10 files changed, 39 insertions, 10 deletions

diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index 552c319483c6..426614a882a9 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -122,6 +122,7 @@ struct esca_block {
 #define CPUSTAT_SLSR       0x00002000
 #define CPUSTAT_ZARCH      0x00000800
 #define CPUSTAT_MCDS       0x00000100
+#define CPUSTAT_KSS        0x00000200
 #define CPUSTAT_SM         0x00000080
 #define CPUSTAT_IBS        0x00000040
 #define CPUSTAT_GED2       0x00000010
@@ -185,6 +186,7 @@ struct kvm_s390_sie_block {
 #define ICPT_OPEREXC    0x2C
 #define ICPT_PARTEXEC   0x38
 #define ICPT_IOINST     0x40
+#define ICPT_KSS        0x5c
         __u8    icptcode;               /* 0x0050 */
         __u8    icptstatus;             /* 0x0051 */
         __u16   ihcpu;                  /* 0x0052 */
diff --git a/arch/s390/include/asm/sclp.h b/arch/s390/include/asm/sclp.h
index ace3bd315438..6f5167bc1928 100644
--- a/arch/s390/include/asm/sclp.h
+++ b/arch/s390/include/asm/sclp.h
@@ -75,6 +75,7 @@ struct sclp_info {
         unsigned char has_pfmfi : 1;
         unsigned char has_ibs : 1;
         unsigned char has_skey : 1;
+        unsigned char has_kss : 1;
         unsigned int ibc;
         unsigned int mtid;
         unsigned int mtid_cp;
diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h
index 2c9ad251fa33..bf9267930939 100644
--- a/arch/s390/include/uapi/asm/kvm.h
+++ b/arch/s390/include/uapi/asm/kvm.h
@@ -119,6 +119,7 @@ struct kvm_s390_vm_cpu_machine {
 #define KVM_S390_VM_CPU_FEAT_CMMA       10
 #define KVM_S390_VM_CPU_FEAT_PFMFI      11
 #define KVM_S390_VM_CPU_FEAT_SIGPIF     12
+#define KVM_S390_VM_CPU_FEAT_KSS        13
 struct kvm_s390_vm_cpu_feat {
         __u64 feat[16];
 };
diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c
index f5378f336127..a4752bf6b526 100644
--- a/arch/s390/kvm/intercept.c
+++ b/arch/s390/kvm/intercept.c
@@ -426,6 +426,9 @@ int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu)
         case ICPT_PARTEXEC:
                 rc = handle_partial_execution(vcpu);
                 break;
+        case ICPT_KSS:
+                rc = kvm_s390_skey_check_enable(vcpu);
+                break;
         default:
                 return -EOPNOTSUPP;
         }
diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index 482673e3436d..caf15c8a8948 100644
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -419,6 +419,8 @@ static int __write_machine_check(struct kvm_vcpu *vcpu,
         /* take care of lazy register loading */
         save_fpu_regs();
         save_access_regs(vcpu->run->s.regs.acrs);
+        if (MACHINE_HAS_GS && vcpu->arch.gs_enabled)
+                save_gs_cb(current->thread.gs_cb);
 
         /* Extended save area */
         rc = read_guest_lc(vcpu, __LC_MCESAD, &ext_sa_addr,
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 11b7d6638991..8771fef112a1 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -300,6 +300,8 @@ static void kvm_s390_cpu_feat_init(void)
                 allow_cpu_feat(KVM_S390_VM_CPU_FEAT_CEI);
         if (sclp.has_ibs)
                 allow_cpu_feat(KVM_S390_VM_CPU_FEAT_IBS);
+        if (sclp.has_kss)
+                allow_cpu_feat(KVM_S390_VM_CPU_FEAT_KSS);
         /*
          * KVM_S390_VM_CPU_FEAT_SKEY: Wrong shadow of PTE.I bits will make
          * all skey handling functions read/set the skey from the PGSTE
@@ -2034,7 +2036,11 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
         vcpu->arch.sie_block->sdnxo = ((unsigned long) &vcpu->run->s.regs.sdnx)
                                         | SDNXC;
         vcpu->arch.sie_block->riccbd = (unsigned long) &vcpu->run->s.regs.riccb;
-        vcpu->arch.sie_block->ictl |= ICTL_ISKE | ICTL_SSKE | ICTL_RRBE;
+
+        if (sclp.has_kss)
+                atomic_or(CPUSTAT_KSS, &vcpu->arch.sie_block->cpuflags);
+        else
+                vcpu->arch.sie_block->ictl |= ICTL_ISKE | ICTL_SSKE | ICTL_RRBE;
 
         if (vcpu->kvm->arch.use_cmma) {
                 rc = kvm_s390_vcpu_setup_cmma(vcpu);
diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
index 455124fe0647..55f5c8457d6d 100644
--- a/arch/s390/kvm/kvm-s390.h
+++ b/arch/s390/kvm/kvm-s390.h
@@ -254,6 +254,7 @@ int kvm_s390_handle_lpsw(struct kvm_vcpu *vcpu);
 int kvm_s390_handle_stctl(struct kvm_vcpu *vcpu);
 int kvm_s390_handle_lctl(struct kvm_vcpu *vcpu);
 int kvm_s390_handle_eb(struct kvm_vcpu *vcpu);
+int kvm_s390_skey_check_enable(struct kvm_vcpu *vcpu);
 
