From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:34064 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726897AbfK2OeB (ORCPT ); Fri, 29 Nov 2019 09:34:01 -0500 Subject: Re: [PATCH] KVM: s390: Add new reset vcpu API References: <20191129142122.21528-1-frankja@linux.ibm.com> <8e1aa1af-d929-e36b-f341-aa7dbe27f6a4@linux.ibm.com> From: David Hildenbrand Message-ID: <227a8fce-7e14-030e-b0a4-17e4521eed98@redhat.com> Date: Fri, 29 Nov 2019 15:33:53 +0100 MIME-Version: 1.0 In-Reply-To: <8e1aa1af-d929-e36b-f341-aa7dbe27f6a4@linux.ibm.com> Content-Language: en-US Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-s390-owner@vger.kernel.org List-ID: To: Janosch Frank , kvm@vger.kernel.org Cc: thuth@redhat.com, borntraeger@de.ibm.com, mihajlov@linux.ibm.com, cohuck@redhat.com, linux-s390@vger.kernel.org On 29.11.19 15:33, Janosch Frank wrote: > On 11/29/19 3:31 PM, David Hildenbrand wrote: >> On 29.11.19 15:21, Janosch Frank wrote: >>> The architecture states that we need to reset local IRQs for all CPU >>> resets. Because the old reset interface did not support the normal CPU >>> reset we never did that. >>> >>> Now that we have a new interface, let's properly clear out local IRQs >>> and let this commit be a reminder. >>> >>> Signed-off-by: Janosch Frank >>> --- >>> arch/s390/kvm/kvm-s390.c | 25 ++++++++++++++++++++++++- >>> include/uapi/linux/kvm.h | 7 +++++++ >>> 2 files changed, 31 insertions(+), 1 deletion(-) >>> >>> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c >>> index d9e6bf3d54f0..2f74ff46b176 100644 >>> --- a/arch/s390/kvm/kvm-s390.c >>> +++ b/arch/s390/kvm/kvm-s390.c >>> @@ -529,6 +529,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) >>> case KVM_CAP_S390_CMMA_MIGRATION: >>> case KVM_CAP_S390_AIS: >>> case KVM_CAP_S390_AIS_MIGRATION: >>> + case KVM_CAP_S390_VCPU_RESETS: >>> r = 1; >>> break; >>> case KVM_CAP_S390_HPAGE_1M: >>> @@ -3293,6 +3294,25 @@ static int kvm_arch_vcpu_ioctl_initial_reset(struct kvm_vcpu *vcpu) >>> return 0; >>> } >>> >>> +static int kvm_arch_vcpu_ioctl_reset(struct kvm_vcpu *vcpu, unsigned long type) >>> +{ >>> + int rc = -EINVAL; >>> + >>> + switch (type) { >>> + case KVM_S390_VCPU_RESET_NORMAL: >>> + rc = 0; >>> + kvm_clear_async_pf_completion_queue(vcpu); >>> + kvm_s390_clear_local_irqs(vcpu); >>> + break; >>> + case KVM_S390_VCPU_RESET_INITIAL: >>> + /* fallthrough */ >>> + case KVM_S390_VCPU_RESET_CLEAR: >>> + rc = kvm_arch_vcpu_ioctl_initial_reset(vcpu); >> >> As we now have two interfaces to achieve the same thing (initial reset), >> I do wonder if we should simply introduce >> >> KVM_S390_NORMAL_RESET >> KVM_S390_CLEAR_RESET >> >> instead ... >> >> Then you can do KVM_S390_NORMAL_RESET for the bugfix and >> KVM_S390_CLEAR_RESET later for PV. >> >> Does anything speak against that? > > Apart from loosing one more ioctl number probably not Do we care? (I think not, but maybe I am missing something :) ) -- Thanks, David / dhildenb