mm/huge_memory: check new folio order when split a folio
authorZi Yan <ziy@nvidia.com>
Thu, 7 Mar 2024 18:18:53 +0000 (13:18 -0500)
committerAndrew Morton <akpm@linux-foundation.org>
Tue, 12 Mar 2024 20:07:17 +0000 (13:07 -0700)
commit1412ecb3d256e5d23c6bd150e110cef6e3736844
tree3b4c9319b1ae4ef6a92f77669a9d79dc0d240dc3
parentd221dd5fea6415cc6c7acb7d68c8e5dfd61c3902
mm/huge_memory: check new folio order when split a folio

A folio can only be split into lower orders.

Since there are no new_order checks in debugfs, any new_order can be
passed via debugfs into split_huge_page_to_list_to_order().

Check new_order to make sure it is smaller than input folio order.

Link: https://lkml.kernel.org/r/20240307181854.138928-1-zi.yan@sent.com
Fixes: c010d47f107f ("mm: thp: split huge page to any lower order pages")
Signed-off-by: Zi Yan <ziy@nvidia.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/linux-mm/7dda9283-b437-4cf8-ab0d-83c330deb9c0@moroto.mountain/
Cc: David Hildenbrand <david@redhat.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mm/huge_memory.c