From nobody Mon Feb 9 04:12:36 2026 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 9E57A2D46B4 for ; Sat, 20 Dec 2025 11:17:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766229440; cv=none; b=IvxM7Z9eP2mWkkHGgdPRPGJC3X2PFCWFNTguJyjkWEQ0xXY3kAVr9oMmgaXX+g+BNO6IjTCgzN80iByePC0OmmBE6rdS1maqfUqT0JT5JgNgEXCRGb8f/qx2KGUZveKGh76FMGN+ZERKocMJpN5KR5hFVyTk32A49fQ2ONiRyUc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766229440; c=relaxed/simple; bh=fURT7vwM9crV5rps9En6u63N762gzMQq0l0eUn7sZ3w=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DfaUZy6e42Ay9brEinCXs91EDLGdw/515yl+oihGvjknPoiEeMpG+5OmIlBa1AK2fK7UEeuT2PDBF5pmfL4RkDoNiarP2jQJMIFsMJNM5oftA9shJmQ2Uw5m1ER10feqKcLBQhHpwOtlScQBzh6nbWYbDpvSTj26BRyE6zV6Hzw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=X+JhSh+g; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="X+JhSh+g" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1766229437; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=AeYBXDIL9p75os/GitpdF41KNLUSWbRtlTHaY5hYAc0=; b=X+JhSh+gqQu59bzbBVCrDna0p6AqXoI2zbDaxGUKH8l5H1H78qAPVohyQlf3eYbxaG2KCm n2izhIzi+OuiW14hVDWjbsfymv5TbHc2QHJKgR7wfY8KqRF1SCd8TxCvvU7IP8Qcku97ef T8jOkk2YPu4RM6Hm19zdVqvj3XaBTdU= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-690-Sm7oz34fNhKy_ydVLDNVhg-1; Sat, 20 Dec 2025 06:17:11 -0500 X-MC-Unique: Sm7oz34fNhKy_ydVLDNVhg-1 X-Mimecast-MFC-AGG-ID: Sm7oz34fNhKy_ydVLDNVhg_1766229430 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 72A18195DE56; Sat, 20 Dec 2025 11:17:10 +0000 (UTC) Received: from dell-per7425-02.rhts.eng.pek2.redhat.com (dell-per7425-02.rhts.eng.pek2.redhat.com [10.73.116.18]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 02FA9180066C; Sat, 20 Dec 2025 11:17:06 +0000 (UTC) From: Li Wang To: linux-kselftest@vger.kernel.org, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: David Hildenbrand , Mark Brown , Shuah Khan , Waiman Long Subject: [PATCH 3/3] selftests/mm/charge_reserved_hugetlb: fix hugetlbfs mount size for large hugepages Date: Sat, 20 Dec 2025 19:16:45 +0800 Message-ID: <20251220111645.2246009-4-liwang@redhat.com> In-Reply-To: <20251220111645.2246009-1-liwang@redhat.com> References: <20251220111645.2246009-1-liwang@redhat.com> 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-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 Content-Type: text/plain; charset="utf-8" charge_reserved_hugetlb.sh mounts a hugetlbfs instance at /mnt/huge with a fixed size of 256M. On systems with large base hugepages (e.g. 512MB), this is smaller than a single hugepage, so the hugetlbfs mount ends up with effectively zero capacity (often visible as size=3D0 in mount output). As a result, write_to_hugetlbfs fails with ENOMEM and the test can hang waiting for progress. --- Error log --- # uname -r 6.12.0-xxx.el10.aarch64+64k #./charge_reserved_hugetlb.sh -cgroup-v2 # ----------------------------------------- ... # nr hugepages =3D 10 # writing cgroup limit: 5368709120 # writing reseravation limit: 5368709120 ... # write_to_hugetlbfs: Error mapping the file: Cannot allocate memory # Waiting for hugetlb memory reservation to reach size 2684354560. # 0 # Waiting for hugetlb memory reservation to reach size 2684354560. # 0 ... # mount |grep /mnt/huge none on /mnt/huge type hugetlbfs (rw,relatime,seclabel,pagesize=3D512M,si= ze=3D0) # grep -i huge /proc/meminfo ... HugePages_Total: 10 HugePages_Free: 10 HugePages_Rsvd: 0 HugePages_Surp: 0 Hugepagesize: 524288 kB Hugetlb: 5242880 kB Mount hugetlbfs with size=3D${size}, the number of bytes the test will reserve/write, so the filesystem capacity is sufficient regardless of HugeTLB page size. Signed-off-by: Li Wang Cc: David Hildenbrand Cc: Mark Brown Cc: Shuah Khan Cc: Waiman Long --- tools/testing/selftests/mm/charge_reserved_hugetlb.sh | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/mm/charge_reserved_hugetlb.sh b/tools/= testing/selftests/mm/charge_reserved_hugetlb.sh index 6aa4ce66922c..9deb3dc2cbce 100755 --- a/tools/testing/selftests/mm/charge_reserved_hugetlb.sh +++ b/tools/testing/selftests/mm/charge_reserved_hugetlb.sh @@ -295,7 +295,7 @@ function run_test() { setup_cgroup "hugetlb_cgroup_test" "$cgroup_limit" "$reservation_limit" =20 mkdir -p /mnt/huge - mount -t hugetlbfs -o pagesize=3D${MB}M,size=3D256M none /mnt/huge + mount -t hugetlbfs -o pagesize=3D${MB}M,size=3D${size} none /mnt/huge =20 write_hugetlbfs_and_get_usage "hugetlb_cgroup_test" "$size" "$populate" \ "$write" "/mnt/huge/test" "$method" "$private" "$expect_failure" \ @@ -349,7 +349,7 @@ function run_multiple_cgroup_test() { setup_cgroup "hugetlb_cgroup_test2" "$cgroup_limit2" "$reservation_limit= 2" =20 mkdir -p /mnt/huge - mount -t hugetlbfs -o pagesize=3D${MB}M,size=3D256M none /mnt/huge + mount -t hugetlbfs -o pagesize=3D${MB}M,size=3D${size} none /mnt/huge =20 write_hugetlbfs_and_get_usage "hugetlb_cgroup_test1" "$size1" \ "$populate1" "$write1" "/mnt/huge/test1" "$method" "$private" \ --=20 2.49.0