diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 5833266407f521c711ec07441d580f1b87877f7d..587972ca12c54347b2cbcda4cb04bc97539cc4a1 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -988,7 +988,7 @@ for vm-wide capabilities. 4.38 KVM_GET_MP_STATE Capability: KVM_CAP_MP_STATE -Architectures: x86, ia64 +Architectures: x86, ia64, s390 Type: vcpu ioctl Parameters: struct kvm_mp_state (out) Returns: 0 on success; -1 on error @@ -1002,24 +1002,32 @@ uniprocessor guests). Possible values are: - - KVM_MP_STATE_RUNNABLE: the vcpu is currently running + - KVM_MP_STATE_RUNNABLE: the vcpu is currently running [x86, ia64] - KVM_MP_STATE_UNINITIALIZED: the vcpu is an application processor (AP) - which has not yet received an INIT signal + which has not yet received an INIT signal [x86, + ia64] - KVM_MP_STATE_INIT_RECEIVED: the vcpu has received an INIT signal, and is - now ready for a SIPI + now ready for a SIPI [x86, ia64] - KVM_MP_STATE_HALTED: the vcpu has executed a HLT instruction and - is waiting for an interrupt + is waiting for an interrupt [x86, ia64] - KVM_MP_STATE_SIPI_RECEIVED: the vcpu has just received a SIPI (vector - accessible via KVM_GET_VCPU_EVENTS) + accessible via KVM_GET_VCPU_EVENTS) [x86, ia64] + - KVM_MP_STATE_STOPPED: the vcpu is stopped [s390] + - KVM_MP_STATE_CHECK_STOP: the vcpu is in a special error state [s390] + - KVM_MP_STATE_OPERATING: the vcpu is operating (running or halted) + [s390] + - KVM_MP_STATE_LOAD: the vcpu is in a special load/startup state + [s390] -This ioctl is only useful after KVM_CREATE_IRQCHIP. Without an in-kernel -irqchip, the multiprocessing state must be maintained by userspace. +On x86 and ia64, this ioctl is only useful after KVM_CREATE_IRQCHIP. Without an +in-kernel irqchip, the multiprocessing state must be maintained by userspace on +these architectures. 4.39 KVM_SET_MP_STATE Capability: KVM_CAP_MP_STATE -Architectures: x86, ia64 +Architectures: x86, ia64, s390 Type: vcpu ioctl Parameters: struct kvm_mp_state (in) Returns: 0 on success; -1 on error @@ -1027,8 +1035,9 @@ Returns: 0 on success; -1 on error Sets the vcpu's current "multiprocessing state"; see KVM_GET_MP_STATE for arguments. -This ioctl is only useful after KVM_CREATE_IRQCHIP. Without an in-kernel -irqchip, the multiprocessing state must be maintained by userspace. +On x86 and ia64, this ioctl is only useful after KVM_CREATE_IRQCHIP. Without an +in-kernel irqchip, the multiprocessing state must be maintained by userspace on +these architectures. 4.40 KVM_SET_IDENTITY_MAP_ADDR diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h index 4181d7baabba99d810cbb53db383d65c12116409..c2ba0208a0e1446f127882ace9372eeaa8de912f 100644 --- a/arch/s390/include/asm/kvm_host.h +++ b/arch/s390/include/asm/kvm_host.h @@ -418,6 +418,7 @@ struct kvm_arch{ int css_support; int use_irqchip; int use_cmma; + int user_cpu_state_ctrl; struct s390_io_adapter *adapters[MAX_S390_IO_ADAPTERS]; wait_queue_head_t ipte_wq; spinlock_t start_stop_lock; diff --git a/arch/s390/kvm/diag.c b/arch/s390/kvm/diag.c index 0161675878a2483c7a3114ef6a82afa624a4ebcc..59bd8f991b986c56f39a8094d67f5dc21ac5f9ec 100644 --- a/arch/s390/kvm/diag.c +++ b/arch/s390/kvm/diag.c @@ -176,7 +176,8 @@ static int __diag_ipl_functions(struct kvm_vcpu *vcpu) return -EOPNOTSUPP; } - kvm_s390_vcpu_stop(vcpu); + if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm)) + kvm_s390_vcpu_stop(vcpu); vcpu->run->s390_reset_flags |= KVM_S390_RESET_SUBSYSTEM; vcpu->run->s390_reset_flags |= KVM_S390_RESET_IPL; vcpu->run->s390_reset_flags |= KVM_S390_RESET_CPU_INIT; diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c index a0b586c1913c18827b4a00e1b21f025d21c2515a..eaf46291d3619ab063f1162f54e82c3985db7d09 100644 --- a/arch/s390/kvm/intercept.c +++ b/arch/s390/kvm/intercept.c @@ -56,32 +56,26 @@ static int handle_noop(struct kvm_vcpu *vcpu) static int handle_stop(struct kvm_vcpu *vcpu) { int rc = 0; + unsigned int action_bits; vcpu->stat.exit_stop_request++; - spin_lock_bh(&vcpu->arch.local_int.lock); - trace_kvm_s390_stop_request(vcpu->arch.local_int.action_bits); - if (vcpu->arch.local_int.action_bits & ACTION_STOP_ON_STOP) { - kvm_s390_vcpu_stop(vcpu); - vcpu->arch.local_int.action_bits &= ~ACTION_STOP_ON_STOP; - VCPU_EVENT(vcpu, 3, "%s", "cpu stopped"); - rc = -EOPNOTSUPP; - } + action_bits = vcpu->arch.local_int.action_bits; - if (vcpu->arch.local_int.action_bits & ACTION_STORE_ON_STOP) { - vcpu->arch.local_int.action_bits &= ~ACTION_STORE_ON_STOP; - /* store status must be called unlocked. Since local_int.lock - * only protects local_int.* and not guest memory we can give - * up the lock here */ - spin_unlock_bh(&vcpu->arch.local_int.lock); + if (!(action_bits & ACTION_STOP_ON_STOP)) + return 0; + + if (action_bits & ACTION_STORE_ON_STOP) { rc = kvm_s390_vcpu_store_status(vcpu, KVM_S390_STORE_STATUS_NOADDR); - if (rc >= 0) - rc = -EOPNOTSUPP; - } else - spin_unlock_bh(&vcpu->arch.local_int.lock); - return rc; + if (rc) + return rc; + } + + if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm)) + kvm_s390_vcpu_stop(vcpu); + return -EOPNOTSUPP; } static int handle_validity(struct kvm_vcpu *vcpu) diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 2f3e14fe91a4882d0c5ed5599e1d6f0da2f750f0..fdf88f7a539c39fefa44a244225fe5422cc96a5b 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -167,6 +167,7 @@ int kvm_dev_ioctl_check_extension(long ext) case KVM_CAP_DEVICE_CTRL: case KVM_CAP_ENABLE_CAP_VM: case KVM_CAP_VM_ATTRIBUTES: + case KVM_CAP_MP_STATE: r = 1; break; case KVM_CAP_NR_VCPUS: @@ -595,7 +596,8 @@ static void kvm_s390_vcpu_initial_reset(struct kvm_vcpu *vcpu) vcpu->arch.sie_block->pp = 0; vcpu->arch.pfault_token = KVM_S390_PFAULT_TOKEN_INVALID; kvm_clear_async_pf_completion_queue(vcpu); - kvm_s390_vcpu_stop(vcpu); + if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm)) + kvm_s390_vcpu_stop(vcpu); kvm_s390_clear_local_irqs(vcpu); } @@ -926,7 +928,7 @@ static int kvm_arch_vcpu_ioctl_set_initial_psw(struct kvm_vcpu *vcpu, psw_t psw) { int rc = 0; - if (!(atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_STOPPED)) + if (!is_vcpu_stopped(vcpu)) rc = -EBUSY; else { vcpu->run->psw_mask = psw.mask; @@ -980,13 +982,34 @@ int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu, int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, struct kvm_mp_state *mp_state) { - return -EINVAL; /* not implemented yet */ + /* CHECK_STOP and LOAD are not supported yet */ + return is_vcpu_stopped(vcpu) ? KVM_MP_STATE_STOPPED : + KVM_MP_STATE_OPERATING; } int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, struct kvm_mp_state *mp_state) { - return -EINVAL; /* not implemented yet */ + int rc = 0; + + /* user space knows about this interface - let it control the state */ + vcpu->kvm->arch.user_cpu_state_ctrl = 1; + + switch (mp_state->mp_state) { + case KVM_MP_STATE_STOPPED: + kvm_s390_vcpu_stop(vcpu); + break; + case KVM_MP_STATE_OPERATING: + kvm_s390_vcpu_start(vcpu); + break; + case KVM_MP_STATE_LOAD: + case KVM_MP_STATE_CHECK_STOP: + /* fall through - CHECK_STOP and LOAD are not supported yet */ + default: + rc = -ENXIO; + } + + return rc; } bool kvm_s390_cmma_enabled(struct kvm *kvm) @@ -1284,7 +1307,13 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) if (vcpu->sigset_active) sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved); - kvm_s390_vcpu_start(vcpu); + if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm)) { + kvm_s390_vcpu_start(vcpu); + } else if (is_vcpu_stopped(vcpu)) { + pr_err_ratelimited("kvm-s390: can't run stopped vcpu %d\n", + vcpu->vcpu_id); + return -EINVAL; + } switch (kvm_run->exit_reason) { case KVM_EXIT_S390_SIEIC: @@ -1413,11 +1442,6 @@ int kvm_s390_vcpu_store_status(struct kvm_vcpu *vcpu, unsigned long addr) return kvm_s390_store_status_unloaded(vcpu, addr); } -static inline int is_vcpu_stopped(struct kvm_vcpu *vcpu) -{ - return atomic_read(&(vcpu)->arch.sie_block->cpuflags) & CPUSTAT_STOPPED; -} - static void __disable_ibs_on_vcpu(struct kvm_vcpu *vcpu) { kvm_check_request(KVM_REQ_ENABLE_IBS, vcpu); @@ -1494,7 +1518,15 @@ void kvm_s390_vcpu_stop(struct kvm_vcpu *vcpu) spin_lock_bh(&vcpu->kvm->arch.start_stop_lock); online_vcpus = atomic_read(&vcpu->kvm->online_vcpus); + /* Need to lock access to action_bits to avoid a SIGP race condition */ + spin_lock_bh(&vcpu->arch.local_int.lock); atomic_set_mask(CPUSTAT_STOPPED, &vcpu->arch.sie_block->cpuflags); + + /* SIGP STOP and SIGP STOP AND STORE STATUS has been fully processed */ + vcpu->arch.local_int.action_bits &= + ~(ACTION_STOP_ON_STOP | ACTION_STORE_ON_STOP); + spin_unlock_bh(&vcpu->arch.local_int.lock); + __disable_ibs_on_vcpu(vcpu); for (i = 0; i < online_vcpus; i++) { diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h index a8655ed31616746adc2fb2e7e454b22451e2f60e..33a0e4bed2a5f1ec83331147a218308a6679865c 100644 --- a/arch/s390/kvm/kvm-s390.h +++ b/arch/s390/kvm/kvm-s390.h @@ -45,9 +45,9 @@ do { \ d_args); \ } while (0) -static inline int __cpu_is_stopped(struct kvm_vcpu *vcpu) +static inline int is_vcpu_stopped(struct kvm_vcpu *vcpu) { - return atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_STOP_INT; + return atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_STOPPED; } static inline int kvm_is_ucontrol(struct kvm *kvm) @@ -129,6 +129,12 @@ static inline void kvm_s390_set_psw_cc(struct kvm_vcpu *vcpu, unsigned long cc) vcpu->arch.sie_block->gpsw.mask |= cc << 44; } +/* are cpu states controlled by user space */ +static inline int kvm_s390_user_cpu_state_ctrl(struct kvm *kvm) +{ + return kvm->arch.user_cpu_state_ctrl != 0; +} + int kvm_s390_handle_wait(struct kvm_vcpu *vcpu); enum hrtimer_restart kvm_s390_idle_wakeup(struct hrtimer *timer); void kvm_s390_tasklet(unsigned long parm); diff --git a/arch/s390/kvm/sigp.c b/arch/s390/kvm/sigp.c index 43079a48cc98d7858960e71f4d2f0b0b28ca8708..fd7fb5c5ef5dc0a85dc18b6a5dac50b038f01b6d 100644 --- a/arch/s390/kvm/sigp.c +++ b/arch/s390/kvm/sigp.c @@ -136,6 +136,11 @@ static int __inject_sigp_stop(struct kvm_s390_local_interrupt *li, int action) inti->type = KVM_S390_SIGP_STOP; spin_lock_bh(&li->lock); + if (li->action_bits & ACTION_STOP_ON_STOP) { + /* another SIGP STOP is pending */ + rc = SIGP_CC_BUSY; + goto out; + } if ((atomic_read(li->cpuflags) & CPUSTAT_STOPPED)) { kfree(inti); if ((action & ACTION_STORE_ON_STOP) != 0) @@ -144,8 +149,8 @@ static int __inject_sigp_stop(struct kvm_s390_local_interrupt *li, int action) } list_add_tail(&inti->list, &li->list); atomic_set(&li->active, 1); - atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags); li->action_bits |= action; + atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags); if (waitqueue_active(li->wq)) wake_up_interruptible(li->wq); out: diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index e11d8f170a62962c0bb62c9f5a28ffae88de08cf..9b744af871d74afb7f3e3b46b325ada5468cc4b5 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -399,13 +399,18 @@ struct kvm_vapic_addr { __u64 vapic_addr; }; -/* for KVM_SET_MPSTATE */ +/* for KVM_SET_MP_STATE */ +/* not all states are valid on all architectures */ #define KVM_MP_STATE_RUNNABLE 0 #define KVM_MP_STATE_UNINITIALIZED 1 #define KVM_MP_STATE_INIT_RECEIVED 2 #define KVM_MP_STATE_HALTED 3 #define KVM_MP_STATE_SIPI_RECEIVED 4 +#define KVM_MP_STATE_STOPPED 5 +#define KVM_MP_STATE_CHECK_STOP 6 +#define KVM_MP_STATE_OPERATING 7 +#define KVM_MP_STATE_LOAD 8 struct kvm_mp_state { __u32 mp_state;