| Message ID | 1519741693-17440-5-git-send-email-akrowiak@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 27.02.2018 15:28, Tony Krowiak wrote: > 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 the > AP facilities are installed on the KVM guest. This > feature will be enabled by the kernel only if the AP > facilities are installed on the linux host. This feature > must be specifically turned on for the KVM guest from > userspace to allow guest access to AP devices installed > on the linux host. > > 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. This facility > must not be set by userspace if the KVM_S390_VM_CPU_FEAT_AP > feature is not installed. > > 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. This facility > must not be set by userspace if the KVM_S390_VM_CPU_FEAT_AP > feature is not installed. > > Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> > Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com> > Signed-off-by: Tony Krowiak <akrowiak@linux.vnet.ibm.com> > --- > arch/s390/include/uapi/asm/kvm.h | 1 + > arch/s390/kvm/kvm-s390.c | 4 ++++ > arch/s390/tools/gen_facilities.c | 2 ++ > 3 files changed, 7 insertions(+), 0 deletions(-) > > diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h > index 4cdaa55..a580dec 100644 > --- a/arch/s390/include/uapi/asm/kvm.h > +++ b/arch/s390/include/uapi/asm/kvm.h > @@ -130,6 +130,7 @@ struct kvm_s390_vm_cpu_machine { > #define KVM_S390_VM_CPU_FEAT_PFMFI 11 > #define KVM_S390_VM_CPU_FEAT_SIGPIF 12 > #define KVM_S390_VM_CPU_FEAT_KSS 13 > +#define KVM_S390_VM_CPU_FEAT_AP 14 > struct kvm_s390_vm_cpu_feat { > __u64 feat[16]; > }; > diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c > index de1e299..c68ca86 100644 > --- a/arch/s390/kvm/kvm-s390.c > +++ b/arch/s390/kvm/kvm-s390.c > @@ -347,6 +347,10 @@ static void kvm_s390_cpu_feat_init(void) > > if (MACHINE_HAS_ESOP) > allow_cpu_feat(KVM_S390_VM_CPU_FEAT_ESOP); > + > + if (ap_instructions_installed()) /* AP instructions installed on host */ > + allow_cpu_feat(KVM_S390_VM_CPU_FEAT_AP); Don't we have a SIE specific AP feature? So is it true, that once we have AP instructions, we are allowed to use them for SIE? Isn't there a "AP interpretation facility" or anything like that? (that unlocks ECA_APIE) > + > /* > * 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 90a8c9e..a52290b 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 */ > -1 /* END */ > } > }, > So only if this feature is enabled, we later on allow to kvm_ap_enable_ie_mode, right? So basically, without this feature: 1. We will never set the execution control ECA_APIE. 2. The masks will always be 0. Which also results in VSIE never having masks set.
On 02/28/2018 10:48 AM, David Hildenbrand wrote: > On 27.02.2018 15:28, Tony Krowiak wrote: >> 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 the >> AP facilities are installed on the KVM guest. This >> feature will be enabled by the kernel only if the AP >> facilities are installed on the linux host. This feature >> must be specifically turned on for the KVM guest from >> userspace to allow guest access to AP devices installed >> on the linux host. >> >> 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. This facility >> must not be set by userspace if the KVM_S390_VM_CPU_FEAT_AP >> feature is not installed. >> >> 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. This facility >> must not be set by userspace if the KVM_S390_VM_CPU_FEAT_AP >> feature is not installed. >> >> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> >> Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com> >> Signed-off-by: Tony Krowiak <akrowiak@linux.vnet.ibm.com> >> --- >> arch/s390/include/uapi/asm/kvm.h | 1 + >> arch/s390/kvm/kvm-s390.c | 4 ++++ >> arch/s390/tools/gen_facilities.c | 2 ++ >> 3 files changed, 7 insertions(+), 0 deletions(-) >> >> diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h >> index 4cdaa55..a580dec 100644 >> --- a/arch/s390/include/uapi/asm/kvm.h >> +++ b/arch/s390/include/uapi/asm/kvm.h >> @@ -130,6 +130,7 @@ struct kvm_s390_vm_cpu_machine { >> #define KVM_S390_VM_CPU_FEAT_PFMFI 11 >> #define KVM_S390_VM_CPU_FEAT_SIGPIF 12 >> #define KVM_S390_VM_CPU_FEAT_KSS 13 >> +#define KVM_S390_VM_CPU_FEAT_AP 14 >> struct kvm_s390_vm_cpu_feat { >> __u64 feat[16]; >> }; >> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c >> index de1e299..c68ca86 100644 >> --- a/arch/s390/kvm/kvm-s390.c >> +++ b/arch/s390/kvm/kvm-s390.c >> @@ -347,6 +347,10 @@ static void kvm_s390_cpu_feat_init(void) >> >> if (MACHINE_HAS_ESOP) >> allow_cpu_feat(KVM_S390_VM_CPU_FEAT_ESOP); >> + >> + if (ap_instructions_installed()) /* AP instructions installed on host */ >> + allow_cpu_feat(KVM_S390_VM_CPU_FEAT_AP); > > Don't we have a SIE specific AP feature? So is it true, that once we > have AP instructions, we are allowed to use them for SIE? Isn't there a > "AP interpretation facility" or anything like that? (that unlocks ECA_APIE) This seems to be coupled to the AP facility and there is no facility or scp bit. AP is too old to have that (predates STFLE)
On 28.02.2018 12:40, Christian Borntraeger wrote: > > > On 02/28/2018 10:48 AM, David Hildenbrand wrote: >> On 27.02.2018 15:28, Tony Krowiak wrote: >>> 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 the >>> AP facilities are installed on the KVM guest. This >>> feature will be enabled by the kernel only if the AP >>> facilities are installed on the linux host. This feature >>> must be specifically turned on for the KVM guest from >>> userspace to allow guest access to AP devices installed >>> on the linux host. >>> >>> 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. This facility >>> must not be set by userspace if the KVM_S390_VM_CPU_FEAT_AP >>> feature is not installed. >>> >>> 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. This facility >>> must not be set by userspace if the KVM_S390_VM_CPU_FEAT_AP >>> feature is not installed. >>> >>> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> >>> Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com> >>> Signed-off-by: Tony Krowiak <akrowiak@linux.vnet.ibm.com> >>> --- >>> arch/s390/include/uapi/asm/kvm.h | 1 + >>> arch/s390/kvm/kvm-s390.c | 4 ++++ >>> arch/s390/tools/gen_facilities.c | 2 ++ >>> 3 files changed, 7 insertions(+), 0 deletions(-) >>> >>> diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h >>> index 4cdaa55..a580dec 100644 >>> --- a/arch/s390/include/uapi/asm/kvm.h >>> +++ b/arch/s390/include/uapi/asm/kvm.h >>> @@ -130,6 +130,7 @@ struct kvm_s390_vm_cpu_machine { >>> #define KVM_S390_VM_CPU_FEAT_PFMFI 11 >>> #define KVM_S390_VM_CPU_FEAT_SIGPIF 12 >>> #define KVM_S390_VM_CPU_FEAT_KSS 13 >>> +#define KVM_S390_VM_CPU_FEAT_AP 14 >>> struct kvm_s390_vm_cpu_feat { >>> __u64 feat[16]; >>> }; >>> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c >>> index de1e299..c68ca86 100644 >>> --- a/arch/s390/kvm/kvm-s390.c >>> +++ b/arch/s390/kvm/kvm-s390.c >>> @@ -347,6 +347,10 @@ static void kvm_s390_cpu_feat_init(void) >>> >>> if (MACHINE_HAS_ESOP) >>> allow_cpu_feat(KVM_S390_VM_CPU_FEAT_ESOP); >>> + >>> + if (ap_instructions_installed()) /* AP instructions installed on host */ >>> + allow_cpu_feat(KVM_S390_VM_CPU_FEAT_AP); >> >> Don't we have a SIE specific AP feature? So is it true, that once we >> have AP instructions, we are allowed to use them for SIE? Isn't there a >> "AP interpretation facility" or anything like that? (that unlocks ECA_APIE) > > This seems to be coupled to the AP facility and there is no facility or scp bit. > AP is too old to have that (predates STFLE) > Interesting, so we (I :) ) didn't implement vSIE support back then because we never indicated the AP facility (sensed by executing the instruction) to the guest. So ECA_APIE can be used when we sense the AP facility. Thanks!
