From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 94C76186A; Sun, 21 Dec 2025 09:17:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766308637; cv=none; b=l2HM57AEEPwZsjBa8wzPAZIYJKtO0iYZm4KXvtFGhKPyJCV5BZAVXzhFsj972Ecfz+YzWfVqWY+OHa9BVg3hyMf9e+CZzCfbtJpQhdOgEKHjoavRn3JyAD08iHeBW2yVbRQzxA6IuiJxq2WAvKkiYHz/QR+Cg0Q5Dvg3oe/MH/w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766308637; c=relaxed/simple; bh=4eUA6zMGUNJWxe38oDOSWKwnrNVk4Nx/VqQvXb9wl/k=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=B2LZ2hKZr40+/BzwvSYeKWM06JfuG+zIkzAUaNRw9WuGvkr/P4lp129dfZaaom0rtrRcJBX314JN6Q9IfNFbPvZ5zQtjIIaD65UrGhc9ecuWOTgpdpsw+g/5wLUt9Gp3bZ3u61P+BFP47H9FMoaxlR6Wp0YEerU0kxLsgubRAYU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=nEWtcsSM; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="nEWtcsSM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F04EEC4CEFB; Sun, 21 Dec 2025 09:17:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1766308637; bh=4eUA6zMGUNJWxe38oDOSWKwnrNVk4Nx/VqQvXb9wl/k=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=nEWtcsSMv3X8IEXCQ8ilT++XBsGdu99zZSG4GQRMRicqoAG6z7D4s6Sjcs2zUs3Gi MnOPLHswFOUldvFzErPD/etpuQLMhf2/vK/MCoP+HH8USOFpWUxMmUZDE+Hp9J8AIN XUF+AUjgp1z3J7udB81iSZwKamO0vXN24lvP37+viWs33PipIh9TX4YCM+6RAvnEUO mhITa188sLjIon2/QrFf6fH/KWGXOddMJ/7xOQJRQ8wVMEXEEkaAad7A5SJdrJ3Fhf WZBk4EVYR3+do0mkL5Ns2xDjdTsgxUTQbFgg7vIqmzq1CyJUAWsfgLHfZkVWnriwiQ wF4vF/1jj41GA== Message-ID: <970fa015-9ec8-4903-8e2f-f3e847d550d1@kernel.org> Date: Sun, 21 Dec 2025 10:17:12 +0100 Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 3/3] selftests/mm/charge_reserved_hugetlb: fix hugetlbfs mount size for large hugepages To: Li Wang , akpm@linux-foundation.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: Mark Brown , Shuah Khan , Waiman Long References: <20251221085810.3163919-1-liwang@redhat.com> <20251221085810.3163919-4-liwang@redhat.com> From: "David Hildenbrand (Red Hat)" Content-Language: en-US In-Reply-To: <20251221085810.3163919-4-liwang@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 12/21/25 09:58, Li Wang wrote: > 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. I'm curious, what's the history of using "256MB" in the first place (or specifying any size?). -- Cheers David