+ mm-page-writeback-support-tail-pages-in-wait_for_stable_page.patch added to -mm tree

[akpm@linux-foundation.org]

The patch titled
     Subject: mm/page-writeback: support tail pages in wait_for_stable_page
has been added to the -mm tree.  Its filename is
     mm-page-writeback-support-tail-pages-in-wait_for_stable_page.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-page-writeback-support-tail-pages-in-wait_for_stable_page.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-page-writeback-support-tail-pages-in-wait_for_stable_page.patch

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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Subject: mm/page-writeback: support tail pages in wait_for_stable_page

page->mapping is undefined for tail pages, so operate exclusively on the
head page.

Link: https://lkml.kernel.org/r/20200908195539.25896-11-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/page-writeback.c |    1 +
 1 file changed, 1 insertion(+)

--- a/mm/page-writeback.c~mm-page-writeback-support-tail-pages-in-wait_for_stable_page
+++ a/mm/page-writeback.c
@@ -2849,6 +2849,7 @@ EXPORT_SYMBOL_GPL(wait_on_page_writeback
  */
 void wait_for_stable_page(struct page *page)
 {
+	page = thp_head(page);
 	if (bdi_cap_stable_pages_required(inode_to_bdi(page->mapping->host)))
 		wait_on_page_writeback(page);
 }
_

Patches currently in -mm which might be from willy@infradead.org are

mm-debug-do-not-dereference-i_ino-blindly.patch
mm-account-pmd-tables-like-pte-tables.patch
mm-move-pagedoublemap-bit.patch
mm-simplify-pagedoublemap-with-pf_second-policy.patch
xarray-add-xa_get_order.patch
xarray-add-xas_split.patch
mm-filemap-fix-storing-to-a-thp-shadow-entry.patch
mm-filemap-fix-page-cache-removal-for-arbitrary-sized-thps.patch
mm-memory-remove-page-fault-assumption-of-compound-page-size.patch
mm-page_owner-change-split_page_owner-to-take-a-count.patch
mm-huge_memory-fix-page_trans_huge_mapcount-assumption-of-thp-size.patch
mm-huge_memory-fix-can_split_huge_page-assumption-of-thp-size.patch
mm-rmap-fix-assumptions-of-thp-size.patch
mm-truncate-fix-truncation-for-pages-of-arbitrary-size.patch
mm-page-writeback-support-tail-pages-in-wait_for_stable_page.patch
mm-vmscan-allow-arbitrary-sized-pages-to-be-paged-out.patch
mm-readahead-add-define_readahead.patch
mm-readahead-make-page_cache_ra_unbounded-take-a-readahead_control.patch
mm-readahead-make-do_page_cache_ra-take-a-readahead_control.patch
mm-readahead-add-page_cache_sync_ra-and-page_cache_async_ra.patch
harden-autofs-ioctl-table.patch