From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eduardo Habkost Subject: [PATCH 05/12] x86: asm/virtext.h: add cpu_vmxoff() inline function Date: Mon, 17 Nov 2008 19:03:17 -0200 Message-ID: <1226955804-16802-6-git-send-email-ehabkost@redhat.com> References: <1226955804-16802-1-git-send-email-ehabkost@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Andrew Morton , Zachary Amsden , Eduardo Habkost , kvm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, kexec-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, "Rafael J. Wysocki" , Haren Myneni , Simon Horman , "Eric W. Biederman" , Andrey Borzenkov , mingo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, Vivek Goyal To: Avi Kivity , Ingo Molnar Return-path: In-Reply-To: <1226955804-16802-1-git-send-email-ehabkost-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kexec-bounces-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org Errors-To: kexec-bounces+glkk-kexec=m.gmane.org-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: kvm.vger.kernel.org Unfortunately we can't use exactly the same code from vmx hardware_disable(), because the KVM function uses the __kvm_handle_fault_on_reboot() tricks. Signed-off-by: Eduardo Habkost --- arch/x86/include/asm/virtext.h | 15 +++++++++++++++ 1 files changed, 15 insertions(+), 0 deletions(-) diff --git a/arch/x86/include/asm/virtext.h b/arch/x86/include/asm/virtext.h index 298b6a0..7dee5b5 100644 --- a/arch/x86/include/asm/virtext.h +++ b/arch/x86/include/asm/virtext.h @@ -18,6 +18,8 @@ #include #include +#include + /* * VMX functions: */ @@ -28,4 +30,17 @@ static inline int cpu_has_vmx(void) return test_bit(5, &ecx); /* CPUID.1:ECX.VMX[bit 5] -> VT */ } + +/** Disable VMX on the current CPU + * + * vmxoff causes a undefined-opcode exception if vmxon was not run + * on the CPU previously. Only call this function if you know VMX + * is enabled. + */ +static inline void cpu_vmxoff(void) +{ + asm volatile (ASM_VMX_VMXOFF : : : "cc"); + write_cr4(read_cr4() & ~X86_CR4_VMXE); +} + #endif /* _ASM_X86_VIRTEX_H */ -- 1.5.5.GIT