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 E74E032D7D9
	for <linux-kernel@vger.kernel.org>; Mon, 27 Apr 2026 15:12:14 +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=1777302735; cv=none; b=i/LGi62h6rWGrdsuRTa0qqSOWEyX/aXwHjQ3xlV9Cmsxf8AZdhTEShZoDczy/z0FjYcGwc3uDXDi9udTFO/xaAKSALyV1UQjPctvAuu5cecNTX4cx4OHDRG+sefuiqQE+8RIdCKEx6cHex55WQHRD/SU3Dhj0m4Sk/clTA+9apk=
ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org;
	s=arc-20240116; t=1777302735; c=relaxed/simple;
	bh=F2b+BgWCQCTOwW+URnNYXQvaoDUWLyTfvwHMkvbYs0g=;
	h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References:
	 Mime-Version:Content-Type; b=shqfQ4ZjB/C2RGntsvlD0nzgI76nBi6yi/w7pNJx6CWDcRtgYKLEYbtzRHJETtVMvv9egAqyxR0D/xkE+stuhfKDYgA5rAjZVvYfZJDU5cYABgUi2Quq+ir8lmhLScC5h63uR9D2KWYAzQdmfEM85bnuFNXfiwcLdfXpDt5onC8=
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=VNchfyn7; arc=none smtp.client-ip=10.30.226.201
Authentication-Results: smtp.subspace.kernel.org;
	dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="VNchfyn7"
Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7CEB2C19425;
	Mon, 27 Apr 2026 15:12:14 +0000 (UTC)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org;
	s=korg; t=1777302734;
	bh=F2b+BgWCQCTOwW+URnNYXQvaoDUWLyTfvwHMkvbYs0g=;
	h=Date:From:To:Cc:Subject:In-Reply-To:References:From;
	b=VNchfyn7ZVBpAYLhBCWBxxtf0e8OoTwEBd51jJaR8jYrXt0vHVBmMe98eAc6u8FU0
	 79ycQm6zD0OO+mwLfVS4YzPpa3yHKHU+tkO7nBYNEoxytZPzIL0SgGnqzLZZnmyg1P
	 HM/5VD2jpeuI4A4eaSuNg+d1vExW0Pq7k2ZdC98Y=
Date: Mon, 27 Apr 2026 08:12:13 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Catherine <enderaoelyther@gmail.com>
Cc: Muchun Song <muchun.song@linux.dev>, Oscar Salvador <osalvador@suse.de>,
 David Hildenbrand <david@kernel.org>, linux-mm@kvack.org,
 linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm/hugetlb: fix subpool accounting after cgroup charge
 failure
Message-Id: <20260427081213.7935edd49d96622b08e81643@linux-foundation.org>
In-Reply-To: <20260427145247.84157-2-enderaoelyther@gmail.com>
References: <20260427145247.84157-2-enderaoelyther@gmail.com>
X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu)
Precedence: bulk
X-Mailing-List: linux-kernel@vger.kernel.org
List-Id: <linux-kernel.vger.kernel.org>
List-Subscribe: <mailto:linux-kernel+subscribe@vger.kernel.org>
List-Unsubscribe: <mailto:linux-kernel+unsubscribe@vger.kernel.org>
Mime-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit

On Mon, 27 Apr 2026 22:52:48 +0800 Catherine <enderaoelyther@gmail.com> wrote:

> alloc_hugetlb_folio() calls hugepage_subpool_get_pages() when map_chg
> is set.  For subpools with max_hpages, that increments used_hpages even
> when the returned gbl_chg is positive.
> 
> If a later hugetlb cgroup charge fails, the cleanup currently calls
> hugepage_subpool_put_pages() only for !gbl_chg.  The gbl_chg > 0 path
> therefore leaks one used_hpages charge per failure.
> 
> Always undo the subpool charge after a successful subpool get.  Keep the
> global reservation accounting under !gbl_chg, because only that path
> consumed a reservation from the subpool.

Thanks.

We do prefer full, real names for kernel alterations.  Can you please
provide that?