From nobody Wed Oct 8 04:08:43 2025 Received: from sender4-pp-f112.zoho.com (sender4-pp-f112.zoho.com [136.143.188.112]) (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 734A128A725; Wed, 2 Jul 2025 14:21:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.188.112 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751466098; cv=pass; b=NANORY3Bq3GCB5StX7XVWU2iZVzBVmGVKZTn73mzS1Ta+ECQGc9PuAMYVMJEtEHsv4ij5jBU8h7HlI3iF7BrnG/2IChjqCwCANmb85PIwaNhaZjmHsebEe85Flqykjym5RvOksIW/JtNvjzpys5hR9hZGmOX8yT77PpRdtyD4L8= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751466098; c=relaxed/simple; bh=JPYsE1H9x9ALSEZAE4peMOPJnkOXnIORtP4J63kxwPs=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=H0o9NU7Afze0bLqQnoHX+6UI+t58qqehKW3hQyhr4zNGIOD5kUZpqEJMnPOvlbHUJeTovwFhg+iJTsCgtMjLVdHdf7N4t4uiaTImqOG5SZkpJY157/B4Bu4MwQgWZoZ9XPztkgj0HXyhXKnQB3asXKfoYMXxjAUySv76Elt3h34= ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (1024-bit key) header.d=collabora.com header.i=usama.anjum@collabora.com header.b=P0SRCvrM; arc=pass smtp.client-ip=136.143.188.112 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=collabora.com header.i=usama.anjum@collabora.com header.b="P0SRCvrM" ARC-Seal: i=1; a=rsa-sha256; t=1751466079; cv=none; d=zohomail.com; s=zohoarc; b=JjFU/wTd7C2n15LaDCtVw4c5SLp4fYQqW6KjugfaTRu/jrmZUzM7J1qZEA5663zmu2VMSmqqPWfgFHC/G5zg8zG00gmgYt6fuulxDF7929o8jETu/Yi1Y1WhP/56M8bYWX/A6c6xlLDQaLbQ/GpVVn668HTpb2DNsduuG1EyR9A= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1751466079; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:MIME-Version:Message-ID:Subject:Subject:To:To:Message-Id:Reply-To; bh=2/PLCRDX5zQwb9vO9glSCFCybgO+wL+GFj+YcKmCwxY=; b=jw62NL3OcEjtChqVcuhIwONQ4/RJoR3PkVG8VXFYPHRdI2zHk7NE5BiXDxudPZlf9ucTTYJ6ChV2EMnmPiWjvGEBnsk8tWIitCoqvTdS7ILlteRDTqzOIk+qvzEttwVisP2xi5FXTESHTDmXiUSxjZH2Skx2GjewoYJ5IFMNq1A= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=collabora.com; spf=pass smtp.mailfrom=usama.anjum@collabora.com; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1751466079; s=zohomail; d=collabora.com; i=usama.anjum@collabora.com; h=From:From:To:To:Cc:Cc:Subject:Subject:Date:Date:Message-ID:MIME-Version:Content-Transfer-Encoding:Message-Id:Reply-To; bh=2/PLCRDX5zQwb9vO9glSCFCybgO+wL+GFj+YcKmCwxY=; b=P0SRCvrMW8to+PMLKnzJMzI7zPfWcLYGtY2c80g3CSvPjZlBCZhPbCSkNPTbRjks i2g+VeY3blhZx3RiCgPNMNULw9hjGdTTPkEm56Mv9Z5Ap0J3UgXkVI5UFi9q0qJCTgi hlgvEaL4lqwXkNTwF/A02GAlIYAoMJiFO6XeP+Q8= Received: by mx.zohomail.com with SMTPS id 1751466077488209.397213001875; Wed, 2 Jul 2025 07:21:17 -0700 (PDT) From: Muhammad Usama Anjum To: Andrew Morton , Shuah Khan Cc: Muhammad Usama Anjum , kernel@collabora.com, David Hildenbrand , linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2] selftests/mm: pagemap_scan ioctl: add PFN ZERO test cases Date: Wed, 2 Jul 2025 19:20:51 +0500 Message-ID: <20250702142052.45116-1-usama.anjum@collabora.