The quilt patch titled
Subject: mm: assert the folio is locked in folio_start_writeback()
has been removed from the -mm tree. Its filename was
mm-assert-the-folio-is-locked-in-folio_start_writeback.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: mm: assert the folio is locked in folio_start_writeback()
Date: Wed, 26 Feb 2025 15:36:12 +0000
The folio must be locked when we start writeback in order to prevent
writeback from being started twice on the same folio. I don't expect this
to catch any problems, but it should be good documentation.
Link: https://lkml.kernel.org/r/20250226153614.3774896-1-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Reviewed-by: "Darrick J. Wong" <djwong@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/page-writeback.c | 1 +
1 file changed, 1 insertion(+)
--- a/mm/page-writeback.c~mm-assert-the-folio-is-locked-in-folio_start_writeback
+++ a/mm/page-writeback.c
@@ -3109,6 +3109,7 @@ void __folio_start_writeback(struct foli
int access_ret;
VM_BUG_ON_FOLIO(folio_test_writeback(folio), folio);
+ VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio);
if (mapping && mapping_use_writeback_tags(mapping)) {
XA_STATE(xas, &mapping->i_pages, folio_index(folio));
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
dax-remove-access-to-page-index.patch
dax-use-folios-more-widely-within-dax.patch
hugetlb-convert-hugetlb_vma_maps_page-to-hugetlb_vma_maps_pfn.patch
hugetlb-convert-adjust_range_hwpoison-to-take-a-folio.patch
mm-convert-lru_add_page_tail-to-lru_add_split_folio.patch
mm-separate-folio_split_memcg_refs-from-split_page_memcg.patch
mm-simplify-split_page_memcg.patch
mm-remove-references-to-folio-in-split_page_memcg.patch
mm-simplify-folio_memcg_charged.patch
mm-remove-references-to-folio-in-__memcg_kmem_uncharge_page.patch
ocfs2-use-memcpy_to_folio-in-ocfs2_symlink_get_block.patch
ocfs2-remove-reference-to-bh-b_page.patch
