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 8EB6F48595D for ; Tue, 13 Oct 2026 04:33:46 +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=1791866034; cv=none; b=PwxzarhfXnqLror8q9j8+H5MGBxg3mYeVuaizKaY48Zcupwq8vSRJm6XnKgZ1Bqb01gltp6xpB0rXdXMeS45jdaA4wNM5US18HNOyZp5sGwy9wUx2cyf9YUSJCOkbmol/gdcLzRp3R4N51J6AiZRkUrjk1l0DG8cOZd21Bj/NOg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791866034; c=relaxed/simple; bh=sCdLT2dqzjVIwz7nWSVDs6TbXNg9V5EARIinsVcrqZI=; h=Date:To:From:Subject:Message-Id; b=YU+PCLspzHx7i/s6W3B3IJWLNmOWDBnONCOVjZ2VniOh2fbSMdihosCe9EB7GoymdntATURiWW3zQKtJU/cd7CpKmnjHGmotVXbnDOf/Hftqg14KCRMEvNN3/SN5K/w0pG9B+HTIDAXaz0aGIDVasHVGjwPAggCAdVYsBYeRw2I= 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=eZ3u7cXW; 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="eZ3u7cXW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5BBAD1F0089B; Tue, 13 Oct 2026 04:33:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1791866026; bh=kaTnhhKBiirbM+VyR4HT8OKEAetg4uBu0tYFZl/Fcow=; h=Date:To:From:Subject; b=eZ3u7cXWW7L7Sa4Id/kuJk/1/o+PYEuAds4Oa96HkpTNj1XcOTuBpjVnHWH9Frkzo TWhg/x3mQ+kl7ZxvSMZeYscnslsbypGyfIyShiYtxsV2N8j3cQtMMxmip9mSniiuoS M8kl/0i09NpQiS0JsIuUPepofg8W/z81qCGRnX2U= Date: Mon, 12 Oct 2026 21:33:45 -0700 To: mm-commits@vger.kernel.org,ziy@nvidia.com,vbabka@kernel.org,usama.arif@linux.dev,usama.anjum@arm.com,surenb@google.com,shuah@kernel.org,ryan.roberts@arm.com,rppt@kernel.org,nico.pache@linux.dev,mhocko@suse.com,ljs@kernel.org,liam@infradead.org,leon@kernel.org,lance.yang@linux.dev,kernel-team@meta.com,jgg@ziepe.ca,hughd@google.com,dev.jain@arm.com,david@kernel.org,baolin.wang@linux.alibaba.com,baohua@kernel.org,agordeev@linux.ibm.com,kas@kernel.org,akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-stable] selftests-mm-add-folio-order-detection-self-check.patch removed from -mm tree Message-Id: <20261013043346.5BBAD1F0089B@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The quilt patch titled Subject: selftests/mm: add folio-order detection self-check has been removed from the -mm tree. Its filename was selftests-mm-add-folio-order-detection-self-check.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: "Kiryl Shutsemau (Meta)" Subject: selftests/mm: add folio-order detection self-check Date: Sat, 19 Sep 2026 01:24:39 +0100 The khugepaged mTHP tests detect collapse results with the vm_util folio-order helpers rather than smaps AnonHugePages, which only sees PMD mappings. If those helpers are wrong, every case built on them is wrong the same way, and nothing says so. Check them directly. For every anon THP order the kernel supports, fault memory in with only that order enabled. Require the helpers to classify the backing as exactly that order: not the order below it, and base-page memory as order 0. Run it in the thp category, ahead of ./khugepaged, so a broken helper is reported as itself rather than as a collapse failure. Verified on x86-64 4K (orders 0, 2-9) and arm64 64K (orders 0, 2-13). The test needs ALIGN(), which hmm-tests.c and migration.c each defined privately. Move it to vm_util.h and drop both copies. Link: https://lore.kernel.org/20260919002451.496763-10-kirill@shutemov.name Signed-off-by: Kiryl Shutsemau (Meta) Signed-off-by: Andrew Morton Tested-by: Muhammad Usama Anjum Assisted-by: LLM Cc: Alexander Gordeev