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=-3.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 2FDF9C31E49 for ; Sun, 16 Jun 2019 03:50:21 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 8BB5D2084D for ; Sun, 16 Jun 2019 03:50:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8BB5D2084D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id EEDA66B0005; Sat, 15 Jun 2019 23:50:18 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E9FA76B0006; Sat, 15 Jun 2019 23:50:18 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D8F168E0001; Sat, 15 Jun 2019 23:50:18 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from mail-yb1-f198.google.com (mail-yb1-f198.google.com [209.85.219.198]) by kanga.kvack.org (Postfix) with ESMTP id B861E6B0005 for ; Sat, 15 Jun 2019 23:50:18 -0400 (EDT) Received: by mail-yb1-f198.google.com with SMTP id u3so7489809ybu.7 for ; Sat, 15 Jun 2019 20:50:18 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-original-authentication-results:x-gm-message-state:from:to:cc :subject:in-reply-to:references:date:mime-version:message-id; bh=8tzI7/Jx0Nps2iURLacuN0RtP13PIB8dpM6hJJgr1Ao=; b=t7HsTDvXHEJ/k8plXwbcIipebAdflTYwEe//2gkm+WagLXgfB8PYHyYHva8c0VjNot 6CpaDE34R6lbY+lCcAXpvBDFpuCGyuDPrvAU/VBRhDL5YVJ1ic5I3qg8u940ZxwO5i72 FkSaTtDc+C5jR68g2XimvO5POxOMxqFhjnHjyGIqIWBSC5G/tIWpCe2TNe8qDZW3nhXL i5mon3bvNPy7E1Vq7gp/V9olVxKqN4t/sHNFx4e9UsA9Zdfrt5Y4PXW+GEaFzCVeN1k7 H+0Q1Zg4J8iT9sn5MM6nHkBMsHZ+5t8MR3KLDQsgEeK4hd78Tj9HZfLUeAQ9dKILesK4 kdOg== X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of aneesh.kumar@linux.ibm.com designates 148.163.158.5 as permitted sender) smtp.mailfrom=aneesh.kumar@linux.ibm.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=ibm.com X-Gm-Message-State: APjAAAXqF8/Jx8ED2wwopTwSvSzKw48jYnpWgVfkDS7tPRsHBGjbA8g/ dbdOWObKUwOSkdypfzds/F7FFTidDA+x9AwJAqcxpnVGk4ds3i/JcPmUpN4rRFuf71hTHVFKczO L4cVazxkkPr4P4FuhyYbGRKXWYDsP8LneLjXgbofEHDbdiYwUvolxA93LJmm43aMSuQ== X-Received: by 2002:a81:d20b:: with SMTP id x11mr46422848ywi.47.1560657018412; Sat, 15 Jun 2019 20:50:18 -0700 (PDT) X-Google-Smtp-Source: APXvYqxr6u+vp+UURy7EGCBLt5Rstordl+7krcIdPRWpbQc92ANpODY0gmFyXflZUAJKoWpQFfOC X-Received: by 2002:a81:d20b:: with SMTP id x11mr46422825ywi.47.1560657017613; Sat, 15 Jun 2019 20:50:17 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1560657017; cv=none; d=google.com; s=arc-20160816; b=vyJ7FmMiJEz/T08BQ+DjBksZHxPVIf2Ji0vm3o93AXBg4qgQdE7BRSbXCj5pt8pofK 0r51jkNvc0tDBb4RONClLV5LyucW+RUezMkm7o2scvQsxESLVKH7UUdBhQz8dTZvhrVJ p2S6ffhNXnLZ6AybVKoHTuO6Qlv51gSzL7oJ603ULF51KQFThGedujd7BSuG6k+YAd2f mf9rlnYTH9FileCTsMPRFNW0dKTpw0IcTPwnOw409A/w1Q2iy/Npk/wytKWEsmlpCJlN /TOq8OF2zMl9Xuod/YXbto5Dl9Hl85dlaJelEtDGDMEKkfF3XWYpMnv6mFlBx41qugUj EwlQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=message-id:mime-version:date:references:in-reply-to:subject:cc:to :from; bh=8tzI7/Jx0Nps2iURLacuN0RtP13PIB8dpM6hJJgr1Ao=; b=z7wFyDJ2iuQ7r9x/C+AYd1mgAqzaRVD7BScvWEgsJlCNNOfhHrZDB4wCdyLAufvHqh nHrGD6lbn5BWf3UW+t5KBBDlyGltP5OmPa+Ob2HycFU6wqGKgPbVKf0VNtrNb0Jb83oB HrxvVJ0fcwutXMNILH/UfRTkcyeW8mEjiO1W5QU0qxZGdavM/ojw/56HK1KXccTJVk4q rDRjmoMukBXilfegyFSNZBRMKTwEeNo9Fz+Qj07Hs9ZwZqa2NZVydnFXOqXui0LRQY8O osWsb0DxpFLuUFxn5c985wZzdczKrpBiaMrRH4ggUk9UhGTyyhPLtdWndzgv+1Wvj5w0 jrDQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of aneesh.kumar@linux.ibm.com designates 148.163.158.5 as permitted sender) smtp.mailfrom=aneesh.kumar@linux.ibm.