Re: linux-next: manual merge of the mm-unstable tree with the drm-misc-fixes tree

[Matthew Brost]

On Mon, Jul 20, 2026 at 03:46:00PM +0100, Matthew Wilcox wrote:
> On Mon, Jul 20, 2026 at 04:41:41PM +0200, Christoph Hellwig wrote:
> > >   /**
> > >  - * ttm_backup_backup_page() - Backup a page
> > >  + * ttm_backup_backup_folio() - Backup a folio
> > >    * @backup: The struct backup pointer to use.
> > >  - * @page: The page to back up.
> > >  - * @writeback: Whether to perform immediate writeback of the page.
> > >  + * @folio: The folio to back up.
> > >  + * @order: The allocation order of @folio.  Since TTM allocates higher-order
> > >  + *         pages without __GFP_COMP, folio_nr_pages(@folio) would always
> > >  + *         return 1; the caller must pass the true order explicitly.
> 
> Wait, what?  This is just broken.  TTM should change to allocate using
> GFP_COMP.  Why can't graphics people ask questions before writing stupid
> patches?
> 

To be honest, I have no idea why TTM doesn't set GFP_COMP. This
predates my work in graphics by nearly a decade.

I found the following comment in TTM, which was added in this patch:
`git format-patch -1 bf9eee249ac20`

As far as I can tell, setting GFP_COMP would make things a lot easier in
a number of places.

Christian, who maintains TTM, is out for a couple of weeks, but this is
something we should probably take a closer look at.

Sorry for sending a stupid patch.

Matt