From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from [222.73.24.84] (helo=song.cn.fujitsu.com) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1TP5P3-0007zF-94 for kexec@lists.infradead.org; Fri, 19 Oct 2012 05:45:50 +0000 Message-ID: <5080E8BF.3020506@cn.fujitsu.com> Date: Fri, 19 Oct 2012 13:44:31 +0800 From: Zhang Yanfei MIME-Version: 1.0 Subject: [PATCH 1/2] x86/kexec: VMCLEAR vmcss on all cpus if necessary References: <5080E813.7030302@cn.fujitsu.com> In-Reply-To: <5080E813.7030302@cn.fujitsu.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: kexec-bounces@lists.infradead.org Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: x86@kernel.org, kexec@lists.infradead.org, Avi Kivity , mtosatti@redhat.com Cc: linux-kernel@vger.kernel.org, "kvm@vger.kernel.org" This patch provides a way to VMCLEAR vmcss related to guests on all cpus before executing the VMXOFF when doing kdump. This is used to ensure the VMCSs in the vmcore updated and non-corrupted. Signed-off-by: zhangyanfei --- arch/x86/include/asm/kexec.h | 2 ++ arch/x86/kernel/crash.c | 27 +++++++++++++++++++++++++++ 2 files changed, 29 insertions(+), 0 deletions(-) diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h index 317ff17..fc05440 100644 --- a/arch/x86/include/asm/kexec.h +++ b/arch/x86/include/asm/kexec.h @@ -163,6 +163,8 @@ struct kimage_arch { }; #endif +extern void (*crash_clear_loaded_vmcss)(void); + #endif /* __ASSEMBLY__ */ #endif /* _ASM_X86_KEXEC_H */ diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c index 13ad899..7289976 100644 --- a/arch/x86/kernel/crash.c +++ b/arch/x86/kernel/crash.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include @@ -30,6 +31,22 @@ int in_crash_kexec; +/* + * This is used to VMCLEAR vmcss loaded on all + * cpus. And when loading kvm_intel module, the + * function pointer will be made valid. + */ +void (*crash_clear_loaded_vmcss)(void) = NULL; +EXPORT_SYMBOL_GPL(crash_clear_loaded_vmcss); + +static void cpu_emergency_clear_loaded_vmcss(void) +{ + if (crash_clear_loaded_vmcss && + cpu_has_vmx() && cpu_vmx_enabled()) { + crash_clear_loaded_vmcss(); + } +} + #if defined(CONFIG_SMP) && defined(CONFIG_X86_LOCAL_APIC) static void kdump_nmi_callback(int cpu, struct pt_regs *regs) @@ -46,6 +63,11 @@ static void kdump_nmi_callback(int cpu, struct pt_regs *regs) #endif crash_save_cpu(regs, cpu); + /* + * VMCLEAR vmcss loaded on all cpus if needed. + */ + cpu_emergency_clear_loaded_vmcss(); + /* Disable VMX or SVM if needed. * * We need to disable virtualization on all CPUs. @@ -88,6 +110,11 @@ void native_machine_crash_shutdown(struct pt_regs *regs) kdump_nmi_shootdown_cpus(); + /* + * VMCLEAR vmcss loaded on this cpu if needed. + */ + cpu_emergency_clear_loaded_vmcss(); + /* Booting kdump kernel with VMX or SVM enabled won't work, * because (among other limitations) we can't disable paging * with the virt flags. -- 1.7.1 _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec