From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Hildenbrand Subject: Re: [PATCH v10 25/26] KVM: s390: CPU model support for AP virtualization Date: Mon, 24 Sep 2018 10:33:36 +0200 Message-ID: <78df86b6-55f9-f67c-d96a-9c287c0248cd@redhat.com> References: <1536781396-13601-1-git-send-email-akrowiak@linux.vnet.ibm.com> <1536781396-13601-26-git-send-email-akrowiak@linux.vnet.ibm.com> <7868874f-df81-5602-a4c5-a4b58c38d1d3@linux.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <7868874f-df81-5602-a4c5-a4b58c38d1d3@linux.ibm.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-Archive: List-Post: To: Tony Krowiak , Tony Krowiak , linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: freude@de.ibm.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, borntraeger@de.ibm.com, cohuck@redhat.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, frankja@linux.ibm.com List-ID: On 22/09/2018 01:31, Tony Krowiak wrote: > On 09/12/2018 03:43 PM, Tony Krowiak wrote: >> From: Tony Krowiak >> >> Introduces a new CPU model feature and two CPU model >> facilities to support AP virtualization for KVM guests. >> >> CPU model feature: >> >> The KVM_S390_VM_CPU_FEAT_AP feature indicates that >> AP instructions are available on the guest. This >> feature will be enabled by the kernel only if the AP >> instructions are installed on the linux host. This feature >> must be specifically turned on for the KVM guest from >> userspace to use the VFIO AP device driver for guest >> access to AP devices. >> >> CPU model facilities: >> >> 1. AP Query Configuration Information (QCI) facility is installed. >> >> This is indicated by setting facilities bit 12 for >> the guest. The kernel will not enable this facility >> for the guest if it is not set on the host. >> >> If this facility is not set for the KVM guest, then only >> APQNs with an APQI less than 16 will be used by a Linux >> guest regardless of the matrix configuration for the virtual >> machine. This is a limitation of the Linux AP bus. >> >> 2. AP Facilities Test facility (APFT) is installed. >> >> This is indicated by setting facilities bit 15 for >> the guest. The kernel will not enable this facility for >> the guest if it is not set on the host. >> >> If this facility is not set for the KVM guest, then no >> AP devices will be available to the guest regardless of >> the guest's matrix configuration for the virtual >> machine. This is a limitation of the Linux AP bus. >> >> Signed-off-by: Tony Krowiak >> Reviewed-by: Christian Borntraeger >> Reviewed-by: Halil Pasic >> Reviewed-by: David Hildenbrand >> Tested-by: Michael Mueller >> Tested-by: Farhan Ali >> Signed-off-by: Christian Borntraeger >> --- >> arch/s390/kvm/kvm-s390.c | 5 +++++ >> arch/s390/tools/gen_facilities.c | 2 ++ >> 2 files changed, 7 insertions(+), 0 deletions(-) >> >> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c >> index 286c2e0..f0b8e2a 100644 >> --- a/arch/s390/kvm/kvm-s390.c >> +++ b/arch/s390/kvm/kvm-s390.c >> @@ -371,6 +371,11 @@ static void kvm_s390_cpu_feat_init(void) >> >> if (MACHINE_HAS_ESOP) >> allow_cpu_feat(KVM_S390_VM_CPU_FEAT_ESOP); >> + >> + /* Check if AP instructions installed on host */ >> + if (ap_instructions_available()) >> + allow_cpu_feat(KVM_S390_VM_CPU_FEAT_AP); >> + >> /* >> * We need SIE support, ESOP (PROT_READ protection for gmap_shadow), >> * 64bit SCAO (SCA passthrough) and IDTE (for gmap_shadow unshadowing). >> diff --git a/arch/s390/tools/gen_facilities.c b/arch/s390/tools/gen_facilities.c >> index 0c85aed..fd788e0 100644 >> --- a/arch/s390/tools/gen_facilities.c >> +++ b/arch/s390/tools/gen_facilities.c >> @@ -106,6 +106,8 @@ struct facility_def { >> >> .name = "FACILITIES_KVM_CPUMODEL", >> .bits = (int[]){ >> + 12, /* AP Query Configuration Information */ >> + 15, /* AP Facilities Test */ >> 156, /* etoken facility */ >> -1 /* END */ >> } >> > > The fixup! patch below modifies this patch (25/26) to illustrate how > David's recommendation will be implemented for v11 of the series. It > is one of three fixup! patches (the other two are in responses to > 03/26 and 11/26) included to generate discussion in v10 rather than > waiting until v11 for comments. > > -----------------------------------8<----------------------------------- > > From: Tony Krowiak > Date: Thu, 20 Sep 2018 13:28:07 -0400 > Subject: [FIXUP v10] fixup!: KVM: s390: CPU model support for AP > virtualization > > --- > arch/s390/kvm/kvm-s390.c | 4 ---- > 1 files changed, 0 insertions(+), 4 deletions(-) > > diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c > index a3a7cd9..ff38251 100644 > --- a/arch/s390/kvm/kvm-s390.c > +++ b/arch/s390/kvm/kvm-s390.c > @@ -372,10 +372,6 @@ static void kvm_s390_cpu_feat_init(void) > if (MACHINE_HAS_ESOP) > allow_cpu_feat(KVM_S390_VM_CPU_FEAT_ESOP); > > - /* Check if AP instructions installed on host */ > - if (ap_instructions_available()) > - allow_cpu_feat(KVM_S390_VM_CPU_FEAT_AP); > - > /* > * We need SIE support, ESOP (PROT_READ protection for gmap_shadow), > * 64bit SCAO (SCA passthrough) and IDTE (for gmap_shadow unshadowing). > Yes, looks sane. -- Thanks, David / dhildenb