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=ibm.com Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com. [148.163.158.5]) by mx.google.com with ESMTPS id f125si2760188ywb.145.2019.06.15.20.50.17 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 15 Jun 2019 20:50:17 -0700 (PDT) Received-SPF: pass (google.com: domain of aneesh.kumar@linux.ibm.com designates 148.163.158.5 as permitted sender) client-ip=148.163.158.5; Authentication-Results: mx.google.com; spf=pass (google.com: domain of aneesh.kumar@linux.ibm.com designates 148.163.158.5 as permitted sender) smtp.mailfrom=aneesh.kumar@linux.ibm.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=ibm.com Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x5G3lMQI125045 for ; Sat, 15 Jun 2019 23:50:17 -0400 Received: from e06smtp04.uk.ibm.com (e06smtp04.uk.ibm.com [195.75.94.100]) by mx0b-001b2d01.pphosted.com with ESMTP id 2t5dwx8ece-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Sat, 15 Jun 2019 23:50:16 -0400 Received: from localhost by e06smtp04.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Sun, 16 Jun 2019 04:50:15 +0100 Received: from b06cxnps4076.portsmouth.uk.ibm.com (9.149.109.198) by e06smtp04.uk.ibm.com (192.168.101.134) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Sun, 16 Jun 2019 04:50:12 +0100 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06cxnps4076.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x5G3oBUR49348710 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Sun, 16 Jun 2019 03:50:11 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 51C71AE057; Sun, 16 Jun 2019 03:50:11 +0000 (GMT) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 8981FAE04D; Sun, 16 Jun 2019 03:50:09 +0000 (GMT) Received: from skywalker.linux.ibm.com (unknown [9.85.86.48]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTP; Sun, 16 Jun 2019 03:50:09 +0000 (GMT) X-Mailer: emacs 26.2 (via feedmail 11-beta-1 I) From: "Aneesh Kumar K.V" To: Dan Williams Cc: Oscar Salvador , Qian Cai , Andrew Morton , Linux MM , Linux Kernel Mailing List , jmoyer Subject: Re: [PATCH -next] mm/hotplug: skip bad PFNs from pfn_to_online_page() In-Reply-To: References: <1560366952-10660-1-git-send-email-cai@lca.pw> <1560376072.5154.6.camel@lca.pw> <87lfy4ilvj.fsf@linux.ibm.com> <20190614153535.GA9900@linux> Date: Sun, 16 Jun 2019 09:19:42 +0530 MIME-Version: 1.0 Content-Type: text/plain X-TM-AS-GCONF: 00 x-cbid: 19061603-0016-0000-0000-000002897078 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19061603-0017-0000-0000-000032E6B591 Message-Id: <87imt6i3zd.fsf@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-06-16_02:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=27 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1906160035 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: Dan Williams writes: > On Fri, Jun 14, 2019 at 9:18 AM Aneesh Kumar K.V > wrote: >> >> On 6/14/19 9:05 PM, Oscar Salvador wrote: >> > On Fri, Jun 14, 2019 at 02:28:40PM +0530, Aneesh Kumar K.V wrote: >> >> Can you check with this change on ppc64. I haven't reviewed this series yet. >> >> I did limited testing with change . Before