From patchwork Mon Feb 10 00:50:48 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wei Yang X-Patchwork-Id: 11372359 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id CD1D414B4 for ; Mon, 10 Feb 2020 00:50:46 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 8DF4620733 for ; Mon, 10 Feb 2020 00:50:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8DF4620733 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id BCC8B6B0080; Sun, 9 Feb 2020 19:50:45 -0500 (EST) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id B7CA16B0081; Sun, 9 Feb 2020 19:50:45 -0500 (EST) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A92BE6B0082; Sun, 9 Feb 2020 19:50:45 -0500 (EST) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0156.hostedemail.com [216.40.44.156]) by kanga.kvack.org (Postfix) with ESMTP id 8E1A16B0080 for ; Sun, 9 Feb 2020 19:50:45 -0500 (EST) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 4608E2C93 for ; Mon, 10 Feb 2020 00:50:45 +0000 (UTC) X-FDA: 76472387250.28.burn49_7ae96f280c852 X-Spam-Summary: 1,0,0,,d41d8cd98f00b204,richardw.yang@linux.intel.com,:akpm@linux-foundation.org:osalvador@suse.de:dan.j.williams@intel.com::linux-kernel@vger.kernel.org:richardw.yang@linux.intel.com:david@redhat.com:bhe@redhat.com,RULES_HIT:30003:30054:30064,0,RBL:192.55.52.115:@linux.intel.com:.lbl8.mailshell.net-62.18.0.100 64.95.201.95,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fn,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:26,LUA_SUMMARY:none X-HE-Tag: burn49_7ae96f280c852 X-Filterd-Recvd-Size: 2458 Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by imf30.hostedemail.com (Postfix) with ESMTP for ; Mon, 10 Feb 2020 00:50:44 +0000 (UTC) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 09 Feb 2020 16:50:43 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,423,1574150400"; d="scan'208";a="405427008" Received: from richard.sh.intel.com (HELO localhost) ([10.239.159.54]) by orsmga005.jf.intel.com with ESMTP; 09 Feb 2020 16:50:41 -0800 From: Wei Yang To: akpm@linux-foundation.org, osalvador@suse.de, dan.j.williams@intel.com Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Wei Yang , David Hildenbrand , Baoquan He Subject: [Patch v2] mm/sparsemem: get address to page struct instead of address to pfn Date: Mon, 10 Feb 2020 08:50:48 +0800 Message-Id: <20200210005048.10437-1-richardw.yang@linux.intel.com> X-Mailer: git-send-email 2.17.1 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: memmap should be the address to page struct instead of address to pfn. As mentioned by David, if system memory and devmem sit within a section, the mismatch address would lead kdump to dump unexpected memory. Since sub-section only works for SPARSEMEM_VMEMMAP, pfn_to_page() is valid to get the page struct address at this point. Fixes: ba72b4c8cf60 ("mm/sparsemem: support sub-section hotplug") Signed-off-by: Wei Yang CC: Dan Williams CC: David Hildenbrand CC: Baoquan He Acked-by: David Hildenbrand --- v2: * adjust comment to mention the mismatch data would affect kdump --- mm/sparse.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/sparse.c b/mm/sparse.c index 586d85662978..4862ec2cfbc0 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -887,7 +887,7 @@ int __meminit sparse_add_section(int nid, unsigned long start_pfn, /* Align memmap to section boundary in the subsection case */ if (section_nr_to_pfn(section_nr) != start_pfn) - memmap = pfn_to_kaddr(section_nr_to_pfn(section_nr)); + memmap = pfn_to_page(section_nr_to_pfn(section_nr)); sparse_init_one_section(ms, section_nr, memmap, ms->usage, 0); return 0;