[PATCH v5 1/5] mm/zone_device: Reinitialize large zone device private folios

[Matthew Brost]

On Wed, Jan 14, 2026 at 07:07:37PM -0800, Matthew Brost wrote:
> On Wed, Jan 14, 2026 at 07:01:54PM -0800, Andrew Morton wrote:
> > On Wed, 14 Jan 2026 20:19:52 +0100 Francois Dugast <francois.dugast at intel.com> wrote:
> > 
> > > From: Matthew Brost <matthew.brost at intel.com>
> > > 
> > > Reinitialize metadata for large zone device private folios in
> > > zone_device_page_init prior to creating a higher-order zone device
> > > private folio. This step is necessary when the folio’s order changes
> > > dynamically between zone_device_page_init calls to avoid building a
> > > corrupt folio. As part of the metadata reinitialization, the dev_pagemap
> > > must be passed in from the caller because the pgmap stored in the folio
> > > page may have been overwritten with a compound head.
> > > 
> > > --- a/drivers/gpu/drm/drm_pagemap.c
> > > +++ b/drivers/gpu/drm/drm_pagemap.c
> > > @@ -201,7 +201,7 @@ static void drm_pagemap_get_devmem_page(struct page *page,
> > >  					struct drm_pagemap_zdd *zdd)
> > >  {
> > >  	page->zone_device_data = drm_pagemap_zdd_get(zdd);
> > > -	zone_device_page_init(page, 0);
> > > +	zone_device_page_init(page, zdd->dpagemap->pagemap, 0);
> > >  }
> > 
> > drivers/gpu/drm/drm_pagemap.c:200:40: error: 'struct drm_pagemap_zdd' has no member named 'dpagemap'
> > 
> > I guess this was accidentally fixed in a later patch?
> > 
> 
> Ah, no. This is because we merged some in drm-tip which is not 6.19,
> this is based on the drm-tip branch.
> 
> > Please let's decide whether to fast-track the [1/N] fix into mainline
> > and if so, prepare something which compiles!
> 
> Maybe we just take this through the MM repo then? I suppose I should
> send out patch which applies to the MM repo? I just cloned that repo.
> 

Sorry, typing to fast. I believe have a patch structure that applies to
6.19, MM branches, and drm-tip. Just need to run CI on 3 branches :).

Matt

> Matt