The patch titled Subject: mm: switch gup_hugepte to use try_get_compound_head has been added to the -mm tree. Its filename is mm-switch-gup_hugepte-to-use-try_get_compound_head.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-switch-gup_hugepte-to-use-try_get_compound_head.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-switch-gup_hugepte-to-use-try_get_compound_head.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: Christoph Hellwig <hch@xxxxxx> Subject: mm: switch gup_hugepte to use try_get_compound_head This applies the overflow fixes from 8fde12ca79aff ("mm: prevent get_user_pages() from overflowing page refcount") to the powerpc hugepd code and brings it back in sync with the other GUP cases. Link: http://lkml.kernel.org/r/20190625143715.1689-16-hch@xxxxxx Signed-off-by: Christoph Hellwig <hch@xxxxxx> Cc: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: David Miller <davem@xxxxxxxxxxxxx> Cc: James Hogan <jhogan@xxxxxxxxxx> Cc: Jason Gunthorpe <jgg@xxxxxxxxxxxx> Cc: Khalid Aziz <khalid.aziz@xxxxxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: Nicholas Piggin <npiggin@xxxxxxxxx> Cc: Paul Burton <paul.burton@xxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx> Cc: Rich Felker <dalias@xxxxxxxx> Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/gup.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/mm/gup.c~mm-switch-gup_hugepte-to-use-try_get_compound_head +++ a/mm/gup.c @@ -2006,7 +2006,8 @@ static int gup_hugepte(pte_t *ptep, unsi refs++; } while (addr += PAGE_SIZE, addr != end); - if (!page_cache_add_speculative(head, refs)) { + head = try_get_compound_head(head, refs); + if (!head) { *nr -= refs; return 0; } _ Patches currently in -mm which might be from hch@xxxxxx are mm-remove-the-account_page_dirtied-export.patch mm-fix-an-overly-long-line-in-read_cache_page.patch mm-dont-cast-readpage-to-filler_t-for-do_read_cache_page.patch jffs2-pass-the-correct-prototype-to-read_cache_page.patch 9p-pass-the-correct-prototype-to-read_cache_page.patch mm-use-untagged_addr-for-get_user_pages_fast-addresses.patch mm-simplify-gup_fast_permitted.patch mm-lift-the-x86_32-pae-version-of-gup_get_pte-to-common-code.patch mips-use-the-generic-get_user_pages_fast-code.patch sh-add-the-missing-pud_page-definition.patch sh-use-the-generic-get_user_pages_fast-code.patch sparc64-add-the-missing-pgd_page-definition.patch sparc64-define-untagged_addr.patch sparc64-use-the-generic-get_user_pages_fast-code.patch mm-rename-config_have_generic_gup-to-config_have_fast_gup.patch mm-reorder-code-blocks-in-gupc.patch mm-consolidate-the-get_user_pages-implementations.patch mm-validate-get_user_pages_fast-flags.patch mm-move-the-powerpc-hugepd-code-to-mm-gupc.patch mm-switch-gup_hugepte-to-use-try_get_compound_head.patch mm-mark-the-page-referenced-in-gup_hugepte.patch