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 X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 53F1AC433E2 for ; Mon, 15 Jun 2020 03:54:09 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 1794D207BC for ; Mon, 15 Jun 2020 03:54:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1794D207BC Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-m68k.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 77DCD6B000C; Sun, 14 Jun 2020 23:54:08 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 72F136B000D; Sun, 14 Jun 2020 23:54:08 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 645156B000E; Sun, 14 Jun 2020 23:54:08 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0046.hostedemail.com [216.40.44.46]) by kanga.kvack.org (Postfix) with ESMTP id 4C9086B000C for ; Sun, 14 Jun 2020 23:54:08 -0400 (EDT) Received: from smtpin27.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 0179E181AC9C6 for ; Mon, 15 Jun 2020 03:54:08 +0000 (UTC) X-FDA: 76930078176.27.ducks24_4205f2b26df3 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin27.hostedemail.com (Postfix) with ESMTP id D28F73D663 for ; Mon, 15 Jun 2020 03:54:07 +0000 (UTC) X-HE-Tag: ducks24_4205f2b26df3 X-Filterd-Recvd-Size: 7114 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf16.hostedemail.com (Postfix) with ESMTP for ; Mon, 15 Jun 2020 03:54:07 +0000 (UTC) Received: from [10.44.0.192] (unknown [103.48.210.53]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 291D120768; Mon, 15 Jun 2020 03:53:45 +0000 (UTC) To: rppt@kernel.org Cc: Hoan@os.amperecomputing.com, James.Bottomley@HansenPartnership.com, akpm@linux-foundation.org, bcain@codeaurora.org, bhe@redhat.com, catalin.marinas@arm.com, corbet@lwn.net, dalias@libc.org, davem@davemloft.net, deller@gmx.de, geert@linux-m68k.org, green.hu@gmail.com, guoren@kernel.org, gxt@pku.edu.cn, heiko.carstens@de.ibm.com, jcmvbkbc@gmail.com, ley.foon.tan@intel.com, linux-alpha@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-c6x-dev@linux-c6x.org, linux-csky@vger.kernel.org, linux-doc@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-mm@kvack.org, linux-parisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-um@lists.infradead.org, linux-xtensa@linux-xtensa.org, linux@armlinux.org.uk, linuxppc-dev@lists.ozlabs.org, mattst88@gmail.com, mhocko@kernel.org, monstr@monstr.eu, mpe@ellerman.id.au, msalter@redhat.com, nickhu@andestech.com, openrisc@lists.librecores.org, paul.walmsley@sifive.com, richard@nod.at, rppt@linux.ibm.com, shorne@gmail.com, sparclinux@vger.kernel.org, tony.luck@intel.com, tsbogend@alpha.franken.de, uclinux-h8-devel@lists.sourceforge.jp, vgupta@synopsys.com, x86@kernel.org, ysato@users.sourceforge.jp References: <20200412194859.12663-5-rppt@kernel.org> Subject: Re: [PATCH 04/21] mm: free_area_init: use maximal zone PFNs rather than zone sizes From: Greg Ungerer Message-ID: Date: Mon, 15 Jun 2020 13:53:42 +1000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: <20200412194859.12663-5-rppt@kernel.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: D28F73D663 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam01 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Hi Mike, From: Mike Rapoport > Currently, architectures that use free_area_init() to initialize memory map > and node and zone structures need to calculate zone and hole sizes. We can > use free_area_init_nodes() instead and let it detect the zone boundaries > while the architectures will only have to supply the possible limits for > the zones. > > Signed-off-by: Mike Rapoport This is causing some new warnings for me on boot on at least one non-MMU m68k target: ... NET: Registered