From patchwork Wed Jul 29 03:34:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jia He X-Patchwork-Id: 11690295 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 C5B3A1575 for ; Wed, 29 Jul 2020 03:36:02 +0000 (UTC) Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id A9C6E2075F for ; Wed, 29 Jul 2020 03:36:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A9C6E2075F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nvdimm-bounces@lists.01.org Received: from ml01.vlan13.01.org (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id A347112693ECE; Tue, 28 Jul 2020 20:36:02 -0700 (PDT) Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=217.140.110.172; helo=foss.arm.com; envelope-from=justin.he@arm.com; receiver= Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by ml01.01.org (Postfix) with ESMTP id AB1C712664311 for ; Tue, 28 Jul 2020 20:36:00 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 14AB831B; Tue, 28 Jul 2020 20:36:00 -0700 (PDT) Received: from localhost.localdomain (entos-thunderx2-02.shanghai.arm.com [10.169.212.213]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 8D9883F66E; Tue, 28 Jul 2020 20:35:52 -0700 (PDT) From: Jia He To: Dan Williams , Vishal Verma , Mike Rapoport , David Hildenbrand Subject: [RFC PATCH 6/6] arm64: fall back to vmemmap_populate_basepages if not aligned with PMD_SIZE Date: Wed, 29 Jul 2020 11:34:24 +0800 Message-Id: <20200729033424.2629-7-justin.he@arm.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200729033424.2629-1-justin.he@arm.com> References: <20200729033424.2629-1-justin.he@arm.com> Message-ID-Hash: M6W4VTZYOE7GTXSK4S5COXA6S74EG24S X-Message-ID-Hash: M6W4VTZYOE7GTXSK4S5COXA6S74EG24S X-MailFrom: justin.he@arm.com X-Mailman-Rule-Hits: nonmember-moderation X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation CC: Catalin Marinas , Will Deacon , Greg Kroah-Hartman , "Rafael J. Wysocki" , Andrew Morton , Steve Capper , Mark Rutland , Anshuman Khandual , Hsin-Yi Wang , Jason Gunthorpe , Dave Hansen , Kees Cook , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-nvdimm@lists.01.org, linux-mm@kvack.org, Pankaj Gupta , Kaly Xin , Jia He X-Mailman-Version: 3.1.1 Precedence: list List-Id: "Linux-nvdimm developer list." Archived-At: List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In dax pmem kmem (dax pmem used as RAM device) case, the start address might not be aligned with PMD_SIZE e.g. 240000000-33fdfffff : Persistent Memory 240000000-2421fffff : namespace0.0 242400000-2bfffffff : dax0.0 242400000-2bfffffff : System RAM (kmem) pfn_to_page(0x242400000) is fffffe0007e90000. Without this patch, vmemmap_populate(fffffe0007e90000, ...) will incorrectly create a pmd mapping [fffffe0007e00000, fffffe0008000000] which contains fffffe0007e90000. This adds the check and then falls back to vmemmap_populate_basepages() Signed-off-by: Jia He --- arch/arm64/mm/mmu.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index d69feb2cfb84..3b21bd47e801 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -1102,6 +1102,10 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, do { next = pmd_addr_end(addr, end); + if (next - addr < PMD_SIZE) { + vmemmap_populate_basepages(start, next, node, altmap); + continue; + } pgdp = vmemmap_pgd_populate(addr, node); if (!pgdp)