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Subject: Re: [PATCH] drm/bridge: ti-sn65dsi83: Fix null pointer dereference in
 remove callback
To:     Jonathan Liu <net147@gmail.com>,
        Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc:     dri-devel <dri-devel@lists.freedesktop.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Andrzej Hajda <a.hajda@samsung.com>,
        Neil Armstrong <narmstrong@baylibre.com>,
        Robert Foss <robert.foss@linaro.org>,
        Jonas Karlman <jonas@kwiboo.se>,
        Jernej Skrabec <jernej.skrabec@gmail.com>,
        David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>,
        Linus Walleij <linus.walleij@linaro.org>,
        Frieder Schrempf <frieder.schrempf@kontron.de>
References: <20210617111925.162120-1-net147@gmail.com>
 <YMtYoaSIIRhb85fh@pendragon.ideasonboard.com>
 <CANwerB0J9xKj3kjYPjzfeDvKV8JXPcDtoZaLMzkudCBz8=ZnVw@mail.gmail.com>
From:   Marek Vasut <marex@denx.de>
Message-ID: <d708823a-3b28-2541-da06-86eb41484aaa@denx.de>
Date:   Fri, 18 Jun 2021 07:40:41 +0200
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On 6/18/21 5:06 AM, Jonathan Liu wrote:
> Hi Marek,

Hi,

>> Hi Jonathan,
>>
>> Thank you for the patch.
>>
>> On Thu, Jun 17, 2021 at 09:19:25PM +1000, Jonathan Liu wrote:
>>> If attach has not been called, unloading the driver can result in a null
>>> pointer dereference in mipi_dsi_detach as ctx->dsi has not been assigned
>>> yet.
>>
>> Shouldn't this be done in a brige .detach() operation instead ?
>>
> 
> Could you please take a look?
> I don't have a working setup to test moving the code to detach.

I just replied to your other email regarding bringing the chip up, so 
please bring your setup up first, then test this patch again, and then 
let's revisit this topic.