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Date:   Thu, 28 Feb 2019 16:54:03 +0300
From:   Dan Carpenter <dan.carpenter@oracle.com>
To:     Brendan Higgins <brendanhiggins@google.com>
Cc:     Stephen Boyd <sboyd@kernel.org>,
        Frank Rowand <frowand.list@gmail.com>,
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Subject: Re: [RFC v4 08/17] kunit: test: add support for test abort
Message-ID: <20190228135403.GD9806@kadam>
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On Thu, Feb 28, 2019 at 01:03:24AM -0800, Brendan Higgins wrote:
> you could do:
> 
> if (IS_ERR_OR_NULL(ptr)) {
>         KUNIT_FAIL(test, "ptr is an errno or null: %ld", ptr);
>         return;
> }

It's best to not mix error pointers and NULL but when we do mix them,
it means that NULL is a special kind of success.  Like we try to load
a feature and we get back:

    valid pointer <-- success
    null          <-- feature is disabled.  not an error.
    error pointer <-- feature is broken.  fail.

regards,
dan carpenter