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 EBBBCC433FE for ; Sun, 30 Jan 2022 16:48:24 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 28ADE6B0072; Sun, 30 Jan 2022 11:48:24 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 23ABB6B0073; Sun, 30 Jan 2022 11:48:24 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 101D96B0074; Sun, 30 Jan 2022 11:48:24 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0206.hostedemail.com [216.40.44.206]) by kanga.kvack.org (Postfix) with ESMTP id F25A76B0072 for ; Sun, 30 Jan 2022 11:48:23 -0500 (EST) Received: from smtpin07.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id AC8E995CB2 for ; Sun, 30 Jan 2022 16:48:23 +0000 (UTC) X-FDA: 79087536486.07.30BA6AD Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by imf23.hostedemail.com (Postfix) with ESMTP id C5F1D140005 for ; Sun, 30 Jan 2022 16:48:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1643561302; x=1675097302; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=nSSz3PwT9pAlklbcpqd0bHWy9ItvvFudWk2pwJNvLyg=; b=dxX9jwd8INQ+Rg/+HZRaoKupL2nNRJ1ljfE7lv/wHYDP60IcAZ4C7lPS aOsLYFG9ofAlUCvroXY//kDF0cNUI25sNTpsycBRDuBWCFbHJ3MHHzLOd Jfa9uHUDZ1tJOArRX1zjDnWqJtv9MdnPmWig78odBdMbF8hPJBwkbeuyQ r20UxozRYxgxHkqY0OpUP6QuHc2BLJHbnTrhotucVmJBMxZ+cqyLSyms7 TA1kh831aaNK7F7gXkj7w4koRlCht0amouQPeRSd4lMNzDM3AHCkxOY3Z U7+70EY+2/lhRpvT+9zm8BUifpulD7l/DRxoHMtwH72z9BZYxtkLPl/wj w==; X-IronPort-AV: E=McAfee;i="6200,9189,10242"; a="234750725" X-IronPort-AV: E=Sophos;i="5.88,329,1635231600"; d="scan'208";a="234750725" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Jan 2022 08:48:21 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.88,329,1635231600"; d="scan'208";a="629634558" Received: from black.fi.intel.com ([10.237.72.28]) by orsmga004.jf.intel.com with ESMTP; 30 Jan 2022 08:48:14 -0800 Received: by black.fi.intel.com (Postfix, from userid 1000) id 83CFC176; Sun, 30 Jan 2022 18:48:28 +0200 (EET) From: "Kirill A. Shutemov" To: rppt@kernel.org Cc: ak@linux.intel.com, akpm@linux-foundation.org, ardb@kernel.org, bp@alien8.de, brijesh.singh@amd.com, dave.hansen@intel.com, david@redhat.com, dfaggioli@suse.com, jroedel@suse.de, kirill.shutemov@linux.intel.com, linux-coco@lists.linux.dev, linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, luto@kernel.org, mingo@redhat.com, pbonzini@redhat.com, peterz@infradead.org, rientjes@google.com, sathyanarayanan.kuppuswamy@linux.intel.com, seanjc@google.com, tglx@linutronix.de, thomas.lendacky@amd.com, varad.gautam@suse.com, vbabka@suse.cz, x86@kernel.org, Mike Rapoport Subject: [PATCHv3.1 5/7] x86/mm: Reserve unaccepted memory bitmap Date: Sun, 30 Jan 2022 19:48:23 +0300 Message-Id: <20220130164823.40470-1-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: References: MIME-Version: 1.0 X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: C5F1D140005 X-Stat-Signature: s4pa93juxima1894g4tm4sk4arrbcd6x X-Rspam-User: nil Authentication-Results: imf23.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=dxX9jwd8; spf=none (imf23.hostedemail.com: domain of kirill.shutemov@linux.intel.com has no SPF policy when checking 134.134.136.20) smtp.mailfrom=kirill.shutemov@linux.intel.com; dmarc=pass (policy=none) header.from=intel.com X-HE-Tag: 1643561302-579304 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. A bitmap used to communicate the acceptance state of each page between th= e decompression stage and normal runtime. This eliminates the possibility = of attempting to double-accept a page. The bitmap is allocated in EFI stub, decompression stage updates the stat= e of pages used for the kernel and initrd and hands the bitmap 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 Acked-by: Mike Rapoport --- 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