From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932190AbYDQJRM (ORCPT ); Thu, 17 Apr 2008 05:17:12 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760110AbYDQJLM (ORCPT ); Thu, 17 Apr 2008 05:11:12 -0400 Received: from bzq-179-150-194.static.bezeqint.net ([212.179.150.194]:58956 "EHLO il.qumranet.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759434AbYDQJK6 (ORCPT ); Thu, 17 Apr 2008 05:10:58 -0400 From: Avi Kivity To: kvm-devel@lists.sourceforge.net Cc: linux-kernel@vger.kernel.org, Christian Borntraeger Subject: [PATCH 15/45] s390: KVM guest: detect when running on kvm Date: Thu, 17 Apr 2008 12:10:20 +0300 Message-Id: <1208423450-29415-16-git-send-email-avi@qumranet.com> X-Mailer: git-send-email 1.5.5 In-Reply-To: <1208423450-29415-1-git-send-email-avi@qumranet.com> References: <1208423450-29415-1-git-send-email-avi@qumranet.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Christian Borntraeger From: Carsten Otte This patch adds functionality to detect if the kernel runs under the KVM hypervisor. A macro MACHINE_IS_KVM is exported for device drivers. This allows drivers to skip device detection if the systems runs non-virtualized. We also define a preferred console to avoid having the ttyS0, which is a line mode only console. Signed-off-by: Christian Borntraeger Acked-by: Martin Schwidefsky Signed-off-by: Carsten Otte Signed-off-by: Avi Kivity --- arch/s390/Kconfig | 7 +++++++ arch/s390/kernel/early.c | 4 ++++ arch/s390/kernel/setup.c | 10 +++++++--- include/asm-s390/setup.h | 1 + 4 files changed, 19 insertions(+), 3 deletions(-) diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index c43b250..235ddce 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -533,6 +533,13 @@ config ZFCPDUMP Select this option if you want to build an zfcpdump enabled kernel. Refer to for more details on this. +config S390_GUEST +bool "s390 guest support (EXPERIMENTAL)" + depends on 64BIT && EXPERIMENTAL + select VIRTIO + select VIRTIO_RING + help + Select this option if you want to run the kernel under s390 linux endmenu source "net/Kconfig" diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c index 01832c4..9886578 100644 --- a/arch/s390/kernel/early.c +++ b/arch/s390/kernel/early.c @@ -143,6 +143,10 @@ static noinline __init void detect_machine_type(void) /* Running on a P/390 ? */ if (cpuinfo->cpu_id.machine == 0x7490) machine_flags |= 4; + + /* Running under KVM ? */ + if (cpuinfo->cpu_id.version == 0xfe) + machine_flags |= 64; } #ifdef CONFIG_64BIT diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c index 526c135..c64bfb4 100644 --- a/arch/s390/kernel/setup.c +++ b/arch/s390/kernel/setup.c @@ -793,9 +793,13 @@ setup_arch(char **cmdline_p) "This machine has an IEEE fpu\n" : "This machine has no IEEE fpu\n"); #else /* CONFIG_64BIT */ - printk((MACHINE_IS_VM) ? - "We are running under VM (64 bit mode)\n" : - "We are running native (64 bit mode)\n"); + if (MACHINE_IS_VM) + printk("We are running under VM (64 bit mode)\n"); + else if (MACHINE_IS_KVM) { + printk("We are running under KVM (64 bit mode)\n"); + add_preferred_console("ttyS", 1, NULL); + } else + printk("We are running native (64 bit mode)\n"); #endif /* CONFIG_64BIT */ /* Save unparsed command line copy for /proc/cmdline */ diff --git a/include/asm-s390/setup.h b/include/asm-s390/setup.h index a76a6b8..aaf4b51 100644 --- a/include/asm-s390/setup.h +++ b/include/asm-s390/setup.h @@ -62,6 +62,7 @@ extern unsigned long machine_flags; #define MACHINE_IS_VM (machine_flags & 1) #define MACHINE_IS_P390 (machine_flags & 4) #define MACHINE_HAS_MVPG (machine_flags & 16) +#define MACHINE_IS_KVM (machine_flags & 64) #define MACHINE_HAS_IDTE (machine_flags & 128) #define MACHINE_HAS_DIAG9C (machine_flags & 256) -- 1.5.5