From: Christian Borntraeger borntraeger@de.ibm.com

[ Upstream commit 35b3fde6203b932b2b1a5b53b3d8808abc9c4f60 ]

The new firmware interfaces for branch prediction behaviour changes are transparently available for the guest. Nevertheless, there is new state attached that should be migrated and properly resetted. Provide a mechanism for handling reset, migration and VSIE.

Signed-off-by: Christian Borntraeger borntraeger@de.ibm.com Reviewed-by: David Hildenbrand david@redhat.com Reviewed-by: Cornelia Huck cohuck@redhat.com [Changed capability number to 152. - Radim] Signed-off-by: Radim Krčmář rkrcmar@redhat.com --- arch/s390/include/asm/kvm_host.h | 3 ++- arch/s390/include/uapi/asm/kvm.h | 3 +++ arch/s390/kvm/kvm-s390.c | 13 ++++++++++++- include/uapi/linux/kvm.h | 1 + 4 files changed, 18 insertions(+), 2 deletions(-)

Index: linux/arch/s390/include/asm/kvm_host.h =================================================================== --- linux.orig/arch/s390/include/asm/kvm_host.h +++ linux/arch/s390/include/asm/kvm_host.h @@ -136,7 +136,8 @@ struct kvm_s390_sie_block { __u16 ipa; /* 0x0056 */ __u32 ipb; /* 0x0058 */ __u32 scaoh; /* 0x005c */ - __u8 reserved60; /* 0x0060 */ +#define FPF_BPBC 0x20 + __u8 fpf; /* 0x0060 */ __u8 ecb; /* 0x0061 */ __u8 ecb2; /* 0x0062 */ #define ECB3_AES 0x04 Index: linux/arch/s390/include/uapi/asm/kvm.h =================================================================== --- linux.orig/arch/s390/include/uapi/asm/kvm.h +++ linux/arch/s390/include/uapi/asm/kvm.h @@ -151,6 +151,7 @@ struct kvm_guest_debug_arch { #define KVM_SYNC_ARCH0 (1UL << 4) #define KVM_SYNC_PFAULT (1UL << 5) #define KVM_SYNC_VRS (1UL << 6) +#define KVM_SYNC_BPBC (1UL << 10) /* definition of registers in kvm_run */ struct kvm_sync_regs { __u64 prefix; /* prefix register */ @@ -168,6 +169,8 @@ struct kvm_sync_regs { __u64 vrs[32][2]; /* vector registers */ __u8 reserved[512]; /* for future vector expansion */ __u32 fpc; /* only valid with vector registers */ + __u8 bpbc : 1; /* bp mode */ + __u8 reserved2 : 7; };

#define KVM_REG_S390_TODPR (KVM_REG_S390 | KVM_REG_SIZE_U32 | 0x1) Index: linux/arch/s390/kvm/kvm-s390.c =================================================================== --- linux.orig/arch/s390/kvm/kvm-s390.c +++ linux/arch/s390/kvm/kvm-s390.c @@ -257,6 +257,9 @@ int kvm_vm_ioctl_check_extension(struct case KVM_CAP_S390_VECTOR_REGISTERS: r = MACHINE_HAS_VX; break; + case KVM_CAP_S390_BPB: + r = test_facility(82); + break; default: r = 0; } @@ -1264,6 +1267,8 @@ int kvm_arch_vcpu_init(struct kvm_vcpu * KVM_SYNC_PFAULT; if (test_kvm_facility(vcpu->kvm, 129)) vcpu->run->kvm_valid_regs |= KVM_SYNC_VRS; + if (test_kvm_facility(vcpu->kvm, 82)) + vcpu->run->kvm_valid_regs |= KVM_SYNC_BPBC;

if (kvm_is_ucontrol(vcpu->kvm)) return __kvm_ucontrol_vcpu_init(vcpu); @@ -1327,6 +1332,7 @@ static void kvm_s390_vcpu_initial_reset( current->thread.fpu.fpc = 0; vcpu->arch.sie_block->gbea = 1; vcpu->arch.sie_block->pp = 0; + vcpu->arch.sie_block->fpf &= ~FPF_BPBC; vcpu->arch.pfault_token = KVM_S390_PFAULT_TOKEN_INVALID; kvm_clear_async_pf_completion_queue(vcpu); if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm)) @@ -2145,6 +2151,11 @@ static void sync_regs(struct kvm_vcpu *v 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_BPBC) && + test_kvm_facility(vcpu->kvm, 82)) { + vcpu->arch.sie_block->fpf &= ~FPF_BPBC; + vcpu->arch.sie_block->fpf |= kvm_run->s.regs.bpbc ? FPF_BPBC : 0; + } kvm_run->kvm_dirty_regs = 0; }

@@ -2162,6 +2173,7 @@ static void store_regs(struct kvm_vcpu * kvm_run->s.regs.pft = vcpu->arch.pfault_token; kvm_run->s.regs.pfs = vcpu->arch.pfault_select; kvm_run->s.regs.pfc = vcpu->arch.pfault_compare; + kvm_run->s.regs.bpbc = (vcpu->arch.sie_block->fpf & FPF_BPBC) == FPF_BPBC; }

int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) Index: linux/include/uapi/linux/kvm.h =================================================================== --- linux.orig/include/uapi/linux/kvm.h +++ linux/include/uapi/linux/kvm.h @@ -831,6 +831,7 @@ struct kvm_ppc_smmu_info { #define KVM_CAP_GUEST_DEBUG_HW_WPS 120 #define KVM_CAP_SPLIT_IRQCHIP 121 #define KVM_CAP_IOEVENTFD_ANY_LENGTH 122 +#define KVM_CAP_S390_BPB 152

#ifdef KVM_CAP_IRQ_ROUTING