From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C11A43B9D84; Tue, 2 Jun 2026 22:24:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780439049; cv=none; b=VvCf80typqc8iJz91zcNtX9MLGQxAIRXa0tqC1VGzKapsxiq/YdzsTKEO21JtgZRo7WJ7lAWDr6O+8vTQlg2o2rN0v0eV5ktYWwSUtHn8hBNBPu3/h73qhyoQZs8juEiDCZjXQsItcACO3wArfwDv6FRIqOOLCG63zIZxZpnLyA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780439049; c=relaxed/simple; bh=N9AkCg0Z2UI/J+Y3LjcNpADBTFeEXJxl/qv/gjYq0NM=; h=Date:To:From:Subject:Message-Id; b=WnhiU/zexS5A7hdDjgTL6K8FxSGAUDH+cdkLzGt2AFcB8juy1meD8/gI8HCTXYZ6JAmq/Wcv84SaLT5AC+fAjfqzXTbmhGqFMmNaInxmw1VUCN5PUfEbeuwu6IG5KW4oQ4DM2ULRi4Gx34xtLnPXpRKpdfo/td0k02JX+HvTdnY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=paN7rtro; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="paN7rtro" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 95DA21F00899; Tue, 2 Jun 2026 22:24:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1780439047; bh=CMNgR1wdgfjQ3Y+74+RnZe2qYoCvtFP3kP4zEdcZ5/U=; h=Date:To:From:Subject; b=paN7rtro3YdxOVzRIA8LBkwiNmNS0nDc6eE2OrNOJqDTvWDjRaEY0wcE8se5kaQPX gRA80uOssCkdlBGvDjtYpKu7p5b8iaNEgwAhMUgesu/fVP1V3sMcuIxPFGyC2XLxwb FyAyJcsyHXbZbUPitciX4Ez9Tm1QN843J0oqk+NQ= Date: Tue, 02 Jun 2026 15:24:07 -0700 To: mm-commits@vger.kernel.org,viro@zeniv.linux.org.uk,stable@vger.kernel.org,peterx@redhat.com,jack@suse.cz,david@kernel.org,brauner@kernel.org,rppt@kernel.org,akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-stable] userfaultfd-ensure-mremap_userfaultfd_fail-releases-mmap_changing.patch removed from -mm tree Message-Id: <20260602222407.95DA21F00899@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The quilt patch titled Subject: userfaultfd: ensure mremap_userfaultfd_fail() releases mmap_changing has been removed from the -mm tree. Its filename was userfaultfd-ensure-mremap_userfaultfd_fail-releases-mmap_changing.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: "Mike Rapoport (Microsoft)" Subject: userfaultfd: ensure mremap_userfaultfd_fail() releases mmap_changing Date: Wed, 13 May 2026 11:14:16 +0300 Sashiko says: mremap_userfaultfd_prep() increments ctx->mmap_changing to stall concurrent operations, but mremap_userfaultfd_fail() does not decrement it before dropping the context reference. If an mremap operation fails, ctx->mmap_changing remains elevated. This will causes subsequent userfaultfd operations like a UFFDIO_COPY to fail with -EAGAIN. Decrement ctx->mmap_changing in mremap_userfaultfd_fail(). Link: https://sashiko.dev/#/patchset/20260430113512.115938-1-rppt@kernel.org Link: https://lore.kernel.org/20260513081416.495963-1-rppt@kernel.org Fixes: df2cc96e7701 ("userfaultfd: prevent non-cooperative events vs mcopy_atomic races") Signed-off-by: Mike Rapoport (Microsoft) Reviewed-by: David Hildenbrand (Arm) Cc: Al Viro Cc: Christian Brauner Cc: Jan Kara Cc: Peter Xu Cc: Signed-off-by: Andrew Morton --- fs/userfaultfd.c | 2 ++ 1 file changed, 2 insertions(+) --- a/fs/userfaultfd.c~userfaultfd-ensure-mremap_userfaultfd_fail-releases-mmap_changing +++ a/fs/userfaultfd.c @@ -786,6 +786,8 @@ void mremap_userfaultfd_fail(struct vm_u if (!ctx) return; + atomic_dec(&ctx->mmap_changing); + VM_WARN_ON_ONCE(atomic_read(&ctx->mmap_changing) < 0); userfaultfd_ctx_put(ctx); } _ Patches currently in -mm which might be from rppt@kernel.org are selftests-mm-hugetlb-read-hwpoison-add-sigbus-handler.patch selftests-mm-migration-dont-assume-huge-page-is-twomeg.patch