+ mm-support-gup-triggered-unsharing-of-anonymous-pages-fix.patch added to -mm tree

+ mm-support-gup-triggered-unsharing-of-anonymous-pages-fix.patch added to -mm tree

[Andrew Morton]

The patch titled
     Subject: mm-support-gup-triggered-unsharing-of-anonymous-pages-fix
has been added to the -mm tree.  Its filename is
     mm-support-gup-triggered-unsharing-of-anonymous-pages-fix.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-support-gup-triggered-unsharing-of-anonymous-pages-fix.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-support-gup-triggered-unsharing-of-anonymous-pages-fix.patch

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------------------------------------------------------
From: David Hildenbrand <david@redhat.com>
Subject: mm-support-gup-triggered-unsharing-of-anonymous-pages-fix

Link: https://lkml.kernel.org/r/c003964a-9fa1-b17c-158a-8ccbf4ff8656@redhat.com
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memory.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/mm/memory.c~mm-support-gup-triggered-unsharing-of-anonymous-pages-fix
+++ a/mm/memory.c
@@ -3132,7 +3132,7 @@ static vm_fault_t wp_page_copy(struct vm
 			free_swap_cache(old_page);
 		put_page(old_page);
 	}
-	return page_copied && !unshare ? VM_FAULT_WRITE : 0;
+	return (page_copied && !unshare) ? VM_FAULT_WRITE : 0;
 oom_free_new:
 	put_page(new_page);
 oom:
@@ -4557,7 +4557,7 @@ static inline vm_fault_t wp_huge_pmd(str
 	const bool unshare = vmf->flags & FAULT_FLAG_UNSHARE;
 
 	if (vma_is_anonymous(vmf->vma)) {
-		if (unlikely(unshare) &&
+		if (likely(!unshare) &&
 		    userfaultfd_huge_pmd_wp(vmf->vma, vmf->orig_pmd))
 			return handle_userfault(vmf, VM_UFFD_WP);
 		return do_huge_pmd_wp_page(vmf);
_

Patches currently in -mm which might be from david@redhat.com are

mm-rmap-fix-missing-swap_free-in-try_to_unmap-after-arch_unmap_one-failed.patch
mm-hugetlb-take-src_mm-write_protect_seq-in-copy_hugetlb_page_range.patch
mm-memory-slightly-simplify-copy_present_pte.patch
mm-rmap-split-page_dup_rmap-into-page_dup_file_rmap-and-page_try_dup_anon_rmap.patch
mm-rmap-convert-rmap-flags-to-a-proper-distinct-rmap_t-type.patch
mm-rmap-remove-do_page_add_anon_rmap.patch
mm-rmap-pass-rmap-flags-to-hugepage_add_anon_rmap.patch
mm-rmap-drop-compound-parameter-from-page_add_new_anon_rmap.patch
mm-rmap-use-page_move_anon_rmap-when-reusing-a-mapped-pageanon-page-exclusively.patch
mm-huge_memory-remove-outdated-vm_warn_on_once_page-from-unmap_page.patch
mm-page-flags-reuse-pg_mappedtodisk-as-pg_anon_exclusive-for-pageanon-pages.patch
mm-remember-exclusively-mapped-anonymous-pages-with-pg_anon_exclusive.patch
mm-gup-disallow-follow_pagefoll_pin.patch
mm-support-gup-triggered-unsharing-of-anonymous-pages.patch
mm-support-gup-triggered-unsharing-of-anonymous-pages-fix.patch
mm-gup-trigger-fault_flag_unshare-when-r-o-pinning-a-possibly-shared-anonymous-page.patch
mm-gup-sanity-check-with-config_debug_vm-that-anonymous-pages-are-exclusive-when-unpinning.patch
mm-swap-remember-pg_anon_exclusive-via-a-swp-pte-bit.patch
mm-swap-remember-pg_anon_exclusive-via-a-swp-pte-bit-fix.patch
mm-debug_vm_pgtable-add-tests-for-__have_arch_pte_swp_exclusive.patch
x86-pgtable-support-__have_arch_pte_swp_exclusive.patch
arm64-pgtable-support-__have_arch_pte_swp_exclusive.patch
s390-pgtable-cleanup-description-of-swp-pte-layout.patch
s390-pgtable-support-__have_arch_pte_swp_exclusive.patch
powerpc-pgtable-remove-_page_bit_swap_type-for-book3s.patch
powerpc-pgtable-support-__have_arch_pte_swp_exclusive-for-book3s.patch