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Subject: Re: [PATCH] selftests/bpf: Add bpf_probe_read_str to bpf_helpers.h
To:     Tushar Dave <tushar.n.dave@oracle.com>, ast@kernel.org,
        shuah@kernel.org, netdev@vger.kernel.org,
        linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org
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 <f7ff30a7-888f-bb3c-b6b5-48c82d5b0c08@oracle.com>
From:   Daniel Borkmann <daniel@iogearbox.net>
Message-ID: <916737aa-6b2b-b207-a1ed-4751c8deca3b@iogearbox.net>
Date:   Wed, 28 Feb 2018 22:31:17 +0100
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On 02/28/2018 10:28 PM, Tushar Dave wrote:
> On 02/28/2018 08:57 AM, Daniel Borkmann wrote:
>> Hi Tushar,
>>
>> On 02/28/2018 01:33 AM, Tushar Dave wrote:
>>> Using bpf_probe_read_str() from samples/bpf causes compiler warning.
>>> e.g.
>>> warning: implicit declaration of function 'bpf_probe_read_str' is invalid in C99
>>>        [-Wimplicit-function-declaration]
>>>          num = bpf_probe_read_str(buf, sizeof(buf), ctx->di);
>>>                ^
>>> 1 warning generated.
>>>
>>> Add bpf_probe_read_str() to bpf_helpers.h so it can be used by
>>> samples/bpf programs.
>>>
>>> Signed-off-by: Tushar Dave <tushar.n.dave@oracle.com>
>>
>> In general no objections to it, but it would need an in-tree
>> user first:
>>
>> $ git grep -n bpf_probe_read_str tools/
>> tools/include/uapi/linux/bpf.h:596: * int bpf_probe_read_str(void *dst, int size, const void *unsafe_ptr)
>> $
>>
>> Why not adding this along with a sample?
> Okay, I will send new patch along with new sample or add usage of
> bpf_probe_read_str() in one of our exiting sample :)

Sounds great, the latter is totally fine as well. :-)

Thanks,
Daniel