diff options
| -rw-r--r-- | Documentation/virtual/kvm/api.txt | 13 | ||||
| -rw-r--r-- | arch/s390/include/asm/kvm_host.h | 2 | ||||
| -rw-r--r-- | arch/s390/kvm/intercept.c | 3 | ||||
| -rw-r--r-- | arch/s390/kvm/kvm-s390.c | 26 | ||||
| -rw-r--r-- | include/uapi/linux/kvm.h | 1 |
5 files changed, 43 insertions, 2 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index c4d2fb0e28ded..299306db5d841 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -3857,6 +3857,19 @@ as a broadcast even in x2APIC mode in order to support physical x2APIC without interrupt remapping. This is undesirable in logical mode, where 0xff represents CPUs 0-7 in cluster 0. +7.8 KVM_CAP_S390_USER_INSTR0 + +Architectures: s390 +Parameters: none + +With this capability enabled, all illegal instructions 0x0000 (2 bytes) will +be intercepted and forwarded to user space. User space can use this +mechanism e.g. to realize 2-byte software breakpoints. The kernel will +not inject an operating exception for these instructions, user space has +to take care of that. + +This capability can be enabled dynamically even if VCPUs were already +created and are running. 8. Other capabilities. ---------------------- diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h index 946fc86202fda..183b01727de4e 100644 --- a/arch/s390/include/asm/kvm_host.h +++ b/arch/s390/include/asm/kvm_host.h @@ -43,6 +43,7 @@ /* s390-specific vcpu->requests bit members */ #define KVM_REQ_ENABLE_IBS 8 #define KVM_REQ_DISABLE_IBS 9 +#define KVM_REQ_ICPT_OPEREXC 10 #define SIGP_CTRL_C 0x80 #define SIGP_CTRL_SCN_MASK 0x3f @@ -666,6 +667,7 @@ struct kvm_arch{ int user_cpu_state_ctrl; int user_sigp; int user_stsi; + int user_instr0; struct s390_io_adapter *adapters[MAX_S390_IO_ADAPTERS]; wait_queue_head_t ipte_wq; int ipte_lock_count; diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c index 850be47c4cc93..7a2f1551bc395 100644 --- a/arch/s390/kvm/intercept.c +++ b/arch/s390/kvm/intercept.c @@ -359,6 +359,9 @@ static int handle_operexc(struct kvm_vcpu *vcpu) test_kvm_facility(vcpu->kvm, 74)) return handle_sthyi(vcpu); + if (vcpu->arch.sie_block->ipa == 0 && vcpu->kvm->arch.user_instr0) + return -EOPNOTSUPP; + return kvm_s390_inject_program_int(vcpu, PGM_OPERATION); } diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index d42428c117941..63ac7c1641a7b 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -364,6 +364,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) case KVM_CAP_S390_USER_STSI: case KVM_CAP_S390_SKEYS: case KVM_CAP_S390_IRQ_STATE: + case KVM_CAP_S390_USER_INSTR0: r = 1; break; case KVM_CAP_S390_MEM_OP: @@ -456,6 +457,16 @@ out: return r; } +static void icpt_operexc_on_all_vcpus(struct kvm *kvm) +{ + unsigned int i; + struct kvm_vcpu *vcpu; + + kvm_for_each_vcpu(i, vcpu, kvm) { + kvm_s390_sync_request(KVM_REQ_ICPT_OPEREXC, vcpu); + } +} + static int kvm_vm_ioctl_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap) { int r; @@ -507,6 +518,12 @@ static int kvm_vm_ioctl_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap) kvm->arch.user_stsi = 1; r = 0; break; + case KVM_CAP_S390_USER_INSTR0: + VM_EVENT(kvm, 3, "%s", "ENABLE: CAP_S390_USER_INSTR0"); + kvm->arch.user_instr0 = 1; + icpt_operexc_on_all_vcpus(kvm); + r = 0; + break; default: r = -EINVAL; break; @@ -1836,6 +1853,8 @@ void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) vcpu->arch.gmap = vcpu->kvm->arch.gmap; sca_add_vcpu(vcpu); } + if (test_kvm_facility(vcpu->kvm, 74) || vcpu->kvm->arch.user_instr0) + vcpu->arch.sie_block->ictl |= ICTL_OPEREXC; /* make vcpu_load load the right gmap on the first trigger */ vcpu->arch.enabled_gmap = vcpu->arch.gmap; } @@ -1923,8 +1942,6 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu) } vcpu->arch.sie_block->riccbd = (unsigned long) &vcpu->run->s.regs.riccb; vcpu->arch.sie_block->ictl |= ICTL_ISKE | ICTL_SSKE | ICTL_RRBE; - if (test_kvm_facility(vcpu->kvm, 74)) - vcpu->arch.sie_block->ictl |= ICTL_OPEREXC; if (vcpu->kvm->arch.use_cmma) { rc = kvm_s390_vcpu_setup_cmma(vcpu); @@ -2369,6 +2386,11 @@ retry: goto retry; } + if (kvm_check_request(KVM_REQ_ICPT_OPEREXC, vcpu)) { + vcpu->arch.sie_block->ictl |= ICTL_OPEREXC; + goto retry; + } + /* nothing to do, just clear the request */ clear_bit(KVM_REQ_UNHALT, &vcpu->requests); diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 4f8030e5b05d2..70941f4ab6d80 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -867,6 +867,7 @@ struct kvm_ppc_smmu_info { #define KVM_CAP_VCPU_ATTRIBUTES 127 #define KVM_CAP_MAX_VCPU_ID 128 #define KVM_CAP_X2APIC_API 129 +#define KVM_CAP_S390_USER_INSTR0 130 #ifdef KVM_CAP_IRQ_ROUTING |