Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753101Ab2B0PI3 (ORCPT ); Mon, 27 Feb 2012 10:08:29 -0500 Received: from thoth.sbs.de ([192.35.17.2]:22488 "EHLO thoth.sbs.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752599Ab2B0PI1 (ORCPT ); Mon, 27 Feb 2012 10:08:27 -0500 Message-ID: <4F4B9C57.3010407@siemens.com> Date: Mon, 27 Feb 2012 16:08:07 +0100 From: Jan Kiszka User-Agent: Mozilla/5.0 (X11; U; Linux i686 (x86_64); de; rv:1.8.1.12) Gecko/20080226 SUSE/2.0.0.12-1.1 Thunderbird/2.0.0.12 Mnenhy/0.7.5.666 MIME-Version: 1.0 To: Wen Congyang CC: kvm list , Avi Kivity , KAMEZAWA Hiroyuki , "Daniel P. Berrange" , linux-kernel@vger.kernel.org, qemu-devel Subject: Re: [PATCH] kvm: notify host when guest paniced References: <4F4AF1FB.6000903@cn.fujitsu.com> In-Reply-To: <4F4AF1FB.6000903@cn.fujitsu.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5464 Lines: 177 On 2012-02-27 04:01, Wen Congyang wrote: > We can know the guest is paniced when the guest runs on xen. > But we do not have such feature on kvm. This patch implemnts > this feature, and the implementation is the same as xen: > register panic notifier, and call hypercall when the guest > is paniced. > > Signed-off-by: Wen Congyang > --- > arch/x86/kernel/kvm.c | 12 ++++++++++++ > arch/x86/kvm/svm.c | 8 ++++++-- > arch/x86/kvm/vmx.c | 8 ++++++-- > arch/x86/kvm/x86.c | 13 +++++++++++-- > include/linux/kvm.h | 1 + > include/linux/kvm_para.h | 1 + > 6 files changed, 37 insertions(+), 6 deletions(-) > > diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c > index f0c6fd6..b928d1d 100644 > --- a/arch/x86/kernel/kvm.c > +++ b/arch/x86/kernel/kvm.c > @@ -331,6 +331,17 @@ static struct notifier_block kvm_pv_reboot_nb = { > .notifier_call = kvm_pv_reboot_notify, > }; > > +static int > +kvm_pv_panic_notify(struct notifier_block *nb, unsigned long code, void *unused) > +{ > + kvm_hypercall0(KVM_HC_GUEST_PANIC); > + return NOTIFY_DONE; > +} > + > +static struct notifier_block kvm_pv_panic_nb = { > + .notifier_call = kvm_pv_panic_notify, > +}; > + You should split up host and guest-side changes. > static u64 kvm_steal_clock(int cpu) > { > u64 steal; > @@ -417,6 +428,7 @@ void __init kvm_guest_init(void) > > paravirt_ops_setup(); > register_reboot_notifier(&kvm_pv_reboot_nb); > + atomic_notifier_chain_register(&panic_notifier_list, &kvm_pv_panic_nb); > for (i = 0; i < KVM_TASK_SLEEP_HASHSIZE; i++) > spin_lock_init(&async_pf_sleepers[i].lock); > if (kvm_para_has_feature(KVM_FEATURE_ASYNC_PF)) > diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c > index 0b7690e..38b4705 100644 > --- a/arch/x86/kvm/svm.c > +++ b/arch/x86/kvm/svm.c > @@ -1900,10 +1900,14 @@ static int halt_interception(struct vcpu_svm *svm) > > static int vmmcall_interception(struct vcpu_svm *svm) > { > + int ret; > + > svm->next_rip = kvm_rip_read(&svm->vcpu) + 3; > skip_emulated_instruction(&svm->vcpu); > - kvm_emulate_hypercall(&svm->vcpu); > - return 1; > + ret = kvm_emulate_hypercall(&svm->vcpu); > + > + /* Ignore the error? */ > + return ret == 0 ? 0 : 1; Why can't kvm_emulate_hypercall return the right value? > } > > static unsigned long nested_svm_get_tdp_cr3(struct kvm_vcpu *vcpu) > diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c > index 66147ca..1b57ebb 100644 > --- a/arch/x86/kvm/vmx.c > +++ b/arch/x86/kvm/vmx.c > @@ -4582,9 +4582,13 @@ static int handle_halt(struct kvm_vcpu *vcpu) > > static int handle_vmcall(struct kvm_vcpu *vcpu) > { > + int ret; > + > skip_emulated_instruction(vcpu); > - kvm_emulate_hypercall(vcpu); > - return 1; > + ret = kvm_emulate_hypercall(vcpu); > + > + /* Ignore the error? */ > + return ret == 0 ? 0 : 1; > } > > static int handle_invd(struct kvm_vcpu *vcpu) > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index c9d99e5..3fc2853 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -4923,7 +4923,7 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu) > u64 param, ingpa, outgpa, ret; > uint16_t code, rep_idx, rep_cnt, res = HV_STATUS_SUCCESS, rep_done = 0; > bool fast, longmode; > - int cs_db, cs_l; > + int cs_db, cs_l, r = 1; > > /* > * hypercall generates UD from non zero cpl and real mode > @@ -4964,6 +4964,10 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu) > case HV_X64_HV_NOTIFY_LONG_SPIN_WAIT: > kvm_vcpu_on_spin(vcpu); > break; > + case KVM_HC_GUEST_PANIC: > + vcpu->run->exit_reason = KVM_EXIT_GUEST_PANIC; > + r = 0; > + break; That's the wrong place. This is a KVM hypercall, not a HyperV one. > default: > res = HV_STATUS_INVALID_HYPERCALL_CODE; > break; > @@ -4977,7 +4981,7 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu) > kvm_register_write(vcpu, VCPU_REGS_RAX, ret & 0xffffffff); > } > > - return 1; > + return r; > } > > int kvm_emulate_hypercall(struct kvm_vcpu *vcpu) > @@ -5013,6 +5017,11 @@ int kvm_emulate_hypercall(struct kvm_vcpu *vcpu) > case KVM_HC_VAPIC_POLL_IRQ: > ret = 0; > break; > + case KVM_HC_GUEST_PANIC: > + ret = 0; > + vcpu->run->exit_reason = KVM_EXIT_GUEST_PANIC; > + r = 0; > + break; > default: > ret = -KVM_ENOSYS; > break; > diff --git a/include/linux/kvm.h b/include/linux/kvm.h > index acbe429..8f0e31b 100644 > --- a/include/linux/kvm.h > +++ b/include/linux/kvm.h > @@ -163,6 +163,7 @@ struct kvm_pit_config { > #define KVM_EXIT_OSI 18 > #define KVM_EXIT_PAPR_HCALL 19 > #define KVM_EXIT_S390_UCONTROL 20 > +#define KVM_EXIT_GUEST_PANIC 21 > > /* For KVM_EXIT_INTERNAL_ERROR */ > #define KVM_INTERNAL_ERROR_EMULATION 1 > diff --git a/include/linux/kvm_para.h b/include/linux/kvm_para.h > index ff476dd..cf94023 100644 > --- a/include/linux/kvm_para.h > +++ b/include/linux/kvm_para.h > @@ -19,6 +19,7 @@ > #define KVM_HC_MMU_OP 2 > #define KVM_HC_FEATURES 3 > #define KVM_HC_PPC_MAP_MAGIC_PAGE 4 > +#define KVM_HC_GUEST_PANIC 5 > > /* > * hypercalls use architecture specific Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/