From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx> 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@xxxxxxxxxxxxx Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> Reviewed-by: SeongJae Park <sjpark@xxxxxxxxx> Cc: Huang Ying <ying.huang@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- 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 (page->mapping->host->i_sb->s_iflags & SB_I_STABLE_WRITES) wait_on_page_writeback(page); } _