On 02/28/2018 06:58 AM, David Hildenbrand wrote: > On 28.02.2018 12:40, Christian Borntraeger wrote: >> >> On 02/28/2018 10:48 AM, David Hildenbrand wrote: >>> On 27.02.2018 15:28, Tony Krowiak wrote: >>>> 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 the >>>> AP facilities are installed on the KVM guest. This >>>> feature will be enabled by the kernel only if the AP >>>> facilities are installed on the linux host. This feature >>>> must be specifically turned on for the KVM guest from >>>> userspace to allow guest access to AP devices installed >>>> on the linux host. >>>> >>>> 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. This facility >>>> must not be set by userspace if the KVM_S390_VM_CPU_FEAT_AP >>>> feature is not installed. >>>> >>>> 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. This facility >>>> must not be set by userspace if the KVM_S390_VM_CPU_FEAT_AP >>>> feature is not installed. >>>> >>>> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> >>>> Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com> >>>> Signed-off-by: Tony Krowiak <akrowiak@linux.vnet.ibm.com> >>>> --- >>>> arch/s390/include/uapi/asm/kvm.h | 1 + >>>> arch/s390/kvm/kvm-s390.c | 4 ++++ >>>> arch/s390/tools/gen_facilities.c | 2 ++ >>>> 3 files changed, 7 insertions(+), 0 deletions(-) >>>> >>>> diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h >>>> index 4cdaa55..a580dec 100644 >>>> --- a/arch/s390/include/uapi/asm/kvm.h >>>> +++ b/arch/s390/include/uapi/asm/kvm.h >>>> @@ -130,6 +130,7 @@ struct kvm_s390_vm_cpu_machine { >>>> #define KVM_S390_VM_CPU_FEAT_PFMFI 11 >>>> #define KVM_S390_VM_CPU_FEAT_SIGPIF 12 >>>> #define KVM_S390_VM_CPU_FEAT_KSS 13 >>>> +#define KVM_S390_VM_CPU_FEAT_AP 14 >>>> struct kvm_s390_vm_cpu_feat { >>>> __u64 feat[16]; >>>> }; >>>> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c >>>> index de1e299..c68ca86 100644 >>>> --- a/arch/s390/kvm/kvm-s390.c >>>> +++ b/arch/s390/kvm/kvm-s390.c >>>> @@ -347,6 +347,10 @@ static void kvm_s390_cpu_feat_init(void) >>>> >>>> if (MACHINE_HAS_ESOP) >>>> allow_cpu_feat(KVM_S390_VM_CPU_FEAT_ESOP); >>>> + >>>> + if (ap_instructions_installed()) /* AP instructions installed on host */ >>>> + allow_cpu_feat(KVM_S390_VM_CPU_FEAT_AP); >>> Don't we have a SIE specific AP feature? So is it true, that once we >>> have AP instructions, we are allowed to use them for SIE? Isn't there a >>> "AP interpretation facility" or anything like that? (that unlocks ECA_APIE) >> This seems to be coupled to the AP facility and there is no facility or scp bit. >> AP is too old to have that (predates STFLE) >> > Interesting, so we (I :) ) didn't implement vSIE support back then > because we never indicated the AP facility (sensed by executing the > instruction) to the guest. > > So ECA_APIE can be used when we sense the AP facility. Thanks! All true. >
diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h index 4cdaa55..a580dec 100644 --- a/arch/s390/include/uapi/asm/kvm.h +++ b/arch/s390/include/uapi/asm/kvm.h @@ -130,6 +130,7 @@ struct kvm_s390_vm_cpu_machine { #define KVM_S390_VM_CPU_FEAT_PFMFI 11 #define KVM_S390_VM_CPU_FEAT_SIGPIF 12 #define KVM_S390_VM_CPU_FEAT_KSS 13 +#define KVM_S390_VM_CPU_FEAT_AP 14 struct kvm_s390_vm_cpu_feat { __u64 feat[16]; }; diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index de1e299..c68ca86 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -347,6 +347,10 @@ static void kvm_s390_cpu_feat_init(void) if (MACHINE_HAS_ESOP) allow_cpu_feat(KVM_S390_VM_CPU_FEAT_ESOP); + + if (ap_instructions_installed()) /* AP instructions installed on host */ + 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 90a8c9e..a52290b 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 */ -1 /* END */ } },