From patchwork Tue Jan 4 08:32:30 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Kiszka X-Patchwork-Id: 77424 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [199.232.76.165]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id CF96AB70A3 for ; Tue, 4 Jan 2011 20:03:08 +1100 (EST) Received: from localhost ([127.0.0.1]:36902 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Pa2nD-0000S5-L9 for incoming@patchwork.ozlabs.org; Tue, 04 Jan 2011 04:02:59 -0500 Received: from [140.186.70.92] (port=55846 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Pa2K3-00016o-6x for qemu-devel@nongnu.org; Tue, 04 Jan 2011 03:32:54 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Pa2Jx-0004g3-9T for qemu-devel@nongnu.org; Tue, 04 Jan 2011 03:32:51 -0500 Received: from fmmailgate03.web.de ([217.72.192.234]:37502) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Pa2Jw-0004fK-RI for qemu-devel@nongnu.org; Tue, 04 Jan 2011 03:32:45 -0500 Received: from smtp04.web.de ( [172.20.0.225]) by fmmailgate03.web.de (Postfix) with ESMTP id 2999118392933; Tue, 4 Jan 2011 09:32:44 +0100 (CET) Received: from [88.64.22.98] (helo=localhost.localdomain) by smtp04.web.de with asmtp (TLSv1:AES256-SHA:256) (WEB.DE 4.110 #2) id 1Pa2Jw-00050n-00; Tue, 04 Jan 2011 09:32:44 +0100 From: Jan Kiszka To: Avi Kivity , Marcelo Tosatti Date: Tue, 4 Jan 2011 09:32:30 +0100 Message-Id: <2efcebfac8252a2ee8908890519f88684626f9ad.1294129949.git.jan.kiszka@web.de> X-Mailer: git-send-email 1.7.1 In-Reply-To: References: In-Reply-To: References: X-Sender: jan.kiszka@web.de X-Provags-ID: V01U2FsdGVkX189cdXkPgcLndZ2ORm6UiDKGcs3kI34RyG9jWl0 6OXPJfkzicCuiYPuJSHzhRX0q337ghkeftN4h7UErxSDGvYDSQ obbKNLrbE= X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.4-2.6 Cc: qemu-devel@nongnu.org, kvm@vger.kernel.org Subject: [Qemu-devel] [PATCH v3 18/21] kvm: x86: Rework identity map and TSS setup for larger BIOS sizes X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org From: Jan Kiszka In order to support loading BIOSes > 256K, reorder the code, adjusting the base if the kernel supports moving the identity map. Signed-off-by: Jan Kiszka --- target-i386/kvm.c | 63 +++++++++++++++++++++++++--------------------------- 1 files changed, 30 insertions(+), 33 deletions(-) diff --git a/target-i386/kvm.c b/target-i386/kvm.c index 58122d9..50d8ec8 100644 --- a/target-i386/kvm.c +++ b/target-i386/kvm.c @@ -578,27 +578,9 @@ static int kvm_get_supported_msrs(void) return ret; } -static int kvm_init_identity_map_page(void) -{ -#ifdef KVM_CAP_SET_IDENTITY_MAP_ADDR - int ret; - uint64_t addr = 0xfffbc000; - - if (!kvm_check_extension(KVM_CAP_SET_IDENTITY_MAP_ADDR)) { - return 0; - } - - ret = kvm_vm_ioctl(KVM_SET_IDENTITY_MAP_ADDR, &addr); - if (ret < 0) { - fprintf(stderr, "kvm_set_identity_map_addr: %s\n", strerror(ret)); - return ret; - } -#endif - return 0; -} - int kvm_arch_init(void) { + uint64_t identity_base = 0xfffbc000; int ret; struct utsname utsname; @@ -614,27 +596,42 @@ int kvm_arch_init(void) uname(&utsname); lm_capable_kernel = strcmp(utsname.machine, "x86_64") == 0; - /* create vm86 tss. KVM uses vm86 mode to emulate 16-bit code - * directly. In order to use vm86 mode, a TSS is needed. Since this - * must be part of guest physical memory, we need to allocate it. */ - - /* this address is 3 pages before the bios, and the bios should present - * as unavaible memory. FIXME, need to ensure the e820 map deals with - * this? - */ /* - * Tell fw_cfg to notify the BIOS to reserve the range. + * On older Intel CPUs, KVM uses vm86 mode to emulate 16-bit code directly. + * In order to use vm86 mode, an EPT identity map and a TSS are needed. + * Since these must be part of guest physical memory, we need to allocate + * them, both by setting their start addresses in the kernel and by + * creating a corresponding e820 entry. We need 4 pages before the BIOS. + * + * Older KVM versions may not support setting the identity map base. In + * that case we need to stick with the default, i.e. a 256K maximum BIOS + * size. */ - if (e820_add_entry(0xfffbc000, 0x4000, E820_RESERVED) < 0) { - perror("e820_add_entry() table is full"); - exit(1); +#ifdef KVM_CAP_SET_IDENTITY_MAP_ADDR + if (kvm_check_extension(KVM_CAP_SET_IDENTITY_MAP_ADDR)) { + /* Allows up to 16M BIOSes. */ + identity_base = 0xfeffc000; + + ret = kvm_vm_ioctl(KVM_SET_IDENTITY_MAP_ADDR, &identity_base); + if (ret < 0) { + return ret; + } } - ret = kvm_vm_ioctl(KVM_SET_TSS_ADDR, 0xfffbd000); +#endif + /* Set TSS base one page after EPT identity map. */ + ret = kvm_vm_ioctl(KVM_SET_TSS_ADDR, identity_base + 0x1000); + if (ret < 0) { + return ret; + } + + /* Tell fw_cfg to notify the BIOS to reserve the range. */ + ret = e820_add_entry(identity_base, 0x4000, E820_RESERVED); if (ret < 0) { + fprintf(stderr, "e820_add_entry() table is full\n"); return ret; } - return kvm_init_identity_map_page(); + return 0; } static void set_v8086_seg(struct kvm_segment *lhs, const SegmentCache *rhs)