From: Collin Walling <walling@linux.ibm.com>
Date: Mon, 22 Jun 2020 11:46:36 -0400
Subject: s390/kvm: diagnose 0x318 sync and reset
Git-commit: 23a60f834406c8e3805328b630d09d5546b460c1
Patch-mainline: v5.9-rc1
References: jsc#SLE-13746
DIAGNOSE 0x318 (diag318) sets information regarding the environment
the VM is running in (Linux, z/VM, etc) and is observed via
firmware/service events.
This is a privileged s390x instruction that must be intercepted by
SIE. Userspace handles the instruction as well as migration. Data
is communicated via VCPU register synchronization.
The Control Program Name Code (CPNC) is stored in the SIE block. The
CPNC along with the Control Program Version Code (CPVC) are stored
in the kvm_vcpu_arch struct.
This data is reset on load normal and clear resets.
Signed-off-by: Collin Walling <walling@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200622154636.5499-3-walling@linux.ibm.com
[borntraeger@de.ibm.com: fix sync_reg position]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
[ ptesarik: Change KVM_CAP_S390_DIAG318 value to match final upstream. ]
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
arch/s390/include/asm/kvm_host.h | 4 +++-
arch/s390/include/uapi/asm/kvm.h | 7 +++++--
arch/s390/kvm/kvm-s390.c | 11 ++++++++++-
arch/s390/kvm/vsie.c | 1 +
include/uapi/linux/kvm.h | 1 +
5 files changed, 20 insertions(+), 4 deletions(-)
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -260,7 +260,8 @@ struct kvm_s390_sie_block {
__u32 scaol; /* 0x0064 */
__u8 sdf; /* 0x0068 */
__u8 epdx; /* 0x0069 */
- __u8 reserved6a[2]; /* 0x006a */
+ __u8 cpnc; /* 0x006a */
+ __u8 reserved6b; /* 0x006b */
__u32 todpr; /* 0x006c */
#define GISA_FORMAT1 0x00000001
__u32 gd; /* 0x0070 */
@@ -742,6 +743,7 @@ struct kvm_vcpu_arch {
bool gs_enabled;
bool skey_enabled;
struct kvm_s390_pv_vcpu pv;
+ union diag318_info diag318_info;
};
struct kvm_vm_stat {
--- a/arch/s390/include/uapi/asm/kvm.h
+++ b/arch/s390/include/uapi/asm/kvm.h
@@ -231,11 +231,13 @@ struct kvm_guest_debug_arch {
#define KVM_SYNC_GSCB (1UL << 9)
#define KVM_SYNC_BPBC (1UL << 10)
#define KVM_SYNC_ETOKEN (1UL << 11)
+#define KVM_SYNC_DIAG318 (1UL << 12)
#define KVM_SYNC_S390_VALID_FIELDS \
(KVM_SYNC_PREFIX | KVM_SYNC_GPRS | KVM_SYNC_ACRS | KVM_SYNC_CRS | \
KVM_SYNC_ARCH0 | KVM_SYNC_PFAULT | KVM_SYNC_VRS | KVM_SYNC_RICCB | \
- KVM_SYNC_FPRS | KVM_SYNC_GSCB | KVM_SYNC_BPBC | KVM_SYNC_ETOKEN)
+ KVM_SYNC_FPRS | KVM_SYNC_GSCB | KVM_SYNC_BPBC | KVM_SYNC_ETOKEN | \
+ KVM_SYNC_DIAG318)
/* length and alignment of the sdnx as a power of two */
#define SDNXC 8
@@ -264,7 +266,8 @@ struct kvm_sync_regs {
__u8 reserved2 : 7;
__u8 padding1[51]; /* riccb needs to be 64byte aligned */
__u8 riccb[64]; /* runtime instrumentation controls block */
- __u8 padding2[192]; /* sdnx needs to be 256byte aligned */
+ __u64 diag318; /* diagnose 0x318 info */
+ __u8 padding2[184]; /* sdnx needs to be 256byte aligned */
union {
__u8 sdnx[SDNXL]; /* state description annex */
struct {
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -539,6 +539,7 @@ int kvm_vm_ioctl_check_extension(struct
case KVM_CAP_S390_AIS:
case KVM_CAP_S390_AIS_MIGRATION:
case KVM_CAP_S390_VCPU_RESETS:
+ case KVM_CAP_S390_DIAG318:
r = 1;
break;
case KVM_CAP_S390_HPAGE_1M:
@@ -2961,7 +2962,8 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *
KVM_SYNC_ACRS |
KVM_SYNC_CRS |
KVM_SYNC_ARCH0 |
- KVM_SYNC_PFAULT;
+ KVM_SYNC_PFAULT |
+ KVM_SYNC_DIAG318;
kvm_s390_set_prefix(vcpu, 0);
if (test_kvm_facility(vcpu->kvm, 64))
vcpu->run->kvm_valid_regs |= KVM_SYNC_RICCB;
@@ -3569,6 +3571,7 @@ static void kvm_arch_vcpu_ioctl_initial_
vcpu->arch.sie_block->pp = 0;
vcpu->arch.sie_block->fpf &= ~FPF_BPBC;
vcpu->arch.sie_block->todpr = 0;
+ vcpu->arch.sie_block->cpnc = 0;
}
}
@@ -3586,6 +3589,7 @@ static void kvm_arch_vcpu_ioctl_clear_re
regs->etoken = 0;
regs->etoken_extension = 0;
+ regs->diag318 = 0;
}
int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
@@ -4204,6 +4208,10 @@ static void sync_regs_fmt2(struct kvm_vc
if (vcpu->arch.pfault_token == KVM_S390_PFAULT_TOKEN_INVALID)
kvm_clear_async_pf_completion_queue(vcpu);
}
+ if (kvm_run->kvm_dirty_regs & KVM_SYNC_DIAG318) {
+ vcpu->arch.diag318_info.val = kvm_run->s.regs.diag318;
+ vcpu->arch.sie_block->cpnc = vcpu->arch.diag318_info.cpnc;
+ }
/*
* If userspace sets the riccb (e.g. after migration) to a valid state,
* we should enable RI here instead of doing the lazy enablement.
@@ -4305,6 +4313,7 @@ static void store_regs_fmt2(struct kvm_v
kvm_run->s.regs.pp = vcpu->arch.sie_block->pp;
kvm_run->s.regs.gbea = vcpu->arch.sie_block->gbea;
kvm_run->s.regs.bpbc = (vcpu->arch.sie_block->fpf & FPF_BPBC) == FPF_BPBC;
+ kvm_run->s.regs.diag318 = vcpu->arch.diag318_info.val;
if (MACHINE_HAS_GS) {
__ctl_set_bit(2, 4);
if (vcpu->arch.gs_enabled)
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -548,6 +548,7 @@ static int shadow_scb(struct kvm_vcpu *v
scb_s->ecd |= scb_o->ecd & ECD_ETOKENF;
scb_s->hpid = HPID_VSIE;
+ scb_s->cpnc = scb_o->cpnc;
prepare_ibc(vcpu, vsie_page);
rc = shadow_crycb(vcpu, vsie_page);
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -1007,6 +1007,7 @@ struct kvm_ppc_resize_hpt {
#define KVM_CAP_HYPERV_DIRECT_TLBFLUSH 175
#define KVM_CAP_S390_VCPU_RESETS 179
#define KVM_CAP_S390_PROTECTED 180
+#define KVM_CAP_S390_DIAG318 186
#ifdef KVM_CAP_IRQ_ROUTING