From 12b2285bf3d14372238d36215b73af02ac3bdfc1 Mon Sep 17 00:00:00 2001 From: Matthew Brost Date: Fri, 16 Jan 2026 12:10:16 +0100 Subject: mm/zone_device: reinitialize large zone device private folios MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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. Without this fix, individual pages could have invalid pgmap fields and flags (with PG_locked being notably problematic) due to prior different order allocations, which can, and will, result in kernel crashes. Link: https://lkml.kernel.org/r/20260116111325.1736137-2-francois.dugast@intel.com Fixes: d245f9b4ab80 ("mm/zone_device: support large zone device private folios") Signed-off-by: Matthew Brost Signed-off-by: Francois Dugast Acked-by: Felix Kuehling Reviewed-by: Balbir Singh Acked-by: Vlastimil Babka Cc: Zi Yan Cc: Alistair Popple Cc: Madhavan Srinivasan Cc: Nicholas Piggin Cc: Michael Ellerman Cc: "Christophe Leroy (CS GROUP)" Cc: Alex Deucher Cc: "Christian König" Cc: David Airlie Cc: Simona Vetter Cc: Maarten Lankhorst Cc: Maxime Ripard Cc: Thomas Zimmermann Cc: Lyude Paul Cc: Danilo Krummrich Cc: David Hildenbrand Cc: Oscar Salvador Cc: Andrew Morton Cc: Jason Gunthorpe Cc: Leon Romanovsky Cc: Lorenzo Stoakes Cc: Liam R. Howlett Cc: Mike Rapoport Cc: Suren Baghdasaryan Cc: Michal Hocko Signed-off-by: Andrew Morton --- arch/powerpc/kvm/book3s_hv_uvmem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/powerpc') diff --git a/arch/powerpc/kvm/book3s_hv_uvmem.c b/arch/powerpc/kvm/book3s_hv_uvmem.c index e5000bef90f2..7cf9310de0ec 100644 --- a/arch/powerpc/kvm/book3s_hv_uvmem.c +++ b/arch/powerpc/kvm/book3s_hv_uvmem.c @@ -723,7 +723,7 @@ static struct page *kvmppc_uvmem_get_page(unsigned long gpa, struct kvm *kvm) dpage = pfn_to_page(uvmem_pfn); dpage->zone_device_data = pvt; - zone_device_page_init(dpage, 0); + zone_device_page_init(dpage, &kvmppc_uvmem_pgmap, 0); return dpage; out_clear: spin_lock(&kvmppc_uvmem_bitmap_lock); -- cgit v1.2.3