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Message-ID: <a127720d-ed49-5d20-4d63-13da8914652d@redhat.com>
Date:   Tue, 20 Sep 2022 10:19:23 +0200
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Subject: Re: [PATCH 3/3] debugfs: fix error when writing negative value to
 atomic_t debugfs file
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To:     Akinobu Mita <akinobu.mita@gmail.com>, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        linux-kselftest@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        corbet@lwn.net, osalvador@suse.de, shuah@kernel.org,
        Zhao Gongyi <zhaogongyi@huawei.com>,
        Wei Yongjun <weiyongjun1@huawei.com>,
        Yicong Yang <yangyicong@hisilicon.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        akpm@linux-foundation.org
References: <20220919172418.45257-1-akinobu.mita@gmail.com>
 <20220919172418.45257-4-akinobu.mita@gmail.com>
From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat
In-Reply-To: <20220919172418.45257-4-akinobu.mita@gmail.com>
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On 19.09.22 19:24, Akinobu Mita wrote:
> The simple attribute files do not accept a negative value since the
> commit 488dac0c9237 ("libfs: fix error cast of negative value in
> simple_attr_write()"), so we have to use a 64-bit value to write a
> negative value for a debugfs file created by debugfs_create_atomic_t().

Is that comment stale?

I would ahve thought you simply document that we restore the original 
behavior essentially by reverting 005747526d4f ("docs: fault-injection: 
fix non-working usage of negative values") and the using 
DEFINE_DEBUGFS_ATTRIBUTE_SIGNED accordingly.

> 
> This restores the previous behaviour by introducing
> DEFINE_DEBUGFS_ATTRIBUTE_SIGNED for a signed value.
> 
> Fixes: 488dac0c9237 ("libfs: fix error cast of negative value in simple_attr_write()")
> Reported-by: Zhao Gongyi <zhaogongyi@huawei.com>
> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>


Apart from that

Reviewed-by: David Hildenbrand <david@redhat.com>

-- 
Thanks,

David / dhildenb