From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52262) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zx6Mm-0006FU-4v for qemu-devel@nongnu.org; Thu, 12 Nov 2015 23:53:41 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Zx6Mh-0005yO-4d for qemu-devel@nongnu.org; Thu, 12 Nov 2015 23:53:40 -0500 Received: from e39.co.us.ibm.com ([32.97.110.160]:33768) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zx6Mg-0005x7-Tu for qemu-devel@nongnu.org; Thu, 12 Nov 2015 23:53:35 -0500 Received: from localhost by e39.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 12 Nov 2015 21:53:33 -0700 Message-ID: <56456CC0.2060906@linux.vnet.ibm.com> Date: Fri, 13 Nov 2015 10:23:20 +0530 From: Aravinda Prasad MIME-Version: 1.0 References: <20151111171135.4328.41819.stgit@aravindap> <20151111171602.4328.34006.stgit@aravindap> <56444957.9080003@redhat.com> <5644D931.1070407@linux.vnet.ibm.com> <20151113015816.GK4886@voom.redhat.com> In-Reply-To: <20151113015816.GK4886@voom.redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 4/4] target-ppc: Handle NMI guest exit List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: David Gibson Cc: Thomas Huth , benh@au1.ibm.com, aik@ozlabs.ru, agraf@suse.de, qemu-devel@nongnu.org, qemu-ppc@nongnu.org, paulus@samba.org, sam.bobroff@au1.ibm.com On Friday 13 November 2015 07:28 AM, David Gibson wrote: > On Thu, Nov 12, 2015 at 11:53:45PM +0530, Aravinda Prasad wrote: >> >> >> On Thursday 12 November 2015 01:39 PM, Thomas Huth wrote: >>> On 11/11/15 18:16, Aravinda Prasad wrote: >>>> Memory error such as bit flips that cannot be corrected >>>> by hardware are passed on to the kernel for handling. >>>> If the memory address in error belongs to guest then >>>> guest kernel is responsible for taking suitable action. >>>> Patch [1] enhances KVM to exit guest with exit reason >>>> set to KVM_EXIT_NMI in such cases. >>>> >>>> This patch handles KVM_EXIT_NMI exit. If the guest OS >>>> has registered the machine check handling routine by >>>> calling "ibm,nmi-register", then the handler builds >>>> the error log and invokes the registered handler else >>>> invokes the handler at 0x200. >>>> >>>> [1] http://marc.info/?l=kvm-ppc&m=144726114408289 >>>> >>>> Signed-off-by: Aravinda Prasad >>>> --- >>>> target-ppc/kvm.c | 69 +++++++++++++++++++++++++++++++++++++++++++ >>>> target-ppc/kvm_ppc.h | 81 ++++++++++++++++++++++++++++++++++++++++++++++++++ >>>> 2 files changed, 150 insertions(+) >>>> >>>> diff --git a/target-ppc/kvm.c b/target-ppc/kvm.c >>>> index 110436d..e2e5170 100644 >>>> --- a/target-ppc/kvm.c >>>> +++ b/target-ppc/kvm.c >>>> @@ -1665,6 +1665,11 @@ int kvm_arch_handle_exit(CPUState *cs, struct kvm_run *run) >>>> ret = 0; >>>> break; >>>> >>>> + case KVM_EXIT_NMI: >>>> + DPRINTF("handle NMI exception\n"); >>>> + ret = kvm_handle_nmi(cpu); >>>> + break; >>>> + >>>> default: >>>> fprintf(stderr, "KVM: unknown exit reason %d\n", run->exit_reason); >>>> ret = -1; >>>> @@ -2484,3 +2489,67 @@ int kvm_arch_msi_data_to_gsi(uint32_t data) >>>> { >>>> return data & 0xffff; >>>> } >>>> + >>>> +int kvm_handle_nmi(PowerPCCPU *cpu) >>>> +{ >>>> + struct rtas_mc_log mc_log; >>>> + CPUPPCState *env = &cpu->env; >>>> + sPAPRMachineState *spapr = SPAPR_MACHINE(qdev_get_machine()); >>>> + PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu); >>>> + >>>> + cpu_synchronize_state(CPU(ppc_env_get_cpu(env))); >>>> + >>>> + /* Properly set bits in MSR before we invoke the handler */ >>>> + env->msr = 0; >>>> + >>>> + if (!(*pcc->interrupts_big_endian)(cpu)) { >>>> + env->msr |= (1ULL << MSR_LE); >>>> + } >>>> + >>>> +#ifdef TARGET_PPC64 >>>> + env->msr |= (1ULL << MSR_SF); >>>> +#endif >>>> + >>>> + if (!spapr->guest_machine_check_addr) { >>>> + /* >>>> + * If OS has not registered with "ibm,nmi-register" >>>> + * jump to 0x200 >>>> + */ >>> >>> Shouldn't you also check MSR_ME here first and enter checkstop when >>> machine checks are disabled? >> >> Yes, MSR_ME should be checked first. >> >>> Also I think you have to set up some more registers for machine check >>> interrupts, like SRR0 and SRR1? >> >> SRRO and SRR1 of vcpu are properly set in KVM in kvmppc_interrupt_hv. I >> am not sure if any other registers need to be set. > > DAR and DSISR are the obvious ones you need to consider, although I > suspect they're already set up correctly by the kernel, too. Yes, they are also setup properly by KVM. Regards, Aravinda > -- Regards, Aravinda