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 A815247CA67; Sat, 12 Sep 2026 12:46:58 +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=1789217220; cv=none; b=divTYb/OE9FFFNGOMbVo/ssq1sfwWcqLDyY/Kmks89uSyX1oi46KtTmIGdG3zavUfn9gy53Y3P14IcseAn3pva/jI8uyXSce0bceLF774VjLHTX5YhxhEp3sS8BJLvoA8SpgzJgGEn8pPeeRpKY1d/KZsxckAEq909j2qkBq4uE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789217220; c=relaxed/simple; bh=1oH5eSftYUCJmEQwOYyX9dRpHL49/fsyQvXx3b60+W8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=pRqtJL/70ZokGRJhdccrjbNzFfi+fi3FgJ7UhcV7TmjzVuvpoksyYCuaO9QEVvgw5MfIjE32AET4+HqUDQh8JBz6YEhlpM2+SGkOPV1tA3qgxWF3ypsUjuLEIb1DznJVk8fDxasvXXqc2w4rBfC0o3Bb8IcSVCyJLtc/lvXrogk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=11t2SH8g; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="11t2SH8g" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4D84D1F000FF; Sat, 12 Sep 2026 12:46:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789217218; bh=9LPW4KpI+FzdH3m1UxxLzTEIMGgSF2aFQiJNPuBRQgQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=11t2SH8gf3yJh5t2A+ywjdy0sv73kpIVSpxvXlsoEJVonkEAFfp3qsRrPxj7pZfPf cjT5zSMucokT4kiIPnIkZCDnUgPbktQ9HnTCX5/ZfwPijPxtXRIxCD0o8iRYVpJ5vN IqXbWT64AlHuMoZLtd1alDXRDu0PYBHF/GoOR/7s= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Li Wang , Aruna Ramakrishna , Bagas Sanjaya , Catalin Marinas , Dave Hansen , David Hildenbrand , Joey Gouly , Johannes Weiner , Keith Lucas , Ryan Roberts , Shuah Khan , Lorenzo Stoakes , Andrew Morton , Sasha Levin Subject: [PATCH 6.12 0897/1376] ksm_tests: skip hugepage test when Transparent Hugepages are disabled Date: Sat, 12 Sep 2026 08:55:23 +0200 Message-ID: <20260912065627.555309098@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065607.535295758@linuxfoundation.org> References: <20260912065607.535295758@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Li Wang [ Upstream commit fdc3bc3497946c6b416a17628907581657102e60 ] Some systems (e.g. minimal or real-time kernels) may not enable Transparent Hugepages (THP), causing MADV_HUGEPAGE to return EINVAL. This patch introduces a runtime check using the existing THP sysfs interface and skips the hugepage merging test (`-H`) when THP is not available. To avoid those failures: # ----------------------------- # running ./ksm_tests -H -s 100 # ----------------------------- # ksm_tests: MADV_HUGEPAGE: Invalid argument # [FAIL] not ok 1 ksm_tests -H -s 100 # exit=2 # -------------------- # running ./khugepaged # -------------------- # Reading PMD pagesize failed# [FAIL] not ok 1 khugepaged # exit=1 # -------------------- # running ./soft-dirty # -------------------- # TAP version 13 # 1..15 # ok 1 Test test_simple # ok 2 Test test_vma_reuse dirty bit of allocated page # ok 3 Test test_vma_reuse dirty bit of reused address page # Bail out! Reading PMD pagesize failed# Planned tests != run tests (15 != 3) # # Totals: pass:3 fail:0 xfail:0 xpass:0 skip:0 error:0 # [FAIL] not ok 1 soft-dirty # exit=1 # SUMMARY: PASS=0 SKIP=0 FAIL=1 # ------------------- # running ./migration # ------------------- # TAP version 13 # 1..3 # # Starting 3 tests from 1 test cases. # # RUN migration.private_anon ... # # OK migration.private_anon # ok 1 migration.private_anon # # RUN migration.shared_anon ... # # OK migration.shared_anon # ok 2 migration.shared_anon # # RUN migration.private_anon_thp ... # # migration.c:196:private_anon_thp:Expected madvise(ptr, TWOMEG, MADV_HUGEPAGE) (-1) == 0 (0) # # private_anon_thp: Test terminated by assertion # # FAIL migration.private_anon_thp # not ok 3 migration.private_anon_thp # # FAILED: 2 / 3 tests passed. # # Totals: pass:2 fail:1 xfail:0 xpass:0 skip:0 error:0 # [FAIL] not ok 1 migration # exit=1 It's true that CONFIG_TRANSPARENT_HUGEPAGE=y is explicitly enabled in tools/testing/selftests/mm/config, so ideally the runtime environment should also support THP. However, in practice, we've found that on some systems: - THP is disabled at boot time (transparent_hugepage=never) - Or manually disabled via sysfs - Or unavailable in RT kernels, containers, or minimal CI environments In these cases, the test will fail with EINVAL on madvise(MADV_HUGEPAGE), even though the kernel config is correct. To make the test suite more robust and avoid false negatives, this patch adds a runtime check for /sys/kernel/mm/transparent_hugepage/enabled. If THP is not available, the hugepage test (-H) is skipped with a clear message. Link: https://lkml.kernel.org/r/20250624032748.393836-1-liwang@redhat.com Signed-off-by: Li Wang Cc: Aruna Ramakrishna Cc: Bagas Sanjaya Cc: Catalin Marinas Cc: