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 C4228372071 for ; Sun, 27 Sep 2026 21:55:58 +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=1790546160; cv=none; b=hAUz07AOpnW4P84O1wd7AEpQTLhLODyeNAiiqGGIQ3fdwzqpa5T7wbe/4DXdLE8YMVruf290ro+WQshHiO88DXwKc7slwNGLaRmd58Oc0dgZ8WQHhRtpft1b2NJSV29P6v63AdLeB3keMKfmxafdQCmPX6uP+0e+Z4SMecnRx6s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790546160; c=relaxed/simple; bh=qQIYQvJNNjXqfjXHZ+K1v5kas57WErIscrf/ql8aO9U=; h=Date:To:From:Subject:Message-Id; b=bYidzOlFcb8hziApZdfjff+2Bix9QUnPdhd2hmd853bNfcY1u4BLerfVj8NTci4V6LlIlT6/afNrswkNf0c82z3JMp4+/T1mlDfMTROHaQ1TyRgu5DCOKB1NEUmc1efWfpMJreu/V3O7ZYRM54CI2//3IHE3SsRGuMCmRku0jxQ= 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=uwZOJlFK; 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="uwZOJlFK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9985E1F000FF; Sun, 27 Sep 2026 21:55:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1790546158; bh=cJmR5wyLwKcz5u1XgWfMR10TLxlGIo2kF7/7JAiRsVk=; h=Date:To:From:Subject; b=uwZOJlFKnmEwqoBfeXI/YD5twMQtS8gOpucYVlrHchG2LoC/J5ks0hVxaK8uWNBLM vOvx8vM5NMYNXscS8t1uvoki8RikCL2xJ+4BxaXGwhe4gLiyelTlDDw7QRGvxys7L6 6233sMdadsinmapUxE4z5UtUM8mQ431eRHn80UGI= Date: Sun, 27 Sep 2026 14:55:58 -0700 To: mm-commits@vger.kernel.org,ljs@kernel.org,akpm@linux-foundation.org From: Andrew Morton Subject: + tools-testing-vma-add-test-to-assert-map_private-dev-zero-is-anon.patch added to mm-unstable branch Message-Id: <20260927215558.9985E1F000FF@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: tools/testing/vma: add test to assert MAP_PRIVATE-/dev/zero is anon has been added to the -mm mm-unstable branch. Its filename is tools-testing-vma-add-test-to-assert-map_private-dev-zero-is-anon.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/tools-testing-vma-add-test-to-assert-map_private-dev-zero-is-anon.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm 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 via various branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there most days ------------------------------------------------------ From: "Lorenzo Stoakes (ARM)" Subject: tools/testing/vma: add test to assert MAP_PRIVATE-/dev/zero is anon Date: Tue, 08 Sep 2026 12:23:42 +0100 Now we've made MAP_PRIVATE-mapped /dev/zero mappings truly anonymous, add a VMA userland test to assert that this is the case and everything is as we would expect for an anonymous mapping. Link: https://lore.kernel.org/20260908-map-private-dev-zero-v2-5-acc7b5625305@kernel.org Acked-by: David Hildenbrand (Arm) Signed-off-by: Lorenzo Stoakes (ARM) Signed-off-by: Andrew Morton Cc: Arnd Bergmann Cc: Baolin Wang Cc: Greg Kroah-Hartman Cc: Hugh Dickins Cc: Jan Kara Cc: Jann Horn Cc: Liam R. Howlett Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Mike Rapoport (Microsoft) Cc: Pedro Falcato Cc: Suren Baghdasaryan Cc: Vlastimil Babka --- tools/testing/vma/tests/mmap.c | 37 +++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) --- a/tools/testing/vma/tests/mmap.c~tools-testing-vma-add-test-to-assert-map_private-dev-zero-is-anon +++ a/tools/testing/vma/tests/mmap.c @@ -45,7 +45,44 @@ static bool test_mmap_region_basic(void) return true; } +static bool test_pure_anon_dev_zero(void) +{ + const vma_flags_t vma_flags = mk_vma_flags(VMA_READ_BIT, VMA_WRITE_BIT, + VMA_MAYREAD_BIT, VMA_MAYWRITE_BIT); + struct file file = { + .f_op = &zero_fops, + }; + struct mm_struct mm = {}; + struct vm_area_struct *vma; + unsigned long addr; + VMA_ITERATOR(vmi, &mm, 0); + + current->mm = &mm; + + /* + * Map a MAP_PRIVATE-/dev/zero mapping at address 0x300000 with a page + * offset of 0x10, which we expect to be reset to the anonymous page + * offset. + */ + addr = __mmap_region(&file, 0x300000, 0x3000, vma_flags, 0x10, NULL); + ASSERT_EQ(addr, 0x300000); + + /* Assert that it truly is an anonymous mapping. */ + vma = vma_lookup(&mm, addr); + ASSERT_NE(vma, NULL); + ASSERT_TRUE(vma_is_anonymous(vma)); + ASSERT_EQ(vma->vm_file, NULL); + ASSERT_EQ(vma->vm_private_data, NULL); + /* Expect anonymous page offsets. */ + ASSERT_EQ(vma->vm_pgoff, 0x300); + ASSERT_EQ(vma_start_anon_pgoff(vma), 