On Sun, May 30, 2021 at 10:14:22PM +0100, Matthew Wilcox wrote:

On Sun, May 30, 2021 at 12:13:05PM -0700, Nathan Chancellor wrote:

quoted

Hi Matthew,

On Wed, Mar 10, 2021 at 06:55:30PM +0000, Matthew Wilcox (Oracle) wrote:

quoted

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 <redacted>

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.

Uh that patch didn't get cc'ed to any list so I've ignored it. I've found
it now, but lack of lore link is awkward. Can you pls resubmit with
dri-devel on cc? fbdev list is dead, I don't look there.

Thanks, Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch