From cc92d6dea11cd43842e20cd05c066963de586417 Mon Sep 17 00:00:00 2001 From: Thomas Huth Date: Wed, 27 Nov 2013 11:47:10 +0100 Subject: [PATCH] KVM: s390: Reworked SIGP RESTART order When SIGP RESTART detected an illegal CPU address, there is no need to drop to userspace, we can return CC3 to the guest directly instead. Also renamed __sigp_restart() to sigp_check_callable() (since this is a better description of what the function is really doing) and moved a string specific to RESTART to the calling place instead, so that this function gets usable by other SIGP orders, too. Signed-off-by: Thomas Huth Reviewed-by: Cornelia Huck Signed-off-by: Cornelia Huck --- arch/s390/kvm/sigp.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) diff --git a/arch/s390/kvm/sigp.c b/arch/s390/kvm/sigp.c index eee1402349f2..509547d4fca1 100644 --- a/arch/s390/kvm/sigp.c +++ b/arch/s390/kvm/sigp.c @@ -363,7 +363,8 @@ static int __sigp_sense_running(struct kvm_vcpu *vcpu, u16 cpu_addr, return rc; } -static int __sigp_restart(struct kvm_vcpu *vcpu, u16 cpu_addr) +/* Test whether the destination CPU is available and not busy */ +static int sigp_check_callable(struct kvm_vcpu *vcpu, u16 cpu_addr) { struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int; struct kvm_s390_local_interrupt *li; @@ -382,9 +383,6 @@ static int __sigp_restart(struct kvm_vcpu *vcpu, u16 cpu_addr) spin_lock_bh(&li->lock); if (li->action_bits & ACTION_STOP_ON_STOP) rc = SIGP_CC_BUSY; - else - VCPU_EVENT(vcpu, 4, "sigp restart %x to handle userspace", - cpu_addr); spin_unlock_bh(&li->lock); out: spin_unlock(&fi->lock); @@ -459,10 +457,15 @@ int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu) break; case SIGP_RESTART: vcpu->stat.instruction_sigp_restart++; - rc = __sigp_restart(vcpu, cpu_addr); - if (rc == SIGP_CC_BUSY) - break; - /* user space must know about restart */ + rc = sigp_check_callable(vcpu, cpu_addr); + if (rc == SIGP_CC_ORDER_CODE_ACCEPTED) { + VCPU_EVENT(vcpu, 4, + "sigp restart %x to handle userspace", + cpu_addr); + /* user space must know about restart */ + rc = -EOPNOTSUPP; + } + break; default: return -EOPNOTSUPP; } -- 2.30.2