 /* implemented in vsie.c */
 int kvm_s390_handle_vsie(struct kvm_vcpu *vcpu);
diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
index 0ffe973535fa..c03106c428cf 100644
--- a/arch/s390/kvm/priv.c
+++ b/arch/s390/kvm/priv.c
@@ -198,18 +198,25 @@ static int handle_store_cpu_address(struct kvm_vcpu *vcpu)
         return 0;
 }
 
-static int __skey_check_enable(struct kvm_vcpu *vcpu)
+int kvm_s390_skey_check_enable(struct kvm_vcpu *vcpu)
 {
         int rc = 0;
+        struct kvm_s390_sie_block *sie_block = vcpu->arch.sie_block;
 
         trace_kvm_s390_skey_related_inst(vcpu);
-        if (!(vcpu->arch.sie_block->ictl & (ICTL_ISKE | ICTL_SSKE | ICTL_RRBE)))
+        if (!(sie_block->ictl & (ICTL_ISKE | ICTL_SSKE | ICTL_RRBE)) &&
+            !(atomic_read(&sie_block->cpuflags) & CPUSTAT_KSS))
                 return rc;
 
         rc = s390_enable_skey();
         VCPU_EVENT(vcpu, 3, "enabling storage keys for guest: %d", rc);
-        if (!rc)
-                vcpu->arch.sie_block->ictl &= ~(ICTL_ISKE | ICTL_SSKE | ICTL_RRBE);
+        if (!rc) {
+                if (atomic_read(&sie_block->cpuflags) & CPUSTAT_KSS)
+                        atomic_andnot(CPUSTAT_KSS, &sie_block->cpuflags);
+                else
+                        sie_block->ictl &= ~(ICTL_ISKE | ICTL_SSKE |
+                                             ICTL_RRBE);
+        }
         return rc;
 }
 
@@ -218,7 +225,7 @@ static int try_handle_skey(struct kvm_vcpu *vcpu)
         int rc;
 
         vcpu->stat.instruction_storage_key++;
-        rc = __skey_check_enable(vcpu);
+        rc = kvm_s390_skey_check_enable(vcpu);
         if (rc)
                 return rc;
         if (sclp.has_skey) {
@@ -916,7 +923,7 @@ static int handle_pfmf(struct kvm_vcpu *vcpu)
                 }
 
                 if (vcpu->run->s.regs.gprs[reg1] & PFMF_SK) {
-                        int rc = __skey_check_enable(vcpu);
+                        int rc = kvm_s390_skey_check_enable(vcpu);
 
                         if (rc)
                                 return rc;
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index 2fafc2be777f..4719ecb9ab42 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -117,6 +117,8 @@ static int prepare_cpuflags(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
                 newflags |= cpuflags & CPUSTAT_SM;
         if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_IBS))
                 newflags |= cpuflags & CPUSTAT_IBS;
+        if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_KSS))
+                newflags |= cpuflags & CPUSTAT_KSS;
 
         atomic_set(&scb_s->cpuflags, newflags);
         return 0;
@@ -289,7 +291,9 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
          * bits. Therefore we cannot provide interpretation and would later
          * have to provide own emulation handlers.
          */
-        scb_s->ictl |= ICTL_ISKE | ICTL_SSKE | ICTL_RRBE;
+        if (!(atomic_read(&scb_s->cpuflags) & CPUSTAT_KSS))
+                scb_s->ictl |= ICTL_ISKE | ICTL_SSKE | ICTL_RRBE;
+
         scb_s->icpua = scb_o->icpua;
 
         if (!(atomic_read(&scb_s->cpuflags) & CPUSTAT_SM))
@@ -627,7 +631,7 @@ static int pin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
                         rc = set_validity_icpt(scb_s, 0x10b0U);
                 if (rc)
                         goto unpin;
-                scb_s->sdnxo = hpa;
+                scb_s->sdnxo = hpa | sdnxc;
         }
         return 0;
 unpin:
diff --git a/drivers/s390/char/sclp_early.c b/drivers/s390/char/sclp_early.c
index 519ec1787117..efd84d1d178b 100644
--- a/drivers/s390/char/sclp_early.c
+++ b/drivers/s390/char/sclp_early.c
@@ -40,7 +40,8 @@ struct read_info_sccb {
         u8      fac85;                  /* 85 */
         u8      _pad_86[91 - 86];       /* 86-90 */
         u8      flags;                  /* 91 */
-        u8      _pad_92[99 - 92];       /* 92-98 */
+        u8      _pad_92[98 - 92];       /* 92-97 */
+        u8      fac98;                  /* 98 */
         u8      hamaxpow;               /* 99 */
         u32     rnsize2;                /* 100-103 */
         u64     rnmax2;                 /* 104-111 */
@@ -99,6 +100,7 @@ static void __init sclp_early_facilities_detect(struct read_info_sccb *sccb)
         sclp.has_pfmfi = !!(sccb->fac117 & 0x40);
         sclp.has_ibs = !!(sccb->fac117 & 0x20);
         sclp.has_hvs = !!(sccb->fac119 & 0x80);
+        sclp.has_kss = !!(sccb->fac98 & 0x01);
         if (sccb->fac85 & 0x02)
                 S390_lowcore.machine_flags |= MACHINE_FLAG_ESOP;
         sclp.rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;