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Subject: Re: [PATCH v2] fb_defio: Remove custom address_space_operations
To:     Matthew Wilcox <willy@infradead.org>
Cc:     dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org,
        William Kucharski <william.kucharski@oracle.com>,
        Jani Nikula <jani.nikula@intel.com>,
        Daniel Vetter <daniel.vetter@ffwll.ch>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        Ian Campbell <ijc@hellion.org.uk>,
        linux-fsdevel@vger.kernel.org,
        Jaya Kumar <jayakumar.lkml@gmail.com>,
        Christoph Hellwig <hch@lst.de>
References: <20210310185530.1053320-1-willy@infradead.org>
 <YLPjwUUmHDRjyPpR@Ryzen-9-3900X.localdomain>
 <YLQALv2YENIDh77N@casper.infradead.org>
From:   Nathan Chancellor <nathan@kernel.org>
Message-ID: <2977064f-42d0-7b64-176d-9509c205bfc3@kernel.org>
Date:   Sun, 30 May 2021 15:40:44 -0700
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On 5/30/2021 2:14 PM, Matthew Wilcox wrote:
> On Sun, May 30, 2021 at 12:13:05PM -0700, Nathan Chancellor wrote:
>> Hi Matthew,
>>
>> On Wed, Mar 10, 2021 at 06:55:30PM +0000, Matthew Wilcox (Oracle) wrote:
>>> There's no need to give the page an address_space.  Leaving the
>>> page->mapping as NULL will cause the VM to handle set_page_dirty()
>>> the same way that it's handled now, and that was the only reason to
>>> set the address_space in the first place.
>>>
>>> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
>>> Reviewed-by: Christoph Hellwig <hch@lst.de>
>>> Reviewed-by: William Kucharski <william.kucharski@oracle.com>
>>
>> This patch in mainline as commit ccf953d8f3d6 ("fb_defio: Remove custom
>> address_space_operations") causes my Hyper-V based VM to no longer make
>> it to a graphical environment.
> 
> Hi Nathan,
> 
> Thanks for the report.  I sent Daniel a revert patch with a full
> explanation last week, which I assume he'll queue up for a pull soon.
> You can just git revert ccf953d8f3d6 for yourself until that shows up.
> Sorry for the inconvenience.
> 

Thank you for the quick response! I will keep an eye out for the patch 
while reverting it locally in the meantime.

Cheers,
Nathan