Cc: Baolin Wang Cc: Barry Song Cc: "David Hildenbrand (arm)" Cc: Dev Jain Cc: Hugh Dickens Cc: Jason Gunthorpe Cc: kernel-team@meta.com Cc: Lance Yang Cc: Leon Romanovsky Cc: Liam Howlett Cc: Lorenzo Stoakes (ARM) Cc: Michal Hocko Cc: Mike Rapoport (Microsoft) Cc: Nico Pache (Red Hat) Cc: Ryan Roberts Cc: Shuah Khan (Samsung OSG) Cc: Suren Baghdasaryan Cc: Usama Arif Cc: "Vlastimil Babka (SUSE)" Cc: Zi Yan --- tools/testing/selftests/mm/Makefile | 1 tools/testing/selftests/mm/folio_order_check.c | 122 +++++++++++++++ tools/testing/selftests/mm/hmm-tests.c | 1 tools/testing/selftests/mm/migration.c | 1 tools/testing/selftests/mm/run_vmtests.sh | 2 tools/testing/selftests/mm/vm_util.h | 2 6 files changed, 127 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/mm/folio_order_check.c a/tools/testing/selftests/mm/folio_order_check.c new file mode 100644 --- /dev/null +++ a/tools/testing/selftests/mm/folio_order_check.c @@ -0,0 +1,122 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Self-check for the vm_util folio-order helpers, is_backed_by_folio() and + * is_range_backed_by_order(), which the khugepaged mTHP cases use to detect + * collapse results. For every anon THP order the kernel supports, fault + * memory in with only that order enabled and require the helpers to report + * exactly that order. + */ +#define _GNU_SOURCE +#include +#include +#include +#include +#include + +#include "kselftest.h" +#include "vm_util.h" +#include + +static int pagemap_fd; +static int kpageflags_fd; + +static char *alloc_aligned(size_t size) +{ + size_t len = size * 2; + char *p, *aligned; + + p = mmap(NULL, len, PROT_READ | PROT_WRITE, + MAP_ANONYMOUS | MAP_PRIVATE, -1, 0); + if (p == MAP_FAILED) + ksft_exit_fail_perror("mmap()"); + + aligned = (char *)ALIGN((uintptr_t)p, size); + if (aligned != p) + munmap(p, aligned - p); + if (aligned + size != p + len) + munmap(aligned + size, p + len - aligned - size); + + return aligned; +} + +static void check_order(int order) +{ + struct thp_settings settings = *thp_current_settings(); + size_t size = psize() << order; + bool ok = true; + char *p; + int i; + + for (i = 0; i < NR_ORDERS; i++) + settings.hugepages[i].enabled = THP_NEVER; + if (order) + settings.hugepages[order].enabled = THP_ALWAYS; + thp_push_settings(&settings); + + p = alloc_aligned(size); + *p = 1; + + if (!is_range_backed_by_order(p, size, order, pagemap_fd, kpageflags_fd)) { + ksft_print_msg("order %d not detected after fault\n", order); + ok = false; + } + + /* A lower order must be rejected: the folio is larger */ + if (order && is_range_backed_by_order(p, size, order - 1, + pagemap_fd, kpageflags_fd)) { + ksft_print_msg("order %d also reported as order %d\n", + order, order - 1); + ok = false; + } + + /* A large folio must not pass as order 0 */ + if (order && is_range_backed_by_order(p, size, 0, + pagemap_fd, kpageflags_fd)) { + ksft_print_msg("order %d also reported as order 0\n", order); + ok = false; + } + + munmap(p, size); + thp_pop_settings(); + + ksft_test_result(ok, "order %d classified\n", order); +} + +int main(void) +{ + struct thp_settings settings; + unsigned long orders; + int order; + + ksft_print_header(); + + if (!thp_available()) + ksft_exit_skip("Transparent Hugepages not available\n"); + + pagemap_fd = open("/proc/self/pagemap", O_RDONLY); + if (pagemap_fd < 0) + ksft_exit_fail_perror("open(/proc/self/pagemap)"); + kpageflags_fd = open("/proc/kpageflags", O_RDONLY); + if (kpageflags_fd < 0) + ksft_exit_skip("open(/proc/kpageflags) requires root\n"); + + orders = thp_supported_orders(); + if (!orders) + ksft_exit_skip("No supported THP orders\n"); + + ksft_set_plan(__builtin_popcountl(orders) + 1); + + thp_save_settings(); + thp_read_settings(&settings); + /* Base of the settings stack; the bottom entry is never popped */ + thp_push_settings(&settings); + + check_order(0); + for (order = 1; order < NR_ORDERS; order++) { + if (!(orders & (1UL << order))) + continue; + check_order(order); + } + + ksft_finished(); +} --- a/tools/testing/selftests/mm/hmm-tests.c~selftests-mm-add-folio-order-detection-self-check +++ a/tools/testing/selftests/mm/hmm-tests.c @@ -65,7 +65,6 @@ enum { #define HMM_PATH_MAX 64 #define NTIMES 10 -#define ALIGN(x, a) (((x) + (a - 1)) & (~((a) - 1))) /* Just the flags we need, copied from mm.h: */ #ifndef FOLL_WRITE --- a/tools/testing/selftests/mm/Makefile~selftests-mm-add-folio-order-detection-self-check +++ a/tools/testing/selftests/mm/Makefile @@ -105,6 +105,7 @@ TEST_GEN_FILES += guard-regions TEST_GEN_FILES += merge TEST_GEN_FILES += rmap TEST_GEN_FILES += folio_split_race_test +TEST_GEN_FILES += folio_order_check TEST_GEN_FILES += soft-dirty ifeq ($(ARCH),x86_64) --- a/tools/testing/selftests/mm/migration.c~selftests-mm-add-folio-order-detection-self-check +++ a/tools/testing/selftests/mm/migration.c @@ -20,7 +20,6 @@ #define TWOMEG (2<<20) #define RUNTIME (20) -#define ALIGN(x, a) (((x) + (a - 1)) & (~((a) - 1))) HUGETLB_SETUP_DEFAULT_PAGES(1) --- a/tools/testing/selftests/mm/run_vmtests.sh~selftests-mm-add-folio-order-detection-self-check +++ a/tools/testing/selftests/mm/run_vmtests.sh @@ -382,6 +382,8 @@ CATEGORY="pfnmap" run_test ./pfnmap # COW tests CATEGORY="cow" run_test ./cow +CATEGORY="thp" run_test ./folio_order_check + CATEGORY="thp" run_test ./khugepaged CATEGORY="thp" run_test ./khugepaged -s 2 --- a/tools/testing/selftests/mm/vm_util.h~selftests-mm-add-folio-order-detection-self-check +++ a/tools/testing/selftests/mm/vm_util.h @@ -12,6 +12,8 @@ #include #define BIT_ULL(nr) (1ULL << (nr)) +#define ALIGN(x, a) (((x) + (a) - 1) & ~((a) - 1)) + #define PM_SOFT_DIRTY BIT_ULL(55) #define PM_MMAP_EXCLUSIVE BIT_ULL(56) #define PM_UFFD_WP BIT_ULL(57) _ Patches currently in -mm which might be from kas@kernel.org are mm-page_alloc-make-defrag_mode-retries-follow-the-promoted-order.patch mm-khugepaged-drop-redundant-mm_struct-pin-in-madvise_collapse.patch mm-khugepaged-count-collapses-where-khugepaged-makes-them.patch mm-khugepaged-rename-mthp_present_ptes-bitmap-to-eligible_ptes.patch mm-collapse-add-collapseh-for-the-collapse-interface.patch mm-collapse-state-what-a-collapse-may-do-in-the-policy.patch mm-collapse-drop-the-collapse_possible-wrapper.patch mm-collapse-name-the-per-table-scan-reset-for-what-it-resets.patch mm-collapse-call-collapse_file-from-collapse_single_pmd.patch mm-collapse-separate-scanning-a-pte-table-from-collapsing-it.patch mm-collapse-open-code-collapse_single_pmd-in-its-two-callers.patch mm-collapse-work-out-the-orders-a-vma-allows-once-per-vma.patch mm-collapse-declare-the-collapse-interface-in-collapseh.patch mm-collapse-implement-madv_collapse-in-madvisec.patch