protocol family 17 BUG: Bad page state in process swapper pfn:20165 page:41fe0ca0 refcount:0 mapcount:1 mapping:00000000 index:0x0 flags: 0x0() raw: 00000000 00000100 00000122 00000000 00000000 00000000 00000000 00000000 page dumped because: nonzero mapcount CPU: 0 PID: 1 Comm: swapper Not tainted 5.8.0-rc1-00001-g3a38f8a60c65-dirty #1 Stack from 404c9ebc: 404c9ebc 4029ab28 4029ab28 40088470 41fe0ca0 40299e21 40299df1 404ba2a4 00020165 00000000 41fd2c10 402c7ba0 41fd2c04 40088504 41fe0ca0 40299e21 00000000 40088a12 41fe0ca0 41fe0ca4 0000020a 00000000 00000001 402ca000 00000000 41fe0ca0 41fd2c10 41fd2c10 00000000 00000000 402b2388 00000001 400a0934 40091056 404c9f44 404c9f44 40088db4 402c7ba0 00000001 41fd2c04 41fe0ca0 41fd2000 41fe0ca0 40089e02 4026ecf4 40089e4e 41fe0ca0 ffffffff Call Trace: [<40088470>] 0x40088470 [<40088504>] 0x40088504 [<40088a12>] 0x40088a12 [<402ca000>] 0x402ca000 [<400a0934>] 0x400a0934 [<40091056>] 0x40091056 [<40088db4>] 0x40088db4 [<40089e02>] 0x40089e02 [<4026ecf4>] 0x4026ecf4 [<40089e4e>] 0x40089e4e [<4008ca26>] 0x4008ca26 [<4004adf8>] 0x4004adf8 [<402701ec>] 0x402701ec [<4008f25e>] 0x4008f25e [<400516f4>] 0x400516f4 [<4026eec0>] 0x4026eec0 [<400224f0>] 0x400224f0 [<402ca000>] 0x402ca000 [<4026eeda>] 0x4026eeda [<40020b00>] 0x40020b00 ... Lots more of them. ... BUG: Bad page state in process swapper pfn:201a0 page:41fe1400 refcount:0 mapcount:1 mapping:00000000 index:0x0 flags: 0x0() raw: 00000000 00000100 00000122 00000000 00000000 00000000 00000000 00000000 page dumped because: nonzero mapcount CPU: 0 PID: 1 Comm: swapper Tainted: G B 5.8.0-rc1-00001-g3a38f8a60c65-dirty #1 Stack from 404c9ebc: 404c9ebc 4029ab28 4029ab28 40088470 41fe1400 40299e21 40299df1 404ba2a4 000201a0 00000000 41fd2c10 402c7ba0 41fd2c04 40088504 41fe1400 40299e21 00000000 40088a12 41fe1400 41fe1404 0000020a 0000003b 00000001 40340000 00000000 41fe1400 41fd2c10 41fd2c10 00000000 00000000 41fe13e0 40022826 00000044 404c9f44 404c9f44 404c9f44 40088db4 402c7ba0 00000001 41fd2c04 41fe1400 41fd2000 41fe1400 40089e02 4026ecf4 40089e4e 41fe1400 ffffffff Call Trace: [<40088470>] 0x40088470 [<40088504>] 0x40088504 [<40088a12>] 0x40088a12 [<40022826>] 0x40022826 [<40088db4>] 0x40088db4 [<40089e02>] 0x40089e02 [<4026ecf4>] 0x4026ecf4 [<40089e4e>] 0x40089e4e [<4008ca26>] 0x4008ca26 [<4004adf8>] 0x4004adf8 [<402701ec>] 0x402701ec [<4008f25e>] 0x4008f25e [<400516f4>] 0x400516f4 [<4026eec0>] 0x4026eec0 [<400224f0>] 0x400224f0 [<402ca000>] 0x402ca000 [<4026eeda>] 0x4026eeda [<40020b00>] 0x40020b00 Freeing unused kernel memory: 648K This architecture does not have kernel memory protection. Run /init as init process ... System boots pretty much as normal through user space after this. Seems to be fully operational despite all those BUGONs. Specifically this is a M5208EVB target (arch/m68k/configs/m5208evb). [snip] > diff --git a/arch/m68k/mm/init.c b/arch/m68k/mm/init.c > index b88d510d4fe3..6d3147662ff2 100644 > --- a/arch/m68k/mm/init.c > +++ b/arch/m68k/mm/init.c > @@ -84,7 +84,7 @@ void __init paging_init(void) > * page_alloc get different views of the world. > */ > unsigned long end_mem = memory_end & PAGE_MASK; > - unsigned long zones_size[MAX_NR_ZONES] = { 0, }; > + unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0, }; > > high_memory = (void *) end_mem; > > @@ -98,8 +98,8 @@ void __init paging_init(void) > */ > set_fs (USER_DS); > > - zones_size[ZONE_DMA] = (end_mem - PAGE_OFFSET) >> PAGE_SHIFT; > - free_area_init(zones_size); > + max_zone_pfn[ZONE_DMA] = end_mem >> PAGE_SHIFT; > + free_area_init(max_zone_pfn); This worries me a little. On this target PAGE_OFFSET will be non-0. Thoughts? Regards Greg