The patch titled Subject: mm-hugetlb-fix-uffd-wr-protection-for-cow-optimization-path-v3 has been added to the -mm mm-hotfixes-unstable branch. Its filename is mm-hugetlb-fix-uffd-wr-protection-for-cow-optimization-path-v3.patch

This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...

This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------ From: Peter Xu peterx@redhat.com Subject: mm-hugetlb-fix-uffd-wr-protection-for-cow-optimization-path-v3 Date: Fri, 24 Mar 2023 10:26:20 -0400

Link: https://lkml.kernel.org/r/20230324142620.2344140-1-peterx@redhat.com Reported-by: Muhammad Usama Anjum usama.anjum@collabora.com Cc: linux-stable stable@vger.kernel.org Fixes: 166f3ecc0daf ("mm/hugetlb: hook page faults for uffd write protection") Signed-off-by: Peter Xu peterx@redhat.com Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

mm/hugetlb.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)

--- a/mm/hugetlb.c~mm-hugetlb-fix-uffd-wr-protection-for-cow-optimization-path-v3 +++ a/mm/hugetlb.c @@ -5491,11 +5491,11 @@ static vm_fault_t hugetlb_wp(struct mm_s * Never handle CoW for uffd-wp protected pages. It should be only * handled when the uffd-wp protection is removed. * - * Note that only the CoW optimization path can trigger this and - * got skipped, because hugetlb_fault() will always resolve uffd-wp - * bit first. + * Note that only the CoW optimization path (in hugetlb_no_page()) + * can trigger this, because hugetlb_fault() will always resolve + * uffd-wp bit first. */ - if (huge_pte_uffd_wp(pte)) + if (!unshare && huge_pte_uffd_wp(pte)) return 0;

/* _

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

mm-hugetlb-fix-uffd-wr-protection-for-cow-optimization-path.patch mm-hugetlb-fix-uffd-wr-protection-for-cow-optimization-path-v2.patch mm-hugetlb-fix-uffd-wr-protection-for-cow-optimization-path-v3.patch mm-khugepaged-alloc_charge_hpage-take-care-of-mem-charge-errors.patch mm-khugepaged-cleanup-memcg-uncharge-for-failure-path.patch mm-uffd-uffd_feature_wp_unpopulated.patch mm-uffd-uffd_feature_wp_unpopulated-fix.patch selftests-mm-smoke-test-uffd_feature_wp_unpopulated.patch mm-thp-rename-transparent_hugepage_never_dax-to-_unsupported.patch mm-thp-rename-transparent_hugepage_never_dax-to-_unsupported-fix.patch