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ZohoMailClient: External Content-Type: text/plain; charset="utf-8" Add test cases to test the correctness of PFN ZERO flag of pagemap_scan ioctl. Test with normal pages backed memory and huge pages backed memory. Cc: David Hildenbrand Signed-off-by: Muhammad Usama Anjum --- The bug has been fixed [1]. [1] https://lore.kernel.org/all/20250617143532.2375383-1-david@redhat.com Changes since v1: - Skip if madvise() fails - Skip test if use_zero_page isn't set to 1 - Keep on using memalign()+free() to allocate huge pages --- tools/testing/selftests/mm/pagemap_ioctl.c | 86 +++++++++++++++++++++- 1 file changed, 85 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/mm/pagemap_ioctl.c b/tools/testing/sel= ftests/mm/pagemap_ioctl.c index 57b4bba2b45f3..976ab357f4651 100644 --- a/tools/testing/selftests/mm/pagemap_ioctl.c +++ b/tools/testing/selftests/mm/pagemap_ioctl.c @@ -1,4 +1,5 @@ // SPDX-License-Identifier: GPL-2.0 + #define _GNU_SOURCE #include #include @@ -1480,6 +1481,86 @@ static void transact_test(int page_size) extra_thread_faults); } =20 +bool is_use_zero_page_set(void) +{ + ssize_t bytes_read; + char buffer[2]; + int fd; + + fd =3D open("/sys/kernel/mm/transparent_hugepage/use_zero_page", O_RDONLY= ); + if (fd < 0) + return 0; + + bytes_read =3D read(fd, buffer, sizeof(buffer) - 1); + if (bytes_read <=3D 0) { + close(fd); + return 0; + } + + close(fd); + if (atoi(buffer) !=3D 1) + return 0; + + return 1; +} + +void zeropfn_tests(void) +{ + unsigned long long mem_size; + struct page_region vec; + int i, ret; + char *mem; + + /* Test with normal memory */ + mem_size =3D 10 * page_size; + mem =3D mmap(NULL, mem_size, PROT_READ, MAP_PRIVATE | MAP_ANON, -1, 0); + if (mem =3D=3D MAP_FAILED) + ksft_exit_fail_msg("error nomem\n"); + + /* Touch each page to ensure it's mapped */ + for (i =3D 0; i < mem_size; i +=3D page_size) + (void)((volatile char *)mem)[i]; + + ret =3D pagemap_ioctl(mem, mem_size, &vec, 1, 0, + (mem_size / page_size), PAGE_IS_PFNZERO, 0, 0, PAGE_IS_PFNZERO); + if (ret < 0) + ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno)); + + ksft_test_result(ret =3D=3D 1 && LEN(vec) =3D=3D (mem_size / page_size), + "%s all pages must have PFNZERO set\n", __func__); + + munmap(mem, mem_size); + + /* Test with huge page if user_zero_page is set to 1 */ + if (!is_use_zero_page_set()) { + ksft_test_result_skip("%s use_zero_page not supported or set to 1\n", __= func__); + return; + } + + mem_size =3D 10 * hpage_size; + mem =3D memalign(hpage_size, mem_size); + if (!mem) + ksft_exit_fail_msg("error nomem\n"); + + ret =3D madvise(mem, mem_size, MADV_HUGEPAGE); + if (!ret) { + for (i =3D 0; i < mem_size; i +=3D hpage_size) + (void)((volatile char *)mem)[i]; + + ret =3D pagemap_ioctl(mem, mem_size, &vec, 1, 0, + (mem_size / page_size), PAGE_IS_PFNZERO, 0, 0, PAGE_IS_PFNZERO); + if (ret < 0) + ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno)); + + ksft_test_result(ret =3D=3D 1 && LEN(vec) =3D=3D (mem_size / page_size), + "%s all huge pages must have PFNZERO set\n", __func__); + + free(mem); + } else { + ksft_test_result_skip("%s huge page not supported\n", __func__); + } +} + int main(int __attribute__((unused)) argc, char *argv[]) { int shmid, buf_size, fd, i, ret; @@ -1494,7 +1575,7 @@ int main(int __attribute__((unused)) argc, char *argv= []) if (init_uffd()) ksft_exit_pass(); =20 - ksft_set_plan(115); + ksft_set_plan(117); =20 page_size =3D getpagesize(); hpage_size =3D read_pmd_pagesize(); @@ -1669,6 +1750,9 @@ int main(int __attribute__((unused)) argc, char *argv= []) /* 16. Userfaultfd tests */ userfaultfd_tests(); =20 + /* 17. ZEROPFN tests */ + zeropfn_tests(); + close(pagemap_fd); ksft_exit_pass(); } --=20 2.43.0