From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752709AbeDQLeN (ORCPT ); Tue, 17 Apr 2018 07:34:13 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:34120 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752048AbeDQLeL (ORCPT ); Tue, 17 Apr 2018 07:34:11 -0400 Date: Tue, 17 Apr 2018 13:34:03 +0200 From: Cornelia Huck To: Tony Krowiak Cc: linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, freude@de.ibm.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, borntraeger@de.ibm.com, kwankhede@nvidia.com, bjsdjshi@linux.vnet.ibm.com, pbonzini@redhat.com, alex.williamson@redhat.com, pmorel@linux.vnet.ibm.com, alifm@linux.vnet.ibm.com, mjrosato@linux.vnet.ibm.com, jjherne@linux.vnet.ibm.com, thuth@redhat.com, pasic@linux.vnet.ibm.com, berrange@redhat.com, fiuczy@linux.vnet.ibm.com, buendgen@de.ibm.com Subject: Re: [PATCH v4 02/15] KVM: s390: reset crypto attributes for all vcpus Message-ID: <20180417133403.6fd7627a.cohuck@redhat.com> In-Reply-To: <1523827345-11600-3-git-send-email-akrowiak@linux.vnet.ibm.com> References: <1523827345-11600-1-git-send-email-akrowiak@linux.vnet.ibm.com> <1523827345-11600-3-git-send-email-akrowiak@linux.vnet.ibm.com> Organization: Red Hat GmbH MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 15 Apr 2018 17:22:12 -0400 Tony Krowiak wrote: > Introduces a new function to reset the crypto attributes for all > vcpus whether they are running or not. Each vcpu in KVM will > be removed from SIE prior to resetting the crypto attributes in its > SIE state description. After all vcpus have had their crypto attributes > reset the vcpus will be restored to SIE. > > This function will be used in a later patch to set the ECA.28 > bit in the SIE state description to enable interpretive execution of > AP instructions. It will also be incorporated into the > kvm_s390_vm_set_crypto(kvm) function to fix an issue whereby the crypto > key wrapping attributes could potentially get out of synch for running > vcpus. So, this description leads me to think it would make sense to queue this patch (fixing the key wrapping) independently of this series, wouldn't it? > > Signed-off-by: Tony Krowiak > --- > arch/s390/kvm/kvm-s390.c | 19 +++++++++++++------ > arch/s390/kvm/kvm-s390.h | 14 ++++++++++++++ > 2 files changed, 27 insertions(+), 6 deletions(-) > > diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c > index 64c9862..d0c3518 100644 > --- a/arch/s390/kvm/kvm-s390.c > +++ b/arch/s390/kvm/kvm-s390.c > @@ -791,11 +791,21 @@ static int kvm_s390_set_mem_control(struct kvm *kvm, struct kvm_device_attr *att > > static void kvm_s390_vcpu_crypto_setup(struct kvm_vcpu *vcpu); > > -static int kvm_s390_vm_set_crypto(struct kvm *kvm, struct kvm_device_attr *attr) > +void kvm_s390_vcpu_crypto_reset_all(struct kvm *kvm) _reset_all() or _set_all()? Don't really care much, tbh. > { > - struct kvm_vcpu *vcpu; > int i; > + struct kvm_vcpu *vcpu; I'd avoid swapping the order of the declarations. > + > + kvm_s390_vcpu_block_all(kvm); > + > + kvm_for_each_vcpu(i, vcpu, kvm) > + kvm_s390_vcpu_crypto_setup(vcpu); > > + kvm_s390_vcpu_unblock_all(kvm); > +} > + > +static int kvm_s390_vm_set_crypto(struct kvm *kvm, struct kvm_device_attr *attr) > +{ > if (!test_kvm_facility(kvm, 76)) > return -EINVAL; > > @@ -832,10 +842,7 @@ static int kvm_s390_vm_set_crypto(struct kvm *kvm, struct kvm_device_attr *attr) > return -ENXIO; > } > > - kvm_for_each_vcpu(i, vcpu, kvm) { > - kvm_s390_vcpu_crypto_setup(vcpu); > - exit_sie(vcpu); > - } > + kvm_s390_vcpu_crypto_reset_all(kvm); > mutex_unlock(&kvm->lock); > return 0; > } > diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h > index 1b5621f..76324b7 100644 > --- a/arch/s390/kvm/kvm-s390.h > +++ b/arch/s390/kvm/kvm-s390.h > @@ -410,4 +410,18 @@ static inline int kvm_s390_use_sca_entries(void) > } > void kvm_s390_reinject_machine_check(struct kvm_vcpu *vcpu, > struct mcck_volatile_info *mcck_info); > + > +/** > + * kvm_s390_vcpu_crypto_reset_all > + * > + * Reset the crypto attributes for each vcpu. This can be done while the vcpus > + * are running as each vcpu will be removed from SIE before resetting the crypto > + * attributes and restored to SIE afterward. > + * > + * Note: The kvm->lock mutex must be locked prior to calling this function and > + * unlocked after it returns. "Must be called with kvm->lock held"? > + * > + * @kvm: the KVM guest > + */ > +void kvm_s390_vcpu_crypto_reset_all(struct kvm *kvm); > #endif Other than the nits above, looks good to me.