diff options
| author | David Hildenbrand <david@redhat.com> | 2024-04-09 21:22:51 +0200 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2024-05-05 17:53:29 -0700 |
| commit | 0a7bda48012b521579898fca1fc157c53014afee (patch) | |
| tree | c46f2953c6e3dd7811e32e157537b8d074cd3bdc /mm/huge_memory.c | |
| parent | 3aeea4fc835d31235947787c2b8dcbc255131106 (diff) | |
mm/huge_memory: use folio_mapcount() in zap_huge_pmd() sanity check
We want to limit the use of page_mapcount() to the places where it is
absolutely necessary. Let's similarly check for folio_mapcount()
underflows instead of page_mapcount() underflows like we do in
zap_present_folio_ptes() now.
Instead of the VM_BUG_ON(), we should actually be doing something like
print_bad_pte(). For now, let's keep it simple and use WARN_ON_ONCE(),
performing that check independently of DEBUG_VM.
Link: https://lkml.kernel.org/r/20240409192301.907377-9-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Richard Chang <richardycc@google.com>
Cc: Rich Felker <dalias@libc.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yin Fengwei <fengwei.yin@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/huge_memory.c')
| -rw-r--r-- | mm/huge_memory.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 14f04fbc22d9..3ad76f23fadd 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1791,7 +1791,7 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, folio = page_folio(page); folio_remove_rmap_pmd(folio, page, vma); - VM_BUG_ON_PAGE(page_mapcount(page) < 0, page); + WARN_ON_ONCE(folio_mapcount(folio) < 0); VM_BUG_ON_PAGE(!PageHead(page), page); } else if (thp_migration_supported()) { swp_entry_t entry; |