From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:40041) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1REgQU-00029E-Hq for qemu-devel@nongnu.org; Fri, 14 Oct 2011 07:59:48 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1REgQT-0002B3-69 for qemu-devel@nongnu.org; Fri, 14 Oct 2011 07:59:46 -0400 Received: from mail-wy0-f173.google.com ([74.125.82.173]:43573) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1REgQT-0002An-1j for qemu-devel@nongnu.org; Fri, 14 Oct 2011 07:59:45 -0400 Received: by wyh22 with SMTP id 22so3259690wyh.4 for ; Fri, 14 Oct 2011 04:59:43 -0700 (PDT) From: Sasha Levin In-Reply-To: <4E980621.9050301@cn.fujitsu.com> References: <20110913093835.GB4265@localhost.localdomain> <20110914093441.e2bb305c.kamezawa.hiroyu@jp.fujitsu.com> <4E705BC3.5000508@cn.fujitsu.com> <20110915164704.9cacd407.kamezawa.hiroyu@jp.fujitsu.com> <4E71B28F.7030201@cn.fujitsu.com> <4E72F3BA.2000603@jp.fujitsu.com> <4E73200A.7040908@jp.fujitsu.com> <4E76C6AA.9080403@cn.fujitsu.com> <4E7B04DC.1030407@cn.fujitsu.com> <4E7B4B8F.507@siemens.com> <4E7C51E4.2000503@cn.fujitsu.com> <4E7F3585.40108@redhat.com> <4E7F635E.6080009@web.de> <4E8035F9.9080908@redhat.com> <4E928B54.1070707@cn.fujitsu.com> <4E92958E.9000509@web.de> <4E9476E2.1070804@cn.fujitsu.com> <4E948842.4030406@web.de> <4E978827.6070008@cn.fujitsu.com> <4E97CE42.9020102@web.de> <4E97D85C.7070107@cn.fujitsu.com> <4E97DB62.9020605@web.de> <4E980621.9050301@cn.fujitsu.com> Content-Type: text/plain; charset="us-ascii" Date: Fri, 14 Oct 2011 13:59:36 +0200 Message-ID: <1318593576.2827.18.camel@sasha> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 1/1 V5 tuning] kernel/kvm: introduce KVM_SET_LINT1 and fix improper nmi emulation List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Lai Jiangshan Cc: "kvm@vger.kernel.org" , "qemu-devel@nongnu.org" , Jan Kiszka , Avi Kivity , Kenji Kaneshige , KAMEZAWA Hiroyuki On Fri, 2011-10-14 at 17:51 +0800, Lai Jiangshan wrote: > Currently, NMI interrupt is blindly sent to all the vCPUs when NMI > button event happens. This doesn't properly emulate real hardware on > which NMI button event triggers LINT1. Because of this, NMI is sent to > the processor even when LINT1 is masked in LVT. For example, this > causes the problem that kdump initiated by NMI sometimes doesn't work > on KVM, because kdump assumes NMI is masked on CPUs other than CPU0. > > With this patch, we introduce introduce KVM_SET_LINT1, > and we can use KVM_SET_LINT1 to correctly emulate NMI button > without change the old KVM_NMI behavior. > > Signed-off-by: Lai Jiangshan > Reported-by: Kenji Kaneshige > --- It could use a documentation update as well. > arch/x86/kvm/irq.h | 1 + > arch/x86/kvm/lapic.c | 7 +++++++ > arch/x86/kvm/x86.c | 8 ++++++++ > include/linux/kvm.h | 3 +++ > 4 files changed, 19 insertions(+), 0 deletions(-) > diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h > index 53e2d08..0c96315 100644 > --- a/arch/x86/kvm/irq.h > +++ b/arch/x86/kvm/irq.h > @@ -95,6 +95,7 @@ void kvm_pic_reset(struct kvm_kpic_state *s); > void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu); > void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu); > void kvm_apic_nmi_wd_deliver(struct kvm_vcpu *vcpu); > +void kvm_apic_lint1_deliver(struct kvm_vcpu *vcpu); > void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu); > void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu); > void __kvm_migrate_timers(struct kvm_vcpu *vcpu); > diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c > index 57dcbd4..87fe36a 100644 > --- a/arch/x86/kvm/lapic.c > +++ b/arch/x86/kvm/lapic.c > @@ -1039,6 +1039,13 @@ void kvm_apic_nmi_wd_deliver(struct kvm_vcpu *vcpu) > kvm_apic_local_deliver(apic, APIC_LVT0); > } > > +void kvm_apic_lint1_deliver(struct kvm_vcpu *vcpu) > +{ > + struct kvm_lapic *apic = vcpu->arch.apic; > + > + kvm_apic_local_deliver(apic, APIC_LVT1); > +} > + > static struct kvm_timer_ops lapic_timer_ops = { > .is_periodic = lapic_is_periodic, > }; > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index 84a28ea..fccd094 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -2077,6 +2077,7 @@ int kvm_dev_ioctl_check_extension(long ext) > case KVM_CAP_XSAVE: > case KVM_CAP_ASYNC_PF: > case KVM_CAP_GET_TSC_KHZ: > + case KVM_CAP_SET_LINT1: > r = 1; > break; > case KVM_CAP_COALESCED_MMIO: > @@ -3264,6 +3265,13 @@ long kvm_arch_vcpu_ioctl(struct file *filp, > > goto out; > } > + case KVM_SET_LINT1: { > + r = -EINVAL; > + if (!irqchip_in_kernel(vcpu->kvm)) > + goto out; > + r = 0; > + kvm_apic_lint1_deliver(vcpu); We simply ignore the return value of kvm_apic_local_deliver() and assume it always works. why? -- Sasha.