From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753447Ab3HEN6B (ORCPT ); Mon, 5 Aug 2013 09:58:01 -0400 Received: from terminus.zytor.com ([198.137.202.10]:51659 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753147Ab3HEN57 (ORCPT ); Mon, 5 Aug 2013 09:57:59 -0400 Date: Mon, 5 Aug 2013 06:57:41 -0700 From: tip-bot for Jason Wang Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@kernel.org, jasowang@redhat.com, gleb@redhat.com, pbonzini@redhat.com, tglx@linutronix.de, hpa@linux.intel.com Reply-To: mingo@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org, jasowang@redhat.com, gleb@redhat.com, pbonzini@redhat.com, tglx@linutronix.de, hpa@linux.intel.com In-Reply-To: <1374742475-2485-1-git-send-email-jasowang@redhat.com> References: <1374742475-2485-1-git-send-email-jasowang@redhat.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/paravirt] x86: Introduce hypervisor_cpuid_base() Git-Commit-ID: 96e39ac0e9d18020c8c5a41b64b8fe86c26575ab X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.7 (terminus.zytor.com [127.0.0.1]); Mon, 05 Aug 2013 06:57:48 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 96e39ac0e9d18020c8c5a41b64b8fe86c26575ab Gitweb: http://git.kernel.org/tip/96e39ac0e9d18020c8c5a41b64b8fe86c26575ab Author: Jason Wang AuthorDate: Thu, 25 Jul 2013 16:54:32 +0800 Committer: H. Peter Anvin CommitDate: Mon, 5 Aug 2013 06:33:54 -0700 x86: Introduce hypervisor_cpuid_base() This patch introduce hypervisor_cpuid_base() which loop test the hypervisor existence function until the signature match and check the number of leaves if required. This could be used by Xen/KVM guest to detect the existence of hypervisor. Cc: Paolo Bonzini Cc: Gleb Natapov Signed-off-by: Jason Wang Link: http://lkml.kernel.org/r/1374742475-2485-1-git-send-email-jasowang@redhat.com Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/processor.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 24cf5ae..7763307 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -971,6 +971,21 @@ unsigned long calc_aperfmperf_ratio(struct aperfmperf *old, return ratio; } +static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves) +{ + uint32_t base, eax, signature[3]; + + for (base = 0x40000000; base < 0x40010000; base += 0x100) { + cpuid(base, &eax, &signature[0], &signature[1], &signature[2]); + + if (!memcmp(sig, signature, 12) && + (leaves == 0 || ((eax - base) >= leaves))) + return base; + } + + return 0; +} + extern unsigned long arch_align_stack(unsigned long sp); extern void free_init_pages(char *what, unsigned long begin, unsigned long end);