be called, sk cannot be NULL.
> If yes, the new sk test is not needed.

Well, there is no sane way to verify how it's used considering

EXPORT_SYMBOL(__cgroup_bpf_run_filter_skb);

but can remove the check if nobody cares


> Others lgtm.
> 
>> +	    cgroup_bpf_sock_enabled(sk, CGROUP_INET_INGRESS)) 	      \
>>   		__ret = __cgroup_bpf_run_filter_skb(sk, skb,		      \
>>   						    CGROUP_INET_INGRESS); \
>>   									      \

-- 
Pavel Begunkov