From nobody Thu Nov 6 22:57:17 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1543848115399116.50922082954628; Mon, 3 Dec 2018 06:41:55 -0800 (PST) Received: from localhost ([::1]:49837 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gTpQ2-0003NY-87 for importer@patchew.org; Mon, 03 Dec 2018 09:41:54 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33798) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gTpNv-00023M-Ex for qemu-devel@nongnu.org; Mon, 03 Dec 2018 09:39:46 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gTpNu-0000iN-MP for qemu-devel@nongnu.org; Mon, 03 Dec 2018 09:39:43 -0500 Received: from mga02.intel.com ([134.134.136.20]:32862) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gTpNu-0000gE-B2 for qemu-devel@nongnu.org; Mon, 03 Dec 2018 09:39:42 -0500 Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 03 Dec 2018 06:39:41 -0800 Received: from gying1-mobl.ccr.corp.intel.com (HELO haswell-OptiPlex-9020.ccr.corp.intel.com) ([10.255.31.82]) by fmsmga005.fm.intel.com with ESMTP; 03 Dec 2018 06:39:40 -0800 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,310,1539673200"; d="scan'208";a="300567049" From: Li Zhijian To: qemu-devel@nongnu.org, mst@redhat.com, peter.maydell@linaro.org Date: Mon, 3 Dec 2018 22:48:52 +0800 Message-Id: <1543848532-12604-5-git-send-email-lizhijian@cn.fujitsu.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1543848532-12604-1-git-send-email-lizhijian@cn.fujitsu.com> References: <1543848532-12604-1-git-send-email-lizhijian@cn.fujitsu.com> X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 134.134.136.20 Subject: [Qemu-devel] [PATCH for-4.0 v3 4/4] i386: allow to load initrd below 4G for recent linux X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eduardo Habkost , Li Zhijian , philip.li@intel.com, zhijianx.li@intel.com, Paolo Bonzini , Richard Henderson Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" a new field xloadflags was added to recent x86 linux, and BIT 1: XLF_CAN_BE_LOADED_ABOVE_4G is used to tell bootload that where initrd can be loaded safely. Current QEMU/BIOS always loads initrd below below_4g_mem_size which is alwa= ys less than 4G, so here limiting initrd_max to 4G - 1 simply is enough if this bit is set. CC: Paolo Bonzini CC: Richard Henderson CC: Eduardo Habkost CC: "Michael S. Tsirkin" CC: Marcel Apfelbaum Signed-off-by: Li Zhijian --- V3: correct grammar and check XLF_CAN_BE_LOADED_ABOVE_4G first (Michael S. = Tsirkin) Signed-off-by: Li Zhijian --- hw/i386/pc.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/hw/i386/pc.c b/hw/i386/pc.c index 8db7417..ebaa65f 100644 --- a/hw/i386/pc.c +++ b/hw/i386/pc.c @@ -897,7 +897,15 @@ static void load_linux(PCMachineState *pcms, #endif =20 /* highest address for loading the initrd */ - if (protocol >=3D 0x203) { + if (protocol >=3D 0x20c && + lduw_p(header+0x236) & XLF_CAN_BE_LOADED_ABOVE_4G) { + /* + * Although kernel allows initrd loading to above 4G, + * it just makes it as large as possible while still staying below= 4G + * since current BIOS always loads initrd below pcms->below_4g_mem= _size + */ + initrd_max =3D UINT32_MAX; + } else if (protocol >=3D 0x203) { initrd_max =3D ldl_p(header+0x22c); } else { initrd_max =3D 0x37ffffff; --=20 2.7.4