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Date:   Wed, 14 Aug 2019 13:19:57 +0300
From:   Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
To:     Yonghong Song <yhs@fb.com>
Cc:     "magnus.karlsson@intel.com" <magnus.karlsson@intel.com>,
        "bjorn.topel@intel.com" <bjorn.topel@intel.com>,
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        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH bpf-next 1/3] libbpf: add asm/unistd.h to xsk to get
 __NR_mmap2
Message-ID: <20190814101955.GB4142@khorivan>
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References: <20190813102318.5521-1-ivan.khoronzhuk@linaro.org>
 <20190813102318.5521-2-ivan.khoronzhuk@linaro.org>
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On Wed, Aug 14, 2019 at 12:32:41AM +0000, Yonghong Song wrote:

Hi, Yonghong Song

>
>
>On 8/13/19 3:23 AM, Ivan Khoronzhuk wrote:
>> That's needed to get __NR_mmap2 when mmap2 syscall is used.
>
>It seems I did not have this issue on x64 machine e.g., Fedora 29.
>My glibc version is 2.28. gcc 8.2.1.

On 64 there is no the issue.

>
>What is your particular system glibc version?
>So needing kernel asm/unistd.h is because of older glibc on your
>system, or something else? Could you clarify?

It doesn't fix build issues, only runtime one on 32bits.

If no such inclusion -> no __NR_mmap2 definition - just mmap() is used ->
no problems on x64.

Is the inclusion -> no NR_mmap2 or is NR_mmap2 -> no problems on x64


-- 
Regards,
Ivan Khoronzhuk