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Date:   Mon, 7 Nov 2022 20:37:49 +0300
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Subject: Re: [PATCH v7 18/21] dma-buf: Move dma_buf_mmap() to dynamic locking
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To:     Daniel Vetter <daniel@ffwll.ch>
Cc:     David Airlie <airlied@linux.ie>, Gerd Hoffmann <kraxel@redhat.com>,
        Gurchetan Singh <gurchetansingh@chromium.org>,
        Chia-I Wu <olvaffe@gmail.com>,
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        =?UTF-8?Q?Christian_K=c3=b6nig?= <christian.koenig@amd.com>,
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        Ruhl Michael J <michael.j.ruhl@intel.com>,
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        Dmitry Osipenko <digetx@gmail.com>,
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References: <20221017172229.42269-1-dmitry.osipenko@collabora.com>
 <20221017172229.42269-19-dmitry.osipenko@collabora.com>
 <CAKMK7uFFwTfNYT2BrubYvUMrH4fEmtF=yJshUck3-gKYLGqxCg@mail.gmail.com>
From:   Dmitry Osipenko <dmitry.osipenko@collabora.com>
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On 11/7/22 20:25, Daniel Vetter wrote:
>> Move dma_buf_mmap() function to the dynamic locking specification by
>> taking the reservation lock. Neither of the today's drivers take the
>> reservation lock within the mmap() callback, hence it's safe to enforce
>> the locking.
>>
>> Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
>> Acked-by: Christian König <christian.koenig@amd.com>
>> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
> Just noticed this while reading code ... this patch seems to have
> missed dma_buf_mmap_internal()?
> 
> Might be good if at least some drivers gain a dma_resv_assert_held in
> that path to make sure we're not quite this bad, together with fixing
> this issue.

Good catch! I'll prepare the patches.

-- 
Best regards,
Dmitry