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Date:   Tue, 4 Apr 2023 06:22:50 -0700
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Subject: Re: [PATCH v3 07/11] iio: core: Add new DMABUF interface
 infrastructure
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To:     Paul Cercueil <paul@crapouillou.net>,
        =?UTF-8?Q?Nuno_S=c3=a1?= <noname.nuno@gmail.com>,
        Jonathan Cameron <jic23@kernel.org>,
        Vinod Koul <vkoul@kernel.org>,
        Michael Hennerich <Michael.Hennerich@analog.com>,
        Sumit Semwal <sumit.semwal@linaro.org>,
        =?UTF-8?Q?Christian_K=c3=b6nig?= <christian.koenig@amd.com>
Cc:     linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org,
        dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org,
        dmaengine@vger.kernel.org, linux-media@vger.kernel.org
References: <20230403154800.215924-1-paul@crapouillou.net>
 <20230403154800.215924-8-paul@crapouillou.net>
 <798e1ff0651da8e4b113d30bf8cec2a7a0e6898f.camel@gmail.com>
 <2dac030470ffe74b6d21a1e6510afcefaf58cd6a.camel@crapouillou.net>
From:   Lars-Peter Clausen <lars@metafoo.de>
In-Reply-To: <2dac030470ffe74b6d21a1e6510afcefaf58cd6a.camel@crapouillou.net>
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On 4/4/23 00:55, Paul Cercueil wrote:
> [...]
>>> +       priv = attach->importer_priv;
>>> +       list_del_init(&priv->entry);
>>> +
>>> +       iio_buffer_dmabuf_put(attach);
>>> +       iio_buffer_dmabuf_put(attach);
>>> +
>> Is this intended? Looks suspicious...
> It is intended, yes. You want to release the dma_buf_attachment that's
> created in iio_buffer_attach_dmabuf(), and you need to call
> iio_buffer_find_attachment() to get a pointer to it, which also gets a
> second reference - so it needs to unref twice.
Let's add a comment documenting that.