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 DEEE4F43854 for ; Wed, 15 Apr 2026 17:03:18 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 351606B0005; Wed, 15 Apr 2026 13:03:18 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 3024B6B0088; Wed, 15 Apr 2026 13:03:18 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2182E6B0089; Wed, 15 Apr 2026 13:03:18 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 105716B0005 for ; Wed, 15 Apr 2026 13:03:18 -0400 (EDT) Received: from smtpin17.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id B71F01A0586 for ; Wed, 15 Apr 2026 17:03:17 +0000 (UTC) X-FDA: 84661410834.17.5BE3806 Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf25.hostedemail.com (Postfix) with ESMTP id F00F4A000A for ; Wed, 15 Apr 2026 17:03:15 +0000 (UTC) Authentication-Results: imf25.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=L06wAtHS; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf25.hostedemail.com: domain of rppt@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=rppt@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1776272596; 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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=BeK4x1dxgJguKDNqttCCDO06v9f5N1pztpozpFeGrH0=; b=svwB7vuW5cGqOUJy0gmvigtkevs/w22tY4527Y751paCkRJHdiOxnpX7UVnegB0q+wzCnw Y8I3BnGiXY7p1mB/3t0xCEF7ipPa6Zhk/DOkaPBONcU8YBQa5I+1NC2NF4+pgyayK1j7a0 AtSaje1IfJXThSLRjAG65u5yiK9tJnk= ARC-Authentication-Results: i=1; imf25.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=L06wAtHS; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf25.hostedemail.com: domain of rppt@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=rppt@kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1776272596; a=rsa-sha256; cv=none; b=R/BuJ+zDV7igN0zHIdzWND99uceCx/vwjm1gJ7Zm8KpAPtv97JRCsvgHF3VIIpEP2nJ4+d FyOE3uIKWGLDQvPXz6KdEqgC6lNrjLQ3pTAnPm6JPvQX7QKsYfsF1J4ZChrVPA+mYgQtQY /jXAmSW/BQLqOEikabDL3degKUtmNtU= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id 21284600AD; Wed, 15 Apr 2026 17:03:15 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A83C4C19424; Wed, 15 Apr 2026 17:03:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1776272594; bh=mTAGT4DOoB+Ql7bFiOXRTX+ODnCO2UkCTVqe5r/JaGY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=L06wAtHSsRMa8OvFoMaXwNH+1eYa2W/v97alLbMISAOhCVynQoCeVmWJ5ZTbJM2MU QP7uytxhoWHErO3ob8f61vSccJltnPjAWtlZt4lsROLQKwiy6NhoQ5oVgulzUN2XE7 Uo3FI5DmnXnfiqIlq8mgXKJj1rnTTcT/r34LozkpmiTLGt7Qjx1MyAk6v8ee1n+Rpk 74o3/NiC27Orm8AO8F1joPLIciZG77gcb4LXn7GyeQNAW8nrMjUVV+grPXZ+Huzp/Z RmjoqCkMBFE6XBtZkfqKwxw5eGbivNgTzlGo0+AdBKR6c4ga/EKSAl1llk+H4Pev8Q 9k3GwIuIRnuKA== Date: Wed, 15 Apr 2026 20:03:06 +0300 From: Mike Rapoport To: Muchun Song Cc: Andrew Morton , David Hildenbrand , Muchun Song , Oscar Salvador , Michael Ellerman , Madhavan Srinivasan , Lorenzo Stoakes , "Liam R . Howlett" , Vlastimil Babka , Suren Baghdasaryan , Michal Hocko , Nicholas Piggin , Christophe Leroy , aneesh.kumar@linux.ibm.com, joao.m.martins@oracle.com, linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 6/6] mm/mm_init: Fix pageblock migratetype for ZONE_DEVICE compound pages Message-ID: References: <20260415111412.1003526-1-songmuchun@bytedance.com> <20260415111412.1003526-7-songmuchun@bytedance.