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 D82F1346E56 for ; Thu, 25 Jun 2026 21:02:22 +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=1782421344; cv=none; b=nMDMZG1Pd3yHJGFFLosI6eh/8JG5Op1Qty1QwXdo27ZRuH4mdRG1wDRFCrjC73k6bsHTT3JHRkVHeZ/Kz9aU4LQnMxU1zV+ksOrd3QbVk3ZmVxOTZZ7n8oIubTOULvWkD1/QvI49u0LyKbaSVF2Eos3E7Subau797l8EltHEcps= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782421344; c=relaxed/simple; bh=+tylqv0Pl/2B/YrqcvMddEwcaWUvHBY0q3O3GGwO2ok=; h=Date:To:From:Subject:Message-Id; b=Cp2cuwMooPlEs+h5K0UpoKFs2HN/ceVZH2jiLkm5kIWrapF8CVri+969pLbC81+Al1BKoKHQWB1orb79aFUKegc4ga/u3UXsii0hYiMDlIGQsBC84aBHw1SxJYemv2jgyn6tTqn9lDf2eQ7bUBzA2UZh9ZUuNkHq2UjbUaLrOAE= 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=K7oaAPMC; 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="K7oaAPMC" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5F9DA1F000E9; Thu, 25 Jun 2026 21:02:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1782421342; bh=/O0zDj6qbcxmvYvbOsM4JlWrNsX47oU9gPhJ8PCfjPc=; h=Date:To:From:Subject; b=K7oaAPMCcypgLWhSYC12N9vkp0e6dBCK7+9rBRVJ5JItqu4KA+vdO3wR8e6/zQ3C8 K8JAD2tqFbQYzHM6zi3MoeJaeYyMM5pjmu6BUfDGBf5KRO60DIPrLCVCfEdjpW1jyo 7MGXX6C3pPKT//BmBIcuxgkk9GVNTAOTTXV8BOe0= Date: Thu, 25 Jun 2026 14:02:21 -0700 To: mm-commits@vger.kernel.org,ziy@nvidia.com,shuah@kernel.org,ritesh.list@gmail.com,osalvador@suse.de,mhocko@kernel.org,linmiaohe@huawei.com,liam.howlett@oracle.com,dev.jain@arm.com,david@kernel.org,sayalip@linux.ibm.com,akpm@linux-foundation.org From: Andrew Morton Subject: + selftests-mm-fix-ksm-numa-merge-test-for-systems-with-memoryless-numa-nodes.patch added to mm-new branch Message-Id: <20260625210222.5F9DA1F000E9@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The patch titled Subject: selftests/mm: fix ksm NUMA merge test for systems with memoryless NUMA nodes has been added to the -mm mm-new branch. Its filename is selftests-mm-fix-ksm-numa-merge-test-for-systems-with-memoryless-numa-nodes.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/selftests-mm-fix-ksm-numa-merge-test-for-systems-with-memoryless-numa-nodes.patch This patch will later appear in the mm-new branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Note, mm-new is a provisional staging ground for work-in-progress patches, and acceptance into mm-new is a notification for others take notice and to finish up reviews. Please do not hesitate to respond to review feedback and post updated versions to replace or incrementally fixup patches in mm-new. The mm-new branch of mm.git is not included in linux-next If a few days of testing in mm-new is successful, the patch will me moved into mm.git's mm-unstable branch, which is included in linux-next 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: Sayali Patil Subject: selftests/mm: fix ksm NUMA merge test for systems with memoryless NUMA nodes Date: Thu, 25 Jun 2026 18:10:17 +0530 The KSM NUMA merge test allocates identical pages on different NUMA nodes and verifies KSM behavior with merge_across_nodes enabled and disabled. On systems with memoryless NUMA nodes, for example: #numactl -H available: 2 nodes (0,4) ..... node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 node 0 size: 14825 MB node 0 free: 1382 MB node 4 cpus: node 