From mboxrd@z Thu Jan 1 00:00:00 1970 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 7EFF42853F2 for ; Sat, 20 Dec 2025 11:17:19 +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=1766229441; cv=none; b=oXjRMmQK9aUL0LMvf9MrqcWUJTJ8EogmIbR67k7OL92u65xKa1Nnha99ZwRxsRrm/VmB0uPJfSE4bfvVBgERofo/l0AUEoPTCSbE0WF2aLlAT+uxSq/2icGGyZJnVNTdkzZ4nj31d3fAYEzjm9i6uJ0xkwCEOBvLWJWGsPvgq6A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766229441; c=relaxed/simple; bh=fURT7vwM9crV5rps9En6u63N762gzMQq0l0eUn7sZ3w=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=TROAl+9kdk/u639Q+hrZ1G+SzJWEhLjEpXUIgU7fwQtezGcVWZfpLsNeOOeh6eIbVVjAZ+SilQWsKT9fN2/azkIX2/jgPpWU0O8RWPCBfeD5NOH5DqchLlSpOq0R87U7mCZ34C5zg6PEXM8ILa2fL0+zSHc30ZPFmYMxwxt+TEs= 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=CgBVFs3g; 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="CgBVFs3g" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1766229438; 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=CgBVFs3gekjh2Fs5d1mH2Mr2i0lWR3/77+SdVU8OCh2X0zwREaMKP+kkhzemIaJ5O1JQ1Q 5aM2wAtojGme1SD+q80rHcl0Vkdcct51Ne80Ubg6K0W0rs85QuhKL20DF+DGTDmvb+szVr pFNJR/1bvOTpvKiNmD+rM4RRGa5aaC0= 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-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 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=0 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 = 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=512M,size=0) # 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=${size}, the number of bytes the test will reserve/write, so the filesystem capacity is sufficient regardless of HugeTLB page size. Signed-off-by: Li Wang Cc: David Hildenbrand Cc: Mark Brown Cc: Shuah Khan Cc: Waiman Long --- tools/testing/selftests/mm/charge_reserved_hugetlb.sh | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/mm/charge_reserved_hugetlb.sh b/tools/testing/selftests/mm/charge_reserved_hugetlb.sh index 6aa4ce66922c..9deb3dc2cbce 100755 --- a/tools/testing/selftests/mm/charge_reserved_hugetlb.sh +++ b/tools/testing/selftests/mm/charge_reserved_hugetlb.sh @@ -295,7 +295,7 @@ function run_test() { setup_cgroup "hugetlb_cgroup_test" "$cgroup_limit" "$reservation_limit" mkdir -p /mnt/huge - mount -t hugetlbfs -o pagesize=${MB}M,size=256M none /mnt/huge + mount -t hugetlbfs -o pagesize=${MB}M,size=${size} none /mnt/huge 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_limit2" mkdir -p /mnt/huge - mount -t hugetlbfs -o pagesize=${MB}M,size=256M none /mnt/huge + mount -t hugetlbfs -o pagesize=${MB}M,size=${size} none /mnt/huge write_hugetlbfs_and_get_usage "hugetlb_cgroup_test1" "$size1" \ "$populate1" "$write1" "/mnt/huge/test1" "$method" "$private" \ -- 2.49.0