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260415111412.1003526-7-songmuchun@bytedance.com> X-Rspam-User: X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: F00F4A000A X-Stat-Signature: oegec3kxbwikyatrk8phhxs1jzaqg5m3 X-HE-Tag: 1776272595-177797 X-HE-Meta: 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 FjklkQ3X Fb2o77jkRU54xNhgFmfU7cj3OGSIY11GYG61qAaClhEWm9p34k5CHVjpTWyf326xnNXwAUxQS6+LoS4Gqav2OOV3mP0t0qBMgoGzJgkVsOV2wGvf844AZmNN7l0P0vNY0TRa1BG5yVYXqRal/7/XMSOQOua9AicLXYpQDglBEv0163rsl8a2sEQQHojEu3nDGHdSa35N3Yyn2MkOEDyQaSnqmYHTt/o37vUQjttDwWCTYlfYq9excJM3OdgtUlwj6avp6NI10cmEvgb9EtpxE/4ElsTK8AFA73nojn9BzO+n4sBb4R9xEu34na/ZMuWR+BYgcNXaSrNR4KTziBSSdmIdL3YPNc+H+0mdb Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Hi Muchun, On Wed, Apr 15, 2026 at 07:14:12PM +0800, Muchun Song wrote: > The memmap_init_zone_device() function only initializes the migratetype > of the first pageblock of a compound page. If the compound page size > exceeds pageblock_nr_pages (e.g., 1GB hugepages with 2MB pageblocks), > subsequent pageblocks in the compound page remain uninitialized. > > Move the migratetype initialization out of __init_zone_device_page() > and into a separate pageblock_migratetype_init_range() function. This > iterates over the entire PFN range of the memory, ensuring that all > pageblocks are correctly initialized. > > Fixes: c4386bd8ee3a ("mm/memremap: add ZONE_DEVICE support for compound pages") > Signed-off-by: Muchun Song > --- > mm/mm_init.c | 42 +++++++++++++++++++++++++++--------------- > 1 file changed, 27 insertions(+), 15 deletions(-) > > diff --git a/mm/mm_init.c b/mm/mm_init.c > index f9f8e1af921c..30528c4206c1 100644 > --- a/mm/mm_init.c > +++ b/mm/mm_init.c > @@ -674,6 +674,19 @@ static inline void fixup_hashdist(void) > static inline void fixup_hashdist(void) {} > #endif /* CONFIG_NUMA */ > > +static __meminit void pageblock_migratetype_init_range(unsigned long pfn, > + unsigned long nr_pages, > + int migratetype) > +{ > + unsigned long end = pfn + nr_pages; > + > + for (pfn = pageblock_align(pfn); pfn < end; pfn += pageblock_nr_pages) { > + init_pageblock_migratetype(pfn_to_page(pfn), migratetype, false); > + if (IS_ALIGNED(pfn, PAGES_PER_SECTION)) > + cond_resched(); > + } > +} > + > /* > * Initialize a reserved page unconditionally, finding its zone first. > */ > @@ -1011,21 +1024,6 @@ static void __ref __init_zone_device_page(struct page *page, unsigned long pfn, > page_folio(page)->pgmap = pgmap; > page->zone_device_data = NULL; > > - /* > - * Mark the block movable so that blocks are reserved for > - * movable at startup. This will force kernel allocations > - * to reserve their blocks rather than leaking throughout > - * the address space during boot when many long-lived > - * kernel allocations are made. > - * > - * Please note that MEMINIT_HOTPLUG path doesn't clear memmap > - * because this is done early in section_activate() > - */ > - if (pageblock_aligned(pfn)) { > - init_pageblock_migratetype(page, MIGRATE_MOVABLE, false); > - cond_resched(); > - } > - > /* > * ZONE_DEVICE pages other than MEMORY_TYPE_GENERIC are released > * directly to the driver page allocator which will set the page count > @@ -1122,6 +1120,8 @@ void __ref memmap_init_zone_device(struct zone *zone, > > __init_zone_device_page(page, pfn, zone_idx, nid, pgmap); > > + cond_resched(); > + I don't think we want cond_resched() for every page here too, even it's a compound page :) Otherwise Reviewed-by: Mike Rapoport (Microsoft) > if (pfns_per_compound == 1) > continue; > > @@ -1129,6 +1129,18 @@ void __ref memmap_init_zone_device(struct zone *zone, > compound_nr_pages(altmap, pgmap)); > } > > + /* > + * Mark the block movable so that blocks are reserved for > + * movable at startup. This will force kernel allocations > + * to reserve their blocks rather than leaking throughout > + * the address space during boot when many long-lived > + * kernel allocations are made. > + * > + * Please note that MEMINIT_HOTPLUG path doesn't clear memmap > + * because this is done early in section_activate() > + */ > + pageblock_migratetype_init_range(start_pfn, nr_pages, MIGRATE_MOVABLE); > + > pr_debug("%s initialised %lu pages in %ums\n", __func__, > nr_pages, jiffies_to_msecs(jiffies - start)); > } > -- > 2.20.1 > -- Sincerely yours, Mike.