4 size: 0 MB node 4 free: 0 MB the test may attempt to allocate memory on a node without memory, causing numa_alloc_onnode() to fail and resulting in a spurious test failure. Add count_mem_nodes() helper to count only nodes with memory and use it instead of numa_num_configured_nodes() to ensure the test runs only on systems with at least two NUMA nodes that have memory. Skip the test otherwise. Before patch: --------------------------- running ./ksm_tests -N -m 1 --------------------------- mbind: Invalid argument ok 1 KSM NUMA merging Totals: pass:1 fail:0 xfail:0 xpass:0 skip:0 error:0 [PASS] ok 1 ksm_tests -N -m 1 --------------------------- running ./ksm_tests -N -m 0 --------------------------- mbind: Invalid argument not ok 1 KSM NUMA merging Totals: pass:0 fail:1 xfail:0 xpass:0 skip:0 error:0 [FAIL] not ok 2 ksm_tests -N -m 0 # exit=1 After patch: --------------------------- running ./ksm_tests -N -m 1 --------------------------- SKIP At least 2 NUMA nodes with memory must be available Totals: pass:0 fail:0 xfail:0 xpass:0 skip:1 error:0 [SKIP] ok 1 ksm_tests -N -m 1 # SKIP --------------------------- running ./ksm_tests -N -m 0 --------------------------- SKIP At least 2 NUMA nodes with memory must be available Totals: pass:0 fail:0 xfail:0 xpass:0 skip:1 error:0 [SKIP] ok 2 ksm_tests -N -m 0 # SKIP Link: https://lore.kernel.org/8540b58ef1fdbc2e5cb2f9fe28a2d2a54a5bc6a8.1782365671.git.sayalip@linux.ibm.com Fixes: e3820ab252dd ("selftest/vm: fix ksm selftest to run with different NUMA topologies") Signed-off-by: Sayali Patil Cc: David Hildenbrand Cc: Dev Jain Cc: Liam Howlett Cc: Miaohe Lin Cc: Michal Hocko Cc: Oscar Salvador Cc: "Ritesh Harjani (IBM)" Cc: Shuah Khan Cc: Zi Yan Signed-off-by: Andrew Morton --- tools/testing/selftests/mm/ksm_tests.c | 26 +++++++++++++++-------- 1 file changed, 18 insertions(+), 8 deletions(-) --- a/tools/testing/selftests/mm/ksm_tests.c~selftests-mm-fix-ksm-numa-merge-test-for-systems-with-memoryless-numa-nodes +++ a/tools/testing/selftests/mm/ksm_tests.c @@ -450,6 +450,18 @@ static int get_first_mem_node(void) return get_next_mem_node(numa_max_node()); } +static int count_mem_nodes(void) +{ + int node, count = 0; + + for (node = 0; node <= numa_max_node(); node++) { + if (numa_node_size(node, NULL) > 0) + count++; + } + + return count; +} + static int check_ksm_numa_merge(int merge_type, int mapping, int prot, int timeout, bool merge_across_nodes, size_t page_size) { @@ -463,14 +475,12 @@ static int check_ksm_numa_merge(int merg return KSFT_FAIL; } - if (numa_available() < 0) { - ksft_print_msg("NUMA support not enabled\n"); - return KSFT_SKIP; - } - if (numa_num_configured_nodes() <= 1) { - ksft_print_msg("At least 2 NUMA nodes must be available\n"); - return KSFT_SKIP; - } + if (numa_available() < 0) + ksft_exit_skip("NUMA support not enabled\n"); + + if (count_mem_nodes() <= 1) + ksft_exit_skip("At least 2 NUMA nodes with memory must be available\n"); + if (ksm_write_sysfs(KSM_FP("merge_across_nodes"), merge_across_nodes)) return KSFT_FAIL; _ Patches currently in -mm which might be from sayalip@linux.ibm.com are selftests-mm-handle-einval-when-configuring-gigantic-hugepages.patch selftests-mm-fix-ksm-numa-merge-test-for-systems-with-memoryless-numa-nodes.patch