From mboxrd@z Thu Jan 1 00:00:00 1970 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 DBC27411660; Mon, 14 Sep 2026 08:40:36 +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=1789375241; cv=none; b=A67BQBIa1e8VJDgIilVXm3fwUIEkb0jWMJtCiVnyE/+Sz+Elb9GUKILpYoZW7yoduIIKd68zWysXSNQXjA8Px9BhUm8AHsp7qpOk+Je7DlFcshnjoqs01DppUdPr+N64GCt3ad9kvzlGJmWsHGanV0kYcdRKCboLqCcrUpnBiU4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789375241; c=relaxed/simple; bh=Dx0wwqtveMRIR1J9nZSwoaIXurSfK88RSfnle5PZNh4=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=GpLSmrNCDzqrTgBi4kxgRkGsj/G8Y0YskU8OBiMRhYosc6NWCxn5Tx/ZBZbvtmDu842xTrB8YTIXLEqmdFl2YXJL8/F8hBflmxV+ATjOQ6SuSyPoF+fcgslUsEKHaLJRr2KGWi0UgA8KInEiZ9cAPvVDv2ze9UbgFhhe74KwY4Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=mNtOK2zs; 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="mNtOK2zs" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C67FF1F000FF; Mon, 14 Sep 2026 08:40:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789375234; bh=Iyik9pk4XQ9fStO+xDvNhhL7n3Rs9lsYxmsRtmeHa2A=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=mNtOK2zs39vecG0w1gV1ZnGXxRSeRhGGgqdGu9C+NM5+QMhmLwXfog7KDPTX5FhAN sUqTEKqoc8GCZ2uy/5GPTJRdvj6urd/ewZrwgExOdw6dTYAUwNLYqlgmZGT114Q2mt Z/cEITyN2ePCcRmheffC0W1ysHCgQvMYh/mAovZSiDi5WfPoZ1O8XV8EgamBr02v+S /TCyWIa0QOdVO7NZlzDj5HRxmcNgmKBlhrI3WBcu30iyJyYVlozAW1e4HYhGzqp3LF v/4uqGKQp29b3+pXeda8RNL380V9tRU28bGrztLCwN8h0VdDaRXgJ1afEnd2gxZ+L2 i1i6nk5UGcg2Q== Message-ID: <80686bbf-f174-43c4-99e4-0257d513281a@kernel.org> Date: Mon, 14 Sep 2026 10:40:28 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH] mm/memory_hotplug: use public nodes for migration targets To: "Zimo.Lu" , Gregory Price Cc: Oscar Salvador , Andrew Morton , linux-mm@kvack.org, linux-cxl@vger.kernel.org, linux-kernel@vger.kernel.org References: <20260914074323.3567923-1-louis2665573906@gmail.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 9/14/26 09:43, Zimo.Lu wrote: > do_migrate_range() excludes the source node from node_states[N_MEMORY] > and adds it back only when the nmask is empty. With private nodes in > N_MEMORY, this can leave a nonempty nmask containing only private nodes, > when the system has only one public node and others are private nodes. > Ordinary migration allocations use the public fallback zonelist, so none > of those nodes can satisfy the allocation. > > Build the nmask from N_MEMORY_PUBLIC so that private nodes do not prevent > this fallback. > > For HugeTLB migration during memory offlining, this also excludes other > private nodes from the nmask when the source node is private and public > nodes are present. > > Signed-off-by: Zimo.Lu > Assisted-by: LLM > --- This should be discussed in the relevant patch set. -- Cheers, David