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Subject: Re: [PATCH v2] dma-buf: heaps: init heaps in subsys_initcall
To:     John Stultz <john.stultz@linaro.org>,
        Shuosheng Huang <huangshuosheng@allwinnertech.com>
Cc:     Sumit Semwal <sumit.semwal@linaro.org>,
        Liam Mark <lmark@codeaurora.org>,
        Laura Abbott <labbott@redhat.com>,
        Brian Starkey <Brian.Starkey@arm.com>,
        linux-media <linux-media@vger.kernel.org>,
        dri-devel <dri-devel@lists.freedesktop.org>,
        lkml <linux-kernel@vger.kernel.org>
References: <20211022014850.22933-1-huangshuosheng@allwinnertech.com>
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From:   =?UTF-8?Q?Christian_K=c3=b6nig?= <christian.koenig@amd.com>
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Date:   Fri, 22 Oct 2021 08:32:45 +0200
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Am 22.10.21 um 04:56 schrieb John Stultz:
> On Thu, Oct 21, 2021 at 6:49 PM Shuosheng Huang
> <huangshuosheng@allwinnertech.com> wrote:
>> Some built-in modules will failed to use dma-buf heap to allocate
>> memory if the heap drivers are too late to be initialized.
>> To fix this issue, move initialization of dma-buf heap drivers in
>> subsys_initcall() which is more earlier to be called.
> Hey! Thanks so much for sending this out! I appreciate it!
>
> So the change looks pretty straightforward to me, however, the
> rationale for it is where we hit problems.
>
> With the upstream kernel, there are not yet any modules that directly
> allocate from dmabuf heaps. So in the context of the upstream kernel,
> the reasoning doesn't make much sense.

I was already wondering which driver does that.

> Now, I know folks have their own drivers that want to allocate from
> dmabuf heaps, but those haven't been submitted upstream yet.
> So maybe can you submit those patches that need this along with this
> change so it would make sense as part of a patch series? It would be
> trivial to justify including this patch then.

Yes, agree. This patch here alone has no justification to be upstream.

Regards,
Christian.

>
> thanks
> -john