Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EC500C433EF for ; Tue, 14 Dec 2021 20:57:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234735AbhLNU5x (ORCPT ); Tue, 14 Dec 2021 15:57:53 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38702 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230382AbhLNU5v (ORCPT ); Tue, 14 Dec 2021 15:57:51 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A34B3C061574; Tue, 14 Dec 2021 12:57:51 -0800 (PST) Received: from mail.kernel.org (unknown [198.145.29.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 4415A616F3; Tue, 14 Dec 2021 20:57:51 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 5265A60385; Tue, 14 Dec 2021 20:57:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1639515470; bh=R9qmZKpcT5w0VsfJbKQW4+XRAWTvMIUvc+QUmb73qc8=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=qkPbNuPXw203FLrZEFtUEahnpUOxFmOk2L3oT9K4CLSyOgiR6GX4LNCsTttcIfG2a nviKWftaaWKl4q4oexeadnqveVPKmev7+zRmj3deZqEf/CLSOQFYjtBC77RYNu5MII E9XOQ9/TENrvRwyBdqA2YOZhhjEFyXlyPhmE4HcQ= Date: Tue, 14 Dec 2021 12:57:48 -0800 From: Andrew Morton To: Michal Hocko Cc: Dennis Zhou , Alexey Makhalov , "linux-kernel@vger.kernel.org" , "cl@linux.com" , "mm-commits@vger.kernel.org" , "osalvador@suse.de" , "stable@vger.kernel.org" , "tj@kernel.org" Subject: Re: + mm-fix-panic-in-__alloc_pages.patch added to -mm tree Message-Id: <20211214125748.974a400f0b05a633f9b971b7@linux-foundation.org> In-Reply-To: References: <20211108205031.UxDPHBZWa%akpm@linux-foundation.org> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 14 Dec 2021 11:11:54 +0100 Michal Hocko wrote: > > I need some clarification here. It sounds like memoryless nodes work on > > x86, but hotplug + memoryless nodes isn't a supported use case or you're > > introducing it as a new use case? > > > > If this is a new use case, then I'm inclined to say this patch should > > NOT go in and a proper fix should be implemented on hotplug's side. I > > don't want to be in the business of having/seeing this conversation > > reoccur because we just papered over this issue in percpu. > > The patch still seems to be in the mmotm tree. I have sent a different > fix candidate [1] which should be more robust and cover also other potential > places. > > [1] http://lkml.kernel.org/r/20211214100732.26335-1-mhocko@kernel.org Is cool, I'm paying attention. We do want something short and simple for backporting to -stable (like Alexey's patch) so please bear that in mind while preparing an alternative.