From 04b177544a040cbafab760d6b766381c6b22e0a8 Mon Sep 17 00:00:00 2001 From: Matthew Brost Date: Tue, 21 Jul 2026 15:32:44 -0700 Subject: [PATCH] drm/pagemap: Guard HPAGE_PMD_ORDER use with CONFIG_ARCH_ENABLE_THP_MIGRATION HPAGE_PMD_SHIFT expands to BUILD_BUG() when CONFIG_PGTABLE_HAS_HUGE_LEAVES is not set, causing a compile error when both CONFIG_TRANSPARENT_HUGEPAGE and CONFIG_HUGETLB_PAGE are disabled: drivers/gpu/drm/drm_pagemap.c:480:12: error: call to '__compiletime_assert_458' declared with 'error' attribute: BUILD_BUG failed 480 | order = HPAGE_PMD_ORDER; | ^ include/linux/huge_mm.h:117:26: note: expanded from macro 'HPAGE_PMD_ORDER' 117 | #define HPAGE_PMD_ORDER (HPAGE_PMD_SHIFT-PAGE_SHIFT) | ^ include/linux/huge_mm.h:113:28: note: expanded from macro 'HPAGE_PMD_SHIFT' 113 | #define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; }) Define DRM_PAGEMAP_PMD_ORDER, which maps to HPAGE_PMD_ORDER when CONFIG_ARCH_ENABLE_THP_MIGRATION is enabled and to -1 otherwise. This is safe because all code paths that use DRM_PAGEMAP_PMD_ORDER are reachable only when CONFIG_ARCH_ENABLE_THP_MIGRATION is enabled. Fixes: 139ab31aea8a ("drm/pagemap: Correct cpages calculation for migrate_vma_setup") Reported-by: kernel test robot Closes: https://lore.kernel.org/r/202607201914.LpAGsbXs-lkp@intel.com/ Cc: Jan Stancek Cc: stable@vger.kernel.org Signed-off-by: Matthew Brost Tested-by: Jan Stancek Reviewed-by: Himal Prasad Ghimiray Link: https://patch.msgid.link/20260721223244.1102276-1-matthew.brost@intel.com --- drivers/gpu/drm/drm_pagemap.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/drm_pagemap.c b/drivers/gpu/drm/drm_pagemap.c index 892b325fa99b..4a794544b7dc 100644 --- a/drivers/gpu/drm/drm_pagemap.c +++ b/drivers/gpu/drm/drm_pagemap.c @@ -12,6 +12,12 @@ #include #include +#if IS_ENABLED(CONFIG_ARCH_ENABLE_THP_MIGRATION) +#define DRM_PAGEMAP_PMD_ORDER HPAGE_PMD_ORDER +#else +#define DRM_PAGEMAP_PMD_ORDER (-1) +#endif + /** * DOC: Overview * @@ -579,7 +585,7 @@ static int drm_pagemap_cpages(unsigned long *migrate_pfn, unsigned long npages) order = folio_order(folio); cpages += NR_PAGES(order); } else if (migrate_pfn[i] & MIGRATE_PFN_COMPOUND) { - order = HPAGE_PMD_ORDER; + order = DRM_PAGEMAP_PMD_ORDER; cpages += NR_PAGES(order); } @@ -767,10 +773,11 @@ int drm_pagemap_migrate_to_devmem(struct drm_pagemap_devmem *devmem_allocation, if (migrate.src[i] & MIGRATE_PFN_COMPOUND) { drm_WARN_ONCE(dpagemap->drm, src_page && - folio_order(page_folio(src_page)) != HPAGE_PMD_ORDER, + folio_order(page_folio(src_page)) != + DRM_PAGEMAP_PMD_ORDER, "Unexpected folio order\n"); - order = HPAGE_PMD_ORDER; + order = DRM_PAGEMAP_PMD_ORDER; migrate.dst[i] |= MIGRATE_PFN_COMPOUND; for (j = 1; j < NR_PAGES(order) && i + j < npages; j++)