From mboxrd@z Thu Jan 1 00:00:00 1970 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 548B3C5516F for ; Fri, 31 Jul 2026 15:55:28 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 734D56B008A; Fri, 31 Jul 2026 11:55:27 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 70BC86B0095; Fri, 31 Jul 2026 11:55:27 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6482A6B009E; Fri, 31 Jul 2026 11:55:27 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 4B92F6B008A for ; Fri, 31 Jul 2026 11:55:27 -0400 (EDT) Received: from smtpin12.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay09.hostedemail.com (Postfix) with ESMTP id D070A80462 for ; Fri, 31 Jul 2026 15:55:26 +0000 (UTC) X-FDA: 85049521452.12.8C134ED Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf27.hostedemail.com (Postfix) with ESMTP id 107474000C for ; Fri, 31 Jul 2026 15:55:24 +0000 (UTC) Authentication-Results: imf27.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=aQrz+q+j; spf=pass (imf27.hostedemail.com: domain of ljs@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=ljs@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1785513325; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=rV8nBJFnfG2GCaRpLts+gSbWqrdQBPDmfooT330Oc+A=; b=qkA/+gQjk0j723fRHezR5N6qMznSYaqhCjVvjTXvA0AENK/BGMkbC0lz+MyJZ2ZeZjp+SK AXRQieItrcdefDpEl/PjsC/0ibJ5kFFM2bQPAvoLzX/VPmlj0EEHl1dnY4HsK6acY6N+Tw nAA9lZE08CY5DEc0m47nFJUjVFJuQnc= ARC-Authentication-Results: i=1; imf27.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=aQrz+q+j; spf=pass (imf27.hostedemail.com: domain of ljs@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=ljs@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1785513325; b=P5bXcFQ/YZNxpFzklRfFGEWuap7RKFw0PwrmxpVVS7pw58yrFpmQXkoUeqGCOVORdoUvsK ZNIDfLsmDp25EqJyI/h5vLcLYnQft2SG+GFel1VwI0S9xZ8ZyJb1KCSu5N2oStvg1ad4AK xVdC2snL1VMPfO14XhOLZRtTjSlGJmY= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id DABA66004E; Fri, 31 Jul 2026 15:55:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2740C1F00AC4; Fri, 31 Jul 2026 15:55:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785513323; bh=rV8nBJFnfG2GCaRpLts+gSbWqrdQBPDmfooT330Oc+A=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=aQrz+q+jmtWscHrp9E+JMtT7juGxIgBJ3k9QargV1FyQBz2ttEjM99JD/jGxdWEGw /c5KRx/P0sBey4T/Qy/3YB6loaZcpj+tPfwVDTGjIue0RhaFOU1Gp7IAYSxDt8vntP MJnrnfKJHRSm2RQeLZcuO47Ak1d92ouTrk6J+jywUfIPCc8mLnKQgHG5tsD+pOUh13 b0prcn+AFcDCYUGCq+lzyhJLdEBoO9LLM2D+Ib6/Sfncw8dJA8BdUY+Fq7gDh+LoJO mF4ExPOvMNBpc/WnbTG583ancA4tYXxxFUDSZwNsxBiMmBsvCLKRmT+Gt0ylRSi04/ IoTfI8rPInNoA== Date: Fri, 31 Jul 2026 16:55:05 +0100 From: "Lorenzo Stoakes (ARM)" To: Juan Yescas Cc: "David Hildenbrand (Arm)" , Andrew Morton , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , open list , "open list:MEMORY MANAGEMENT - CORE" , android-mm@google.com, fvdl@google.com, tkjos@google.com, minchan@google.com, dskiba@google.com Subject: Re: [RFC PATCH 00/16] Page Alloc Hogger Message-ID: References: <20260723074854.1013941-1-jyescas@google.com> <97605949-82c5-49e0-84b6-b42e8078b55d@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Rspam-User: X-Rspamd-Queue-Id: 107474000C X-Rspamd-Server: rspam01 X-Stat-Signature: mgfgnu7hkken9dg7opgubtjzy9dwk4uc X-HE-Tag: 1785513324-465125 X-HE-Meta: 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 1dh5rytP 7rTHhSsU5hw0G8vQ65HwJPMuhXyw9JP0LPHjpX0iwCnbWZ/9Mm0CtuGWe3Gj3ABCtkc6/QhXxyHsVCR6VLZI8mfWWwFIOdCgir78x8cH6dGb8U4OtvveHGaMh+05VQ37uLnrGjaO5NhqsF58r2pQTD5kjwh4uI0CITH4HXtq0U01A3GEFs3S1StCkXKJ8foFw25hoEOfTzqQHM3lFJjg9+g2A8eG7tEulaNCGndNLJkWUtJwr1PQMn8bvuuBea19UhpllXxDoM1cdtBR8TkBTObs4RTHstbhgtBaaRuidBAtwGw1Bu4jOQ2Scmi/7AUR+6onTqhR9GRJaQMAcYmTIEj3Obb9VGxl7nLbCI9P+iGixIRyMEGsAdooM/g== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, Jul 31, 2026 at 08:32:35AM -0700, Juan Yescas wrote: > On Thu, Jul 30, 2026 at 12:51 AM Lorenzo Stoakes (ARM) wrote: > > > > On Tue, Jul 28, 2026 at 05:36:03PM -0700, Juan Yescas wrote: > > > On Tue, Jul 28, 2026 at 12:29 PM David Hildenbrand (Arm) > > > wrote: > > > > > > > > On 7/23/26 09:47, Juan Yescas wrote: > > > > > This patch series introduces the Page Alloc Hogger. The Page Alloc Hogger > > > > > allows you to allocate memory pages from specific nodes, zones, migration > > > > > types, and orders directly via debugfs. This provides key benefits for > > > > > testing and debugging: > > > > > > > > Would it be feasible to carry this as an OOT debugging module? Would a lot of > > > > symbols be missing to achieve that? > > > > > > > > > > Thanks David for the comment. > > > > > > The only symbol that would be needed to have this module as OOT is > > > "migratetype_names". > > > > I mean you could hardcode these and be pretty safe :) I don't we're going > > to add any time soon and if we did you'd probably need to change the module > > code anyway? > > Thanks Lorenzo, I agree, the names can be hardcoded. Yeah :) I think not such an issue. > > > I feel this debug module should be a noop in core. > > What would be the main concern here? > > The reason I wrote this module is because my team and system teams who > work in memory, > have programs to alloc/free memory to debug memory issues. These > programs are not shared and > depending on the memory issue, developers customize their programs. If we want > to allocate memory that is not MOVABLE, we need to write custom kernel > drivers for that. This code > is reinvented constantly by developers. Exposing internal implementation details via debugfs is problematic as a core feature. It's not impossible for this to be upstream however as a separate driver on the basis of people re-inventing? > > With this self contained module, we can allocate any valid memory from > any node/zone/order/migrate type > without needing custom programs or drivers. > > Greetings > Juan > > > Cheers, Lorenzo -- Cheers, Lorenzo