From nobody Tue Sep 29 10:33:01 2026 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 A4B111F16B; Sun, 9 Aug 2026 08:03:45 +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=1786262626; cv=none; b=Tw91jdP3w6Dkqw9CrvYnz8ahaWswE8By91apCxVjDwvsvnRs4DhIZdrC3k5oqOx91WRjodIf7Ul76+96E7tz99f5bdSk66UAfWQ7e5ix111dxKpbHot8KqbhlLmw9QX8tf/l9AVKvpC30jaiMxdl5QXzxzWTBcHEbxdjiSbXQg0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786262626; c=relaxed/simple; bh=W0UcuhIPDeSXz0Fsy1mHSnpDzfBEm8n+bclRDJOKP4M=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:To:Cc; b=jQsYnEdoofPMr1hhByr/n/tcAiYzdxFumUczEz1L7lKMGortfrbqBFtMMUbCYx0QaxjQfxx0r+sf5lc/TzNp6h3aO8d8MOY2WsjdBcdFGi0S7ot/4fhSQQyqtBVsjx8Xdl//vIKFfPdhkgEeKCRc+M/D91OXWpmrl0tRh2Perug= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=eN4rk+K1; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="eN4rk+K1" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 832F91F000E9; Sun, 9 Aug 2026 08:03:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1786262625; bh=UUnD4YT4HuSOBagwB//yv3X0Nx1d1hKHYt4Fov9+dc8=; h=From:Date:Subject:To:Cc; b=eN4rk+K1PFz/8b8/Qu0TTafuUNHxYuoiiH5kdUll/FLdwZtnj3kIbKRy4GfaohDFT XhNKai0vQ/+l02TMioR+oB56F1d+WFZZe4yBhasn1z7GoHNc2q9egVNMDjz2P5Ghgy V2VeBdI+o57IwyRmBXxx1n6hjKyk4SgD911/SoJq5rFpSPZIfjCA7R3ymZK9bXksC+ 4iq9M/NMZFv0DcR/7x5njYxH6geX7j/gtmRP8DNzejUN3qhNRNB83PILJ3Xwprk8px Ppqld6zT+v9L+nNV3i7AHhmcCnvbyHFnBqC5z9rEDB8Th/WdzClA5l1SQVE4XvVAv8 PXYm0tpZfc68Q== From: "Mike Rapoport (Microsoft)" Date: Sun, 09 Aug 2026 11:03:35 +0300 Subject: [PATCH] selftests/mm: thuge-gen: fix test_shmget() for PAGE_SIZE check Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260809-selftests-thuge-gen-fix-v1-1-1919f4b3d12f@kernel.org> X-B4-Tracking: v=1; b=H4sIAFY0eGoC/yWMyw7CIBBFf6WZtROxhvr4FeMCcGgxhRpmMCZN/ 13Q5Tn3sQJTDsRw7VbI9A4cllThsOvATSaNhOFRGXrVD+qsLsg0eyEWRplKjUdK6MMHtXFKez0 c1clBXb8yVf17vt3/zMU+yUm7aw1rmNBmk9zUVIyLxH2MWBKLsTPBtn0B2IuDMZ8AAAA= X-Change-ID: 20260809-selftests-thuge-gen-fix-5ac05f56307c To: Andrew Morton , David Hildenbrand Cc: "Liam R. Howlett" , Lorenzo Stoakes , Michal Hocko , Mike Rapoport , Shuah Khan , Suren Baghdasaryan , Vlastimil Babka , linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org X-Mailer: b4 0.16-dev Commit 49a4e7186b08 ("selftests/mm: thuge-gen: add setup of HugeTLB pages") changed thuge-gen test to use common functions for reading hugetlb attributes from sysfs, but it missed that the original read_free() function special cased PAGE_SIZE tests. For PAGE_SIZE tests, failure to read sysfs was ignored and read_free() returned 0. This allowed test_shmget() to essentially skip the check of how many huge pages was consumed when it ran with PAGE_SIZE. Commit 3199b0c09efa ("selftests/mm: fix read_file() return value check") fixed the common read_file() to actually return error on failure and this exposed the issue in test_shmget() that checks the number of free hugetlb pages even for PAGE_SIZE test, tries to access /sys/kernel/mm/hugepages/hugepages-/free_hugepages and obviously fails there. Gate the checks for free huge pages on size !=3D getpagesize() and initiali= ze before and after variables to values matching PAGE_SIZE test. Fixes: 49a4e7186b08 ("selftests/mm: thuge-gen: add setup of HugeTLB pages") Signed-off-by: Mike Rapoport (Microsoft) Acked-by: David Hildenbrand (Arm) Acked-by: Lorenzo Stoakes (ARM) Reviewed-by: Sarthak Sharma --- selftests/mm: thuge-gen: fix test_shmget() for PAGE_SIZE check --- tools/testing/selftests/mm/thuge-gen.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/tools/testing/selftests/mm/thuge-gen.c b/tools/testing/selftes= ts/mm/thuge-gen.c index 22b9c2f1c35d..50d0805b65db 100644 --- a/tools/testing/selftests/mm/thuge-gen.c +++ b/tools/testing/selftests/mm/thuge-gen.c @@ -71,12 +71,16 @@ void test_mmap(unsigned long size, unsigned flags) =20 void test_shmget(unsigned long size, unsigned flags) { - int id; - unsigned long before, after; + /* values for PAGE_SIZE test */ + unsigned long before =3D NUM_PAGES; + unsigned long after =3D 0; struct shm_info i; char *map; + int id; + + if (size !=3D getpagesize()) + before =3D hugetlb_free_pages(size); =20 - before =3D hugetlb_free_pages(size); id =3D shmget(IPC_PRIVATE, size * NUM_PAGES, IPC_CREAT|0600|flags); if (id < 0) { if (errno =3D=3D EPERM) { @@ -97,10 +101,11 @@ void test_shmget(unsigned long size, unsigned flags) shmctl(id, IPC_RMID, NULL); =20 memset(map, 0xff, size*NUM_PAGES); - after =3D hugetlb_free_pages(size); + if (size !=3D getpagesize()) + after =3D hugetlb_free_pages(size); =20 show(size); - ksft_test_result(size =3D=3D getpagesize() || (before - after) =3D=3D NUM= _PAGES, + ksft_test_result((before - after) =3D=3D NUM_PAGES, "%s: mmap %lu %x\n", __func__, size, flags); if (shmdt(map)) ksft_exit_fail_msg("%s: shmdt: %s\n", __func__, strerror(errno)); --- base-commit: 17e5919bdca144d4e67337f53bf57d7811f62192 change-id: 20260809-selftests-thuge-gen-fix-5ac05f56307c -- Sincerely yours, Mike.