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Date:   Thu, 12 Jan 2023 21:14:05 -0800
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Subject: Re: [bpf-next v5 3/3] bpf: hash map, suppress false lockdep warning
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To:     Tonghao Zhang <tong@infragraf.org>
Cc:     Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Andrii Nakryiko <andrii@kernel.org>,
        Song Liu <song@kernel.org>, Yonghong Song <yhs@fb.com>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@kernel.org>,
        Stanislav Fomichev <sdf@google.com>,
        Hao Luo <haoluo@google.com>, Jiri Olsa <jolsa@kernel.org>,
        Hou Tao <houtao1@huawei.com>, bpf@vger.kernel.org
References: <20230111092903.92389-1-tong@infragraf.org>
 <20230111092903.92389-3-tong@infragraf.org>
 <7e6d02ea-f9f7-2d09-bf10-ccd41b16a671@linux.dev>
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From:   Martin KaFai Lau <martin.lau@linux.dev>
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On 1/12/23 6:17 PM, Tonghao Zhang wrote:
>> I am not very sure about the lockdep_off/on. Other than the false warning when using the very same htab map by both NMI and non-NMI context, I think the lockdep will still be useful
> Agree, but there is no good way to fix this warning.

I applied patch 1 to the bpf tree with the 'Fixes: 20b6cc34ea74 ("bpf: Avoid 
hashtab deadlock with map_locked")' tag. Thanks.

The commit message has a link to the test. Not ideal but keeping the lockdep is 
more important.