diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index 73063ef5369432578a26dcb8fbffcf189e85aab2..dbd160f16cb0b6630dc25a0d793fb4bcfa0036a9 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -38,6 +38,12 @@ #include #endif +/* + * KVMPPC_INST_SW_BREAKPOINT is debug Instruction + * for supporting software breakpoint. + */ +#define KVMPPC_INST_SW_BREAKPOINT 0x00dddd00 + enum emulation_result { EMULATE_DONE, /* no further processing */ EMULATE_DO_MMIO, /* kvm_run filled with MMIO request */ diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c index f23b6a5530825703fc6ed8f3097c5a0c7b3d45e0..27d1b7041746433dad4b7053974d32d8c128a933 100644 --- a/arch/powerpc/kvm/book3s.c +++ b/arch/powerpc/kvm/book3s.c @@ -715,7 +715,8 @@ int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu, int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu, struct kvm_guest_debug *dbg) { - return -EINVAL; + vcpu->guest_debug = dbg->control; + return 0; } void kvmppc_decrementer_func(struct kvm_vcpu *vcpu) diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 529d10a7a36f025ce59ba1abbc73e9b7ce20e508..e63587d30b70819b15bb215ca858a7b722795a21 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -725,6 +725,30 @@ static int kvmppc_hcall_impl_hv(unsigned long cmd) return kvmppc_hcall_impl_hv_realmode(cmd); } +static int kvmppc_emulate_debug_inst(struct kvm_run *run, + struct kvm_vcpu *vcpu) +{ + u32 last_inst; + + if (kvmppc_get_last_inst(vcpu, INST_GENERIC, &last_inst) != + EMULATE_DONE) { + /* + * Fetch failed, so return to guest and + * try executing it again. + */ + return RESUME_GUEST; + } + + if (last_inst == KVMPPC_INST_SW_BREAKPOINT) { + run->exit_reason = KVM_EXIT_DEBUG; + run->debug.arch.address = kvmppc_get_pc(vcpu); + return RESUME_HOST; + } else { + kvmppc_core_queue_program(vcpu, SRR1_PROGILL); + return RESUME_GUEST; + } +} + static int kvmppc_handle_exit_hv(struct kvm_run *run, struct kvm_vcpu *vcpu, struct task_struct *tsk) { @@ -807,12 +831,18 @@ static int kvmppc_handle_exit_hv(struct kvm_run *run, struct kvm_vcpu *vcpu, break; /* * This occurs if the guest executes an illegal instruction. - * We just generate a program interrupt to the guest, since - * we don't emulate any guest instructions at this stage. + * If the guest debug is disabled, generate a program interrupt + * to the guest. If guest debug is enabled, we need to check + * whether the instruction is a software breakpoint instruction. + * Accordingly return to Guest or Host. */ case BOOK3S_INTERRUPT_H_EMUL_ASSIST: - kvmppc_core_queue_program(vcpu, SRR1_PROGILL); - r = RESUME_GUEST; + if (vcpu->guest_debug & KVM_GUESTDBG_USE_SW_BP) { + r = kvmppc_emulate_debug_inst(run, vcpu); + } else { + kvmppc_core_queue_program(vcpu, SRR1_PROGILL); + r = RESUME_GUEST; + } break; /* * This occurs if the guest (kernel or userspace), does something that @@ -924,6 +954,9 @@ static int kvmppc_get_one_reg_hv(struct kvm_vcpu *vcpu, u64 id, long int i; switch (id) { + case KVM_REG_PPC_DEBUG_INST: + *val = get_reg_val(id, KVMPPC_INST_SW_BREAKPOINT); + break; case KVM_REG_PPC_HIOR: *val = get_reg_val(id, 0); break; diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c index faffb27badd9de362465c6a8ea12052cb7ab53ef..6d7370890775c35fab424b1dd9c4441bdceaf619 100644 --- a/arch/powerpc/kvm/book3s_pr.c +++ b/arch/powerpc/kvm/book3s_pr.c @@ -1319,6 +1319,9 @@ static int kvmppc_get_one_reg_pr(struct kvm_vcpu *vcpu, u64 id, int r = 0; switch (id) { + case KVM_REG_PPC_DEBUG_INST: + *val = get_reg_val(id, KVMPPC_INST_SW_BREAKPOINT); + break; case KVM_REG_PPC_HIOR: *val = get_reg_val(id, to_book3s(vcpu)->hior); break; diff --git a/arch/powerpc/kvm/emulate.c b/arch/powerpc/kvm/emulate.c index e96b50d0bdab1f80f3374b35a7c9462a9fcc8a51..005222b580eaece3fcb1739b7810f04ae9c44a06 100644 --- a/arch/powerpc/kvm/emulate.c +++ b/arch/powerpc/kvm/emulate.c @@ -274,6 +274,21 @@ int kvmppc_emulate_instruction(struct kvm_run *run, struct kvm_vcpu *vcpu) } break; + case 0: + /* + * Instruction with primary opcode 0. Based on PowerISA + * these are illegal instructions. + */ + if (inst == KVMPPC_INST_SW_BREAKPOINT) { + run->exit_reason = KVM_EXIT_DEBUG; + run->debug.arch.address = kvmppc_get_pc(vcpu); + emulated = EMULATE_EXIT_USER; + advance = 0; + } else + emulated = EMULATE_FAIL; + + break; + default: emulated = EMULATE_FAIL; }