merging this I need to go >> >> through the full series again. The vmemmap poplulate on ppc64 needs to >> >> handle two translation mode (hash and radix). With respect to vmemap >> >> hash doesn't setup a translation in the linux page table. Hence we need >> >> to make sure we don't try to setup a mapping for a range which is >> >> arleady convered by an existing mapping. >> >> >> >> diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c >> >> index a4e17a979e45..15c342f0a543 100644 >> >> --- a/arch/powerpc/mm/init_64.c >> >> +++ b/arch/powerpc/mm/init_64.c >> >> @@ -88,16 +88,23 @@ static unsigned long __meminit vmemmap_section_start(unsigned long page) >> >> * which overlaps this vmemmap page is initialised then this page is >> >> * initialised already. >> >> */ >> >> -static int __meminit vmemmap_populated(unsigned long start, int page_size) >> >> +static bool __meminit vmemmap_populated(unsigned long start, int page_size) >> >> { >> >> unsigned long end = start + page_size; >> >> start = (unsigned long)(pfn_to_page(vmemmap_section_start(start))); >> >> >> >> - for (; start < end; start += (PAGES_PER_SECTION * sizeof(struct page))) >> >> - if (pfn_valid(page_to_pfn((struct page *)start))) >> >> - return 1; >> >> + for (; start < end; start += (PAGES_PER_SECTION * sizeof(struct page))) { >> >> >> >> - return 0; >> >> + struct mem_section *ms; >> >> + unsigned long pfn = page_to_pfn((struct page *)start); >> >> + >> >> + if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS) >> >> + return 0; >> > >> > I might be missing something, but is this right? >> > Having a section_nr above NR_MEM_SECTIONS is invalid, but if we return 0 here, >> > vmemmap_populate will go on and populate it. >> >> I should drop that completely. We should not hit that condition at all. >> I will send a final patch once I go through the full patch series making >> sure we are not breaking any ppc64 details. >> >> Wondering why we did the below >> >> #if defined(ARCH_SUBSECTION_SHIFT) >> #define SUBSECTION_SHIFT (ARCH_SUBSECTION_SHIFT) >> #elif defined(PMD_SHIFT) >> #define SUBSECTION_SHIFT (PMD_SHIFT) >> #else >> /* >> * Memory hotplug enabled platforms avoid this default because they >> * either define ARCH_SUBSECTION_SHIFT, or PMD_SHIFT is a constant, but >> * this is kept as a backstop to allow compilation on >> * !ARCH_ENABLE_MEMORY_HOTPLUG archs. >> */ >> #define SUBSECTION_SHIFT 21 >> #endif >> >> why not >> >> #if defined(ARCH_SUBSECTION_SHIFT) >> #define SUBSECTION_SHIFT (ARCH_SUBSECTION_SHIFT) >> #else >> #define SUBSECTION_SHIFT SECTION_SHIFT >> #endif >> >> ie, if SUBSECTION is not supported by arch we have one sub-section per >> section? > > A couple comments: > > The only reason ARCH_SUBSECTION_SHIFT exists is because PMD_SHIFT on > PowerPC was a non-constant value. However, I'm planning to remove the > distinction in the next rev of the patches. Jeff rightly points out > that having a variable subsection size per arch will lead to > situations where persistent memory namespaces are not portable across > archs. So I plan to just make SUBSECTION_SHIFT 21 everywhere. What is the dependency between subsection and pageblock_order? Shouldn't subsection size >= pageblock size? We do have pageblock size drived from HugeTLB size. -aneesh