The patch titled Subject: mm/huge_memory: fix can_split_huge_page assumption of THP size has been added to the -mm tree. Its filename is mm-huge_memory-fix-can_split_huge_page-assumption-of-thp-size.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/mm-huge_memory-fix-can_split_huge_page-assumption-of-thp-size.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/mm-huge_memory-fix-can_split_huge_page-assumption-of-thp-size.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx> Subject: mm/huge_memory: fix can_split_huge_page assumption of THP size Ask the page how many subpages it has instead of assuming it's PMD size. Link: https://lkml.kernel.org/r/20200908195539.25896-8-willy@xxxxxxxxxxxxx Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> Cc: Huang Ying <ying.huang@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/huge_memory.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/mm/huge_memory.c~mm-huge_memory-fix-can_split_huge_page-assumption-of-thp-size +++ a/mm/huge_memory.c @@ -2553,9 +2553,9 @@ bool can_split_huge_page(struct page *pa /* Additional pins from page cache */ if (PageAnon(page)) - extra_pins = PageSwapCache(page) ? HPAGE_PMD_NR : 0; + extra_pins = PageSwapCache(page) ? thp_nr_pages(page) : 0; else - extra_pins = HPAGE_PMD_NR; + extra_pins = thp_nr_pages(page); if (pextra_pins) *pextra_pins = extra_pins; return total_mapcount(page) == page_count(page) - extra_pins - 1; _ Patches currently in -mm which might be from willy@xxxxxxxxxxxxx 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