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 178FC4FC8F4 for ; Tue, 8 Sep 2026 23:46:33 +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=1788911194; cv=none; b=Sz2bfKdN7ecLrkgoZraEK5IcAtqLX8O0oMpxWVjPyoKfj6aqTmRtto5kW8/URlTAIiKUjZ/HAuh4qOiBFydj+g5rlerMprBkB3Q1rkPAWrTDahCTKv4inWkOAPoarDh2CNz+hFu8+yVXtaW3DHMAXUzBytksBgNZlQLiqqzOES8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788911194; c=relaxed/simple; bh=dzeG/L1TcJV2bf/jm+fBta7CHtdY30vbQdsdLmaudyw=; h=Date:To:From:Subject:Message-Id; b=tgcA8r3dsrqPShC8eAuzA/jEsuzlicQDMW/S6iwaBATgGBqzbgCueJlXlpCLJStKHowawP2BPbaX0x73XCfD2iEaVELR1iQWWVT1GEBlI3U8GcOgsOqdq384hZ/1K6S7QEXcFeZZdOrYsh8TKQQt/PwqKHwjTfW4Qn/KZ2KpSMo= 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=xmsF+FLY; 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="xmsF+FLY" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BF9671F00A3A; Tue, 8 Sep 2026 23:46:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1788911192; bh=ccDhQ6SKx6Tul/Z4USzplW6dUbX6YjY90LSSyw6897I=; h=Date:To:From:Subject; b=xmsF+FLYTpfDW2yZRkdtk+VJ1vxHLbHxd2EjPyp7KT4JYVecjkGz0y8a2smodefIt 3vz8Zpy0IWr5ET4YlheeBLt3q0ZS8vCyXPNLW3813tmyQE4Dwz5k1psqecwBqxlkCY MScHaQdEvVRT8r531V4xAyy40tVnQ52j9F1MqN7c= Date: Tue, 08 Sep 2026 16:46:32 -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: <20260908234632.BF9671F00A3A@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) 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 Signed-off-by: Andrew Morton --- 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-vma-correctly-unaccount-on-mmap_prepare-failure.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-huge_memory-zap-deposited-page-tables-after-an-rcu-grace-period.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-make-userland-page-table-freeing-rcu-safe.patch mm-change-the-contract-for-free_pgtables-update-docs.patch