From: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Date: Fri, 20 Mar 2026 18:07:23 +0000 (+0000)
Subject: mm/huge_memory: remove unnecessary VM_BUG_ON_PAGE()
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=07f264680ac875725ca12e6adadd9e3def2e30f2;p=thirdparty%2Fkernel%2Flinux.git

mm/huge_memory: remove unnecessary VM_BUG_ON_PAGE()

This has been around since the beginnings of the THP implementation.  I
think we can safely assume that, if we have a THP folio, it will have a
head page.

Link: https://lkml.kernel.org/r/f3fa8eb4634ccb2e78209f570cc1a769a02ce93e.1774029655.git.ljs@kernel.org
Signed-off-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nico Pache <npache@redhat.com>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 283685dd6d9fe..f072acd5b2799 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2452,7 +2452,6 @@ bool zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
 		folio = page_folio(page);
 		folio_remove_rmap_pmd(folio, page, vma);
 		WARN_ON_ONCE(folio_mapcount(folio) < 0);
-		VM_BUG_ON_PAGE(!PageHead(page), page);
 	} else if (pmd_is_valid_softleaf(orig_pmd)) {
 		const softleaf_t entry = softleaf_from_pmd(orig_pmd);