From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:49099 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726267AbgBQLBU (ORCPT ); Mon, 17 Feb 2020 06:01:20 -0500 Subject: Re: [PATCH v2 19/42] KVM: s390: protvirt: Add new gprs location handling References: <20200214222658.12946-1-borntraeger@de.ibm.com> <20200214222658.12946-20-borntraeger@de.ibm.com> From: David Hildenbrand Message-ID: <38b60f61-db18-ee7a-6b8e-192a7bb9d259@redhat.com> Date: Mon, 17 Feb 2020 12:01:03 +0100 MIME-Version: 1.0 In-Reply-To: <20200214222658.12946-20-borntraeger@de.ibm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-s390-owner@vger.kernel.org List-ID: To: Christian Borntraeger , Janosch Frank Cc: KVM , Cornelia Huck , Thomas Huth , Ulrich Weigand , Claudio Imbrenda , linux-s390 , Michael Mueller , Vasily Gorbik , Janosch Frank On 14.02.20 23:26, Christian Borntraeger wrote: > From: Janosch Frank > > Guest registers for protected guests are stored at offset 0x380. > > Signed-off-by: Janosch Frank > Reviewed-by: Thomas Huth > Reviewed-by: Cornelia Huck > [borntraeger@de.ibm.com: patch merging, splitting, fixing] > Signed-off-by: Christian Borntraeger > --- > arch/s390/include/asm/kvm_host.h | 4 +++- > arch/s390/kvm/kvm-s390.c | 11 +++++++++++ > 2 files changed, 14 insertions(+), 1 deletion(-) > > diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h > index ba3364b37159..4fcbb055a565 100644 > --- a/arch/s390/include/asm/kvm_host.h > +++ b/arch/s390/include/asm/kvm_host.h > @@ -343,7 +343,9 @@ struct kvm_s390_itdb { > struct sie_page { > struct kvm_s390_sie_block sie_block; > struct mcck_volatile_info mcck_info; /* 0x0200 */ > - __u8 reserved218[1000]; /* 0x0218 */ > + __u8 reserved218[360]; /* 0x0218 */ > + __u64 pv_grregs[16]; /* 0x0380 */ > + __u8 reserved400[512]; /* 0x0400 */ > struct kvm_s390_itdb itdb; /* 0x0600 */ > __u8 reserved700[2304]; /* 0x0700 */ > }; > diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c > index a85e50075d99..6ebb0dae5a2e 100644 > --- a/arch/s390/kvm/kvm-s390.c > +++ b/arch/s390/kvm/kvm-s390.c > @@ -3999,6 +3999,7 @@ static int vcpu_post_run(struct kvm_vcpu *vcpu, int exit_reason) > static int __vcpu_run(struct kvm_vcpu *vcpu) > { > int rc, exit_reason; > + struct sie_page *sie_page = (struct sie_page *)vcpu->arch.sie_block; > > /* > * We try to hold kvm->srcu during most of vcpu_run (except when run- > @@ -4020,8 +4021,18 @@ static int __vcpu_run(struct kvm_vcpu *vcpu) > guest_enter_irqoff(); > __disable_cpu_timer_accounting(vcpu); > local_irq_enable(); > + if (kvm_s390_pv_is_protected(vcpu->kvm)) { > + memcpy(sie_page->pv_grregs, > + vcpu->run->s.regs.gprs, > + sizeof(sie_page->pv_grregs)); > + } > exit_reason = sie64a(vcpu->arch.sie_block, > vcpu->run->s.regs.gprs); > + if (kvm_s390_pv_is_protected(vcpu->kvm)) { > + memcpy(vcpu->run->s.regs.gprs, > + sie_page->pv_grregs, > + sizeof(sie_page->pv_grregs)); > + } > local_irq_disable(); > __enable_cpu_timer_accounting(vcpu); > guest_exit_irqoff(); > As discussed, I think there is room for improvement in the future (which we could have documented in the patch description), because this is obviously sub-optimal. Reviewed-by: David Hildenbrand -- Thanks, David / dhildenb