Dave Hansen Cc: David Hildenbrand Cc: Joey Gouly Cc: Johannes Weiner Cc: Keith Lucas Cc: Ryan Roberts Cc: Shuah Khan Cc: Lorenzo Stoakes Signed-off-by: Andrew Morton Stable-dep-of: 15828a150c58 ("selftests/mm: fix ksm NUMA merge test for systems with memoryless NUMA nodes") Signed-off-by: Sasha Levin --- tools/testing/selftests/mm/khugepaged.c | 5 +++++ tools/testing/selftests/mm/ksm_tests.c | 6 ++++++ tools/testing/selftests/mm/migration.c | 8 ++++++++ tools/testing/selftests/mm/soft-dirty.c | 9 ++++++++- tools/testing/selftests/mm/thp_settings.c | 11 +++++++++++ tools/testing/selftests/mm/thp_settings.h | 2 ++ 6 files changed, 40 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/mm/khugepaged.c b/tools/testing/selftests/mm/khugepaged.c index 8a4d34cce36b2..6822eb7ea58e8 100644 --- a/tools/testing/selftests/mm/khugepaged.c +++ b/tools/testing/selftests/mm/khugepaged.c @@ -1190,6 +1190,11 @@ int main(int argc, char **argv) .read_ahead_kb = 0, }; + if (!thp_is_enabled()) { + printf("Transparent Hugepages not available\n"); + return KSFT_SKIP; + } + parse_test_type(argc, argv); setbuf(stdout, NULL); diff --git a/tools/testing/selftests/mm/ksm_tests.c b/tools/testing/selftests/mm/ksm_tests.c index b748c48908d9d..faa3d053994df 100644 --- a/tools/testing/selftests/mm/ksm_tests.c +++ b/tools/testing/selftests/mm/ksm_tests.c @@ -15,6 +15,7 @@ #include "../kselftest.h" #include #include "vm_util.h" +#include "thp_settings.h" #define KSM_SYSFS_PATH "/sys/kernel/mm/ksm/" #define KSM_FP(s) (KSM_SYSFS_PATH s) @@ -555,6 +556,11 @@ static int ksm_merge_hugepages_time(int merge_type, int mapping, int prot, unsigned long scan_time_ns; int pagemap_fd, n_normal_pages, n_huge_pages; + if (!thp_is_enabled()) { + printf("Transparent Hugepages not available\n"); + return KSFT_SKIP; + } + map_size *= MB; size_t len = map_size; diff --git a/tools/testing/selftests/mm/migration.c b/tools/testing/selftests/mm/migration.c index cfd01e951e89c..7ad742c8c1325 100644 --- a/tools/testing/selftests/mm/migration.c +++ b/tools/testing/selftests/mm/migration.c @@ -5,6 +5,8 @@ */ #include "../kselftest_harness.h" +#include "thp_settings.h" + #include #include #include @@ -186,6 +188,9 @@ TEST_F_TIMEOUT(migration, private_anon_thp, 2*RUNTIME) uint64_t *ptr; int i; + if (!thp_is_enabled()) + SKIP(return, "Transparent Hugepages not available"); + if (self->nthreads < 2 || self->n1 < 0 || self->n2 < 0) SKIP(return, "Not enough threads or NUMA nodes available"); @@ -215,6 +220,9 @@ TEST_F_TIMEOUT(migration, shared_anon_thp, 2*RUNTIME) uint64_t *ptr; int i; + if (!thp_is_enabled()) + SKIP(return, "Transparent Hugepages not available"); + if (self->nthreads < 2 || self->n1 < 0 || self->n2 < 0) SKIP(return, "Not enough threads or NUMA nodes available"); diff --git a/tools/testing/selftests/mm/soft-dirty.c b/tools/testing/selftests/mm/soft-dirty.c index 7b91df12ce5b9..ca65ff3096b25 100644 --- a/tools/testing/selftests/mm/soft-dirty.c +++ b/tools/testing/selftests/mm/soft-dirty.c @@ -6,8 +6,10 @@ #include #include #include + #include "../kselftest.h" #include "vm_util.h" +#include "thp_settings.h" #define PAGEMAP_FILE_PATH "/proc/self/pagemap" #define TEST_ITERATIONS 10000 @@ -78,8 +80,13 @@ static void test_hugepage(int pagemap_fd, int pagesize) { char *map; int i, ret; - size_t hpage_len = read_pmd_pagesize(); + if (!thp_is_enabled()) { + ksft_test_result_skip("Transparent Hugepages not available\n"); + return; + } + + size_t hpage_len = read_pmd_pagesize(); if (!hpage_len) ksft_exit_fail_msg("Reading PMD pagesize failed"); diff --git a/tools/testing/selftests/mm/thp_settings.c b/tools/testing/selftests/mm/thp_settings.c index 577eaab6266fd..38f70155bfbf1 100644 --- a/tools/testing/selftests/mm/thp_settings.c +++ b/tools/testing/selftests/mm/thp_settings.c @@ -381,3 +381,14 @@ unsigned long thp_shmem_supported_orders(void) { return __thp_supported_orders(true); } + +bool thp_is_enabled(void) +{ + if (access(THP_SYSFS, F_OK) != 0) + return false; + + int mode = thp_read_string("enabled", thp_enabled_strings); + + /* THP is considered enabled if it's either "always" or "madvise" */ + return mode == 1 || mode == 3; +} diff --git a/tools/testing/selftests/mm/thp_settings.h b/tools/testing/selftests/mm/thp_settings.h index 876235a23460c..079a58a662b0e 100644 --- a/tools/testing/selftests/mm/thp_settings.h +++ b/tools/testing/selftests/mm/thp_settings.h @@ -84,4 +84,6 @@ void thp_set_read_ahead_path(char *path); unsigned long thp_supported_orders(void); unsigned long thp_shmem_supported_orders(void); +bool thp_is_enabled(void); + #endif /* __THP_SETTINGS_H__ */ -- 2.53.0