selftests-mm-migration-make-nthreads-represent-number-of-working-threads.patch selftests-mm-migration-properly-cleanup-forked-processes.patch selftests-mm-run_vmtestssh-dont-gate-thp-and-ksm-tests-on-have_hugepages.patch selftests-mm-merge-map_hugetlb-into-hugepage-mmap.patch selftests-mm-rename-hugepage-tests-to-hugetlb.patch selftests-mm-hugetlb-shm-use-kselftest-framework.patch selftests-mm-hugetlb-vmemmap-use-kselftest-framework.patch selftests-mm-hugetlb-madvise-use-kselftest-framework.patch selftests-mm-hugetlb_madv_vs_map-use-kselftest-framework.patch selftests-mm-hugetlb-read-hwpoison-use-kselftest-framework.patch selftests-mm-khugepaged-group-tests-in-an-array.patch selftests-mm-khugepaged-use-ksefltest-framework.patch selftests-mm-khugepaged-use-ksefltest-framework-fix.patch selftests-mm-ksm_tests-use-kselftest-framework.patch selftests-mm-protection_keys-use-descriptive-test-names-in-the-output.patch selftests-mm-protection_keys-use-kselftest-framework.patch selftests-mm-uffd-common-use-kselftest-framework.patch selftests-mm-uffd-stress-use-kselftest-framework.patch selftests-mm-uffd-unit-tests-use-kselftest-framework.patch selftests-mm-va_high_addr_switch-use-kselftest-framework.patch selftests-mm-add-atexit-and-signal-handlers-to-thp_settings.patch selftests-mm-rename-thp_settings-to-hugepage_settings.patch selftests-mm-move-hugetlb-helpers-to-hugepage_settings.patch selftests-mm-hugepage_settings-use-unsigned-long-in-detect_hugetlb_page_size.patch selftests-mm-hugepage_settings-add-apis-to-get-and-set-nr_hugepages.patch selftests-mm-hugepage_settings-rename-and-rework-get_free_hugepages.patch selftests-mm-hugepage_settings-add-apis-for-hugetlb-setup-and-teardown.patch selftests-mm-move-read_file-read_num-and-write_num-to-vm_util.patch selftests-mm-vm_util-add-helpers-to-set-and-restore-shm-limits.patch selftests-mm-compaction_test-use-hugetlb-helpers.patch selftests-mm-cow-add-setup-of-hugetlb-pages.patch selftests-mm-gup_longterm-add-setup-of-hugetlb-pages.patch selftests-mm-gup_test-add-setup-of-hugetlb-pages.patch selftests-mm-hmm-tests-add-setup-of-hugetlb-pages.patch selftests-mm-hugepage_dio-add-setup-of-hugetlb-pages.patch selftests-mm-hugetlb_fault_after_madv-add-setup-of-hugetlb-pages.patch selftests-mm-hugetlb-madvise-add-setup-of-hugetlb-pages.patch selftests-mm-hugetlb_madv_vs_map-add-setup-of-hugetlb-pages.patch selftests-mm-hugetlb-mmap-add-setup-of-hugetlb-pages.patch selftests-mm-hugetlb-mremap-add-setup-of-hugetlb-pages.patch selftests-mm-hugetlb-shm-add-setup-of-hugetlb-pages.patch selftests-mm-hugetlb-soft-offline-add-setup-of-hugetlb-pages.patch selftests-mm-hugetlb-vmemmap-add-setup-of-hugetlb-pages.patch selftests-mm-migration-add-setup-of-hugetlb-pages.patch selftests-mm-pagemap_ioctl-add-setup-of-hugetlb-pages.patch selftests-mm-protection_keys-use-library-code-for-hugetlb-setup.patch selftests-mm-thuge-gen-add-setup-of-hugetlb-pages.patch selftests-mm-uffd-stress-use-hugetlb_save-and-alloc-huge-pages.patch selftests-mm-uffd-unit-tests-add-setup-of-hugetlb-pages.patch selftests-mm-uffd-wp-mremap-add-setup-of-hugetlb-pages.patch selftests-mm-va_high_addr_switch-add-setup-of-hugetlb-pages.patch selftests-mm-va_high_addr_switchsh-drop-huge-pages-setup.patch selftests-mm-run_vmtestssh-free-memory-if-available-memory-is-low.patch selftests-mm-run_vmtestssh-drop-detection-and-setup-of-hugetlb.patch xor-use-kmalloc-in-calibrate_xor_blocks.patch raid6-use-kmalloc-in-raid6_select_algo.patch