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Date:   Wed, 10 Jul 2019 16:14:39 -0700
From:   Andi Kleen <ak@linux.intel.com>
To:     Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc:     Paolo Pisati <p.pisati@gmail.com>, Yonghong Song <yhs@fb.com>,
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Subject: Re: [RESEND] test_verifier #13 fails on arm64: "retval 65507 != -29"
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> > Reading csum_partial/csum_fold, seems like after calculation of
> > checksum (so-called unfolded checksum), it is supposed to be passed
> > into csum_fold() to convert it into 16-bit one and invert.

Yes, you always need to fold at the end.

The low level code does fold sometimes, but not always.

-Andi