From patchwork Thu Mar 30 11:49:51 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kirill A. Shutemov" X-Patchwork-Id: 669277 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 22B99C77B6D for ; Thu, 30 Mar 2023 11:50:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231144AbjC3Luc (ORCPT ); Thu, 30 Mar 2023 07:50:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43530 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231159AbjC3Lu1 (ORCPT ); Thu, 30 Mar 2023 07:50:27 -0400 Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 36BE2A24B; Thu, 30 Mar 2023 04:50:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1680177026; x=1711713026; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=f7/hrgLyEe7uCgqzPwQBAiXJTS6cTMMnuaKLYQlQP9E=; b=G3v8P3ru+eaQYI7MqNa9vb+Hy499tRdtoMOlKZq9wzcolQVJpqIHwEgb LaH0yrgdJTc3rbq+tzAm0G3G8KhCWNrPxmGk9y3HrsCamrqtyFGw3sOMH +qOa3/Xj8miI5t18P6nXLhoDnStt6l7bu/UiuEF6+Dmpare1Hj0ws11VH CGcIGibNfP5jJCGriwGOdIH/MlBzpnicwRMo6Li15/PlR/BQh3WgP3PWd NcKFglfpg5MvfcLUtQ2hkyMxK5RZVJEYY1y48MOpTb3NNSWR/4E54m53v sp9lNV0qRbFbnIfERimIFYTbOLovQVCB/qr62l2PoODEL68EkUmmewYOk A==; X-IronPort-AV: E=McAfee;i="6600,9927,10664"; a="339868489" X-IronPort-AV: E=Sophos;i="5.98,303,1673942400"; d="scan'208";a="339868489" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Mar 2023 04:50:24 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10664"; a="1014401448" X-IronPort-AV: E=Sophos;i="5.98,303,1673942400"; d="scan'208";a="1014401448" Received: from ngreburx-mobl.ger.corp.intel.com (HELO box.shutemov.name) ([10.251.209.91]) by fmsmga005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Mar 2023 04:50:17 -0700 Received: by box.shutemov.name (Postfix, from userid 1000) id 49CA4104545; Thu, 30 Mar 2023 14:50:00 +0300 (+03) 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 , Dario Faggioli , Dave Hansen , Mike Rapoport , David Hildenbrand , Mel Gorman , marcelo.cerri@canonical.com, tim.gardner@canonical.com, khalid.elmously@canonical.com, philip.cox@canonical.com, aarcange@redhat.com, peterx@redhat.com, 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" , Mike Rapoport Subject: [PATCHv9 09/14] x86/mm: Reserve unaccepted memory bitmap Date: Thu, 30 Mar 2023 14:49:51 +0300 Message-Id: <20230330114956.20342-10-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230330114956.20342-1-kirill.shutemov@linux.intel.com> References: <20230330114956.20342-1-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org A given page of memory can only be accepted once. The kernel has to accept memory both in the early decompression stage and during normal runtime. A bitmap is used to communicate the acceptance state of each page between the decompression stage and normal runtime. boot_params is used to communicate location of the bitmap throughout the boot. The bitmap is allocated and initially populated in EFI stub. Decompression stage accepts pages required for kernel/initrd and marks these pages accordingly in the bitmap. The main kernel picks up the bitmap from the same boot_params and uses it to determine what has to be accepted on allocation. In the runtime kernel, reserve the bitmap's memory to ensure nothing overwrites it. The size of bitmap is determined with e820__end_of_ram_pfn() which relies on setup_e820() marking unaccepted memory as E820_TYPE_RAM. Signed-off-by: Kirill A. Shutemov Acked-by: Mike Rapoport --- arch/x86/kernel/e820.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c index fb8cf953380d..483c36a28d2e 100644 --- a/arch/x86/kernel/e820.c +++ b/arch/x86/kernel/e820.c @@ -1316,6 +1316,23 @@ void __init e820__memblock_setup(void) int i; u64 end; + /* + * Mark unaccepted memory bitmap reserved. + * + * This kind of reservation usually done from early_reserve_memory(), + * but early_reserve_memory() called before e820__memory_setup(), so + * e820_table is not finalized and e820__end_of_ram_pfn() cannot be + * used to get correct RAM size. + */ + if (boot_params.unaccepted_memory) { + unsigned long size; + + /* One bit per 2MB */ + size = 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