0x300); + + cleanup_mm(&mm, &vmi); + return true; +} + static void run_mmap_tests(int *num_tests, int *num_fail) { TEST(mmap_region_basic); + TEST(pure_anon_dev_zero); } _ Patches currently in -mm which might be from ljs@kernel.org are mm-mremap-fix-locked_vm-leak-from-mremap_dontunmap-self-merge.patch mm-mremap-fix-locked_vm-leak-by-splitting-vma-for-mremap_dontunmap.patch mm-vmpressure-remove-window-size-todo.patch tools-testing-selftests-mm-add-missing-gitignore-entries.patch mm-move-drivers-char-memc-to-mm-char-memc.patch mm-implement-file_is_dev_zero-to-uniquely-identify-dev-zero.patch mm-vma-only-permit-map_private-dev-zero-to-be-mapped-anonymous.patch mm-vma-make-map_private-mapped-dev-zero-mappings-truly-anonymous.patch tools-testing-vma-add-test-to-assert-map_private-dev-zero-is-anon.patch tools-testing-selftests-mm-add-map_private-dev-zero-merge-tests.patch mm-madvise-swap-in-cowd-map_private-file-mappings-on-madv_willneed.patch mm-khugepaged-deposit-a-newly-allocated-page-table-on-collapse.patch mm-enable-mmu_gather_rcu_table_free-for-most-2-level-architectures.patch mm-enable-mmu_gather_rcu_table_free-for-mmu-riscv.patch mm-enable-mmu_gather_rcu_table_free-for-mmu-arm.patch mm-enable-mmu_gather_rcu_table_free-for-arc-microblaze-xtensa.patch mm-enable-mmu_gather_rcu_table_free-for-sparc64.patch mm-enable-mmu_gather_rcu_table_free-for-m68k-coldfire.patch mm-enable-mmu_gather_rcu_table_free-for-sh-x2.patch mm-enable-mmu_gather_rcu_table_free-for-m68k-motorola.patch mm-enable-mmu_gather_rcu_table_free-for-sparc32.patch mm-userland-pgtable-freeing-is-rcu-safe-now-remove-leftover-bits.patch mm-change-the-contract-for-free_pgtables-update-docs.patch mm-vma-fix-mmap_prepare-file-handling-remove-file_doesnt_need_get.patch mm-vma-introduce-and-use-vma_can_merge.patch mm-consistently-validate-vma-state-after-mmap-hooks.patch mm-vma-ensure-mmap_prepare-doesnt-set-actions-on-a-mergeable-vma.patch mm-make-map_kernel_pages_-internal-and-unexported.patch mm-vma-tidy-up-map-kernel-pages-enum-values.patch mm-add-mmap-action-for-discontiguous-kernel-page-mapping.patch docs-filesystems-update-mmap_prepare-docs-for-discontig-kernel-pgs.patch drivers-usb-mon-update-to-use-mmap_prepare-map-kernel-pages.patch infiniband-update-hfi1-to-use-remap_vmalloc_range.patch selinux-reject-writable-opens-of-policy-file-drop-mmap-shared-write-check.patch alsa-pcm-use-vm_insert_page-to-map-pcm-status-page.patch bpf-arena-mark-arena_map_mmap-mappings-vm_mixedmap.patch mm-vma-add-vma_is_kernel_owned-predicates.patch mm-vma-only-allow-mmap-to-clear-vma_maywrite_bit-if-kernel-owned.patch mm-vma-add-and-use-vma__is_fixed_mapping.patch scsi-sg-convert-mmap-hook-to-mmap_prepare-and-rework.patch fbdev-defio-assert-fbinfo_virtfb-drop-vm_io-add-vm_mixedmap.patch hsi-cmt_speech-convert-mmap-hook-to-mmap_prepare-refactor.patch mm-gup-error-out-early-on-vma_mayread_bit-vmas.patch uprobes-remove-vm_io-set-vm_mixedmap-for-mapped-kernel-pages.patch mm-mlock-clear-vma_locked_mask-over-mmap-callback.patch mm-mlock-eliminate-weird-vma_io_bit-abuse-and-simplify.patch mm-vma-enforce-that-only-kernel-owned-mappings-may-set-vma_io_bit.patch mm-remove-vma_io_bit-check-in-vma_is_kernel_owned.patch mm-remove-hugetlb_inlineh.patch mm-rename-is_vm_hugetlb_page-to-vma_is_hugetlb.patch mm-drop-some-redundant-checks-around-hugetlb-vmas.patch mm-madvise-update-is_valid_guard_vma-to-use-vma_can_merge.patch mm-vma-introduce-vma_is_persistent.patch mm-uffd-use-predicates-for-userfaultfd-checks.patch mm-madvise-use-predicates-for-madvise-madv_dofork.patch mm-eliminate-vma_special_flags-usage-when-hugetlb-explicitly-tested.patch mm-eliminate-vma_special_flags-check-in-lru_gen_look_around.patch mm-avoid-use-of-vma_special_flags-in-migrate_vma_setup.patch mm-eliminate-vm_special-vma_special_flags.patch fuse-dax-do-not-set-vm_mixedmap.patch mm-huge_memory-remove-vma_is_special_huge.patch mm-vma-introduce-and-use-vma_can_gup.patch mm-vma-const-ify-vma_assert_stabilised-and-associated-functions.patch mm-implement-and-use-vma_has_anon_rmap-silence-kcsan.patch mm-update-comments-to-refer-to-anon-rmap-rather-than-anon_vma.patch mm-vma-dont-remove-vma-from-rmap-if-pgoff-unchanged.patch