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]) by smtp.lore.kernel.org (Postfix) with ESMTP id D2A48C433FE for ; Fri, 28 Jan 2022 20:59:19 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 3E3C86B0106; Fri, 28 Jan 2022 15:59:17 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 344336B0108; Fri, 28 Jan 2022 15:59:17 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1BDCD6B0109; Fri, 28 Jan 2022 15:59:17 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0131.hostedemail.com [216.40.44.131]) by kanga.kvack.org (Postfix) with ESMTP id 0CE106B0106 for ; Fri, 28 Jan 2022 15:59:17 -0500 (EST) Received: from smtpin30.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id BB187812A49A for ; Fri, 28 Jan 2022 20:59:16 +0000 (UTC) X-FDA: 79080911112.30.9E5F638 Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by imf01.hostedemail.com (Postfix) with ESMTP id EFF5E40031 for ; Fri, 28 Jan 2022 20:59:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1643403556; x=1674939556; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=koK/VhFGViq6NfT00njMUR21vAbvfWnplJSVKWqjHls=; b=da0xSoiX43YVdlnSINNE6uF/velbbvAj6p04olflQ01+4cCZA2CdNSjl fLB5H47FBpEZlph3bTDDNhdsBFDtluqwWBpk4hYL9jY9BsBK2UOXmVPlx a0lvMBjxvZczSdbj5acIEqWZmVzYcXLqtB9kwOzqoID99WHU3Rh1+hGR0 dL82pRu/qq+OCqf+UuwFI2cnP+/Ln/oAQzLokUkb2iwy4cr5wbGiCfg86 9goEyutwW8l7j4Z6L1YhPnSydUetwj7SgRv8eATveh8FMQh+UHTKsd2lA +HNdtdRNCi/hSCFeuzQ40R2T/0/GRWOxN+n6o67MzQg6tYPim01fuzVZz w==; X-IronPort-AV: E=McAfee;i="6200,9189,10241"; a="227865751" X-IronPort-AV: E=Sophos;i="5.88,324,1635231600"; d="scan'208";a="227865751" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Jan 2022 12:59:11 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.88,324,1635231600"; d="scan'208";a="533622715" Received: from black.fi.intel.com ([10.237.72.28]) by fmsmga007.fm.intel.com with ESMTP; 28 Jan 2022 12:59:03 -0800 Received: by black.fi.intel.com (Postfix, from userid 1000) id C5335477; Fri, 28 Jan 2022 22:59:09 +0200 (EET) From: "Kirill A. Shutemov" To: Borislav Petkov , Andy Lutomirski , Sean Christopherson , Andrew Morton , Joerg Roedel , Ard Biesheuvel Cc: Andi Kleen , Kuppuswamy Sathyanarayanan , David Rientjes , Vlastimil Babka , Tom Lendacky , Thomas Gleixner , Peter Zijlstra , Paolo Bonzini , Ingo Molnar , Varad Gautam , Dario Faggioli , Dave Hansen , Brijesh Singh , Mike Rapoport , David Hildenbrand , x86@kernel.org, linux-mm@kvack.org, linux-coco@lists.linux.dev, linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" Subject: [PATCHv3 5/7] x86/mm: Reserve unaccepted memory bitmap Date: Fri, 28 Jan 2022 23:59:04 +0300 Message-Id: <20220128205906.27503-6-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220128205906.27503-1-kirill.shutemov@linux.intel.com> References: <20220128205906.27503-1-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 X-Rspam-User: nil X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: EFF5E40031 X-Stat-Signature: d8ax6j5uwb9yw5fkqq9nw1t1xrtj9nty Authentication-Results: imf01.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=da0xSoiX; dmarc=pass (policy=none) header.from=intel.com; spf=none (imf01.hostedemail.com: domain of kirill.shutemov@linux.intel.com has no SPF policy when checking 192.55.52.151) smtp.mailfrom=kirill.shutemov@linux.intel.com X-HE-Tag: 1643403555-434127 Content-Transfer-Encoding: quoted-printable 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: A given page of memory can only be accepted once. The kernel has a need to accept memory both in the early decompression stage and during normal runtime. Use a bitmap to communicate the acceptance state of each page between the decompression stage and normal runtime. This eliminates the possibility of attempting to double-accept a page. Allocate the bitmap during decompression stage and hand it over to the main kernel image via boot_params. In the runtime kernel, reserve the bitmap's memory to ensure nothing overwrites it. Signed-off-by: Kirill A. Shutemov --- arch/x86/kernel/e820.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c index bc0657f0deed..3905bd1ca41d 100644 --- a/arch/x86/kernel/e820.c +++ b/arch/x86/kernel/e820.c @@ -1297,6 +1297,16 @@ void __init e820__memblock_setup(void) int i; u64 end; =20 + /* Mark unaccepted memory bitmap reserved */ + if (boot_params.unaccepted_memory) { + unsigned long size; + + /* One bit per 2MB */ + size =3D DIV_ROUND_UP(e820__end_of_ram_pfn() * PAGE_SIZE, + PMD_SIZE * BITS_PER_BYTE); + memblock_reserve(boot_params.unaccepted_memory, size); + } + /* * The bootstrap memblock region count maximum is 128 entries * (INIT_MEMBLOCK_REGIONS), but EFI might pass us more E820 entries --=20 2.34.1