| Message ID | 1401970085-14493-3-git-send-email-aneesh.kumar@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 05.06.14 14:08, Aneesh Kumar K.V wrote: > We don't have SMT support yet, hence we should not find a doorbell > message generated > > Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> > --- > arch/powerpc/kvm/book3s_emulate.c | 18 ++++++++++++++++++ > 1 file changed, 18 insertions(+) > > diff --git a/arch/powerpc/kvm/book3s_emulate.c b/arch/powerpc/kvm/book3s_emulate.c > index 1bb16a59dcbc..d6c87d085182 100644 > --- a/arch/powerpc/kvm/book3s_emulate.c > +++ b/arch/powerpc/kvm/book3s_emulate.c > @@ -28,7 +28,9 @@ > #define OP_19_XOP_RFI 50 > > #define OP_31_XOP_MFMSR 83 > +#define OP_31_XOP_MSGSNDP 142 > #define OP_31_XOP_MTMSR 146 > +#define OP_31_XOP_MSGCLRP 174 > #define OP_31_XOP_MTMSRD 178 > #define OP_31_XOP_MTSR 210 > #define OP_31_XOP_MTSRIN 242 > @@ -303,6 +305,22 @@ int kvmppc_core_emulate_op_pr(struct kvm_run *run, struct kvm_vcpu *vcpu, > > break; > } > + case OP_31_XOP_MSGSNDP: > + { > + /* > + * PR KVM still don't support SMT mode. So we should still? > + * not see a MSGSNDP/MSGCLRP used with PR KVM > + */ > + pr_info("KVM: MSGSNDP used in non SMT case\n"); > + emulated = EMULATE_FAIL; What would happen on an HV guest with only 1 thread that MSGSNDs to thread 0? Would the guest get an illegal instruction trap, a self-interrupt or would this be a simple nop? Alex > + break; > + } > + case OP_31_XOP_MSGCLRP: > + { > + pr_info("KVM: MSGCLRP used in non SMT case\n"); > + emulated = EMULATE_FAIL; > + break; > + } > default: > emulated = EMULATE_FAIL; > } -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 05.06.14 14:21, Alexander Graf wrote: > > On 05.06.14 14:08, Aneesh Kumar K.V wrote: >> We don't have SMT support yet, hence we should not find a doorbell >> message generated >> >> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> >> --- >> arch/powerpc/kvm/book3s_emulate.c | 18 ++++++++++++++++++ >> 1 file changed, 18 insertions(+) >> >> diff --git a/arch/powerpc/kvm/book3s_emulate.c >> b/arch/powerpc/kvm/book3s_emulate.c >> index 1bb16a59dcbc..d6c87d085182 100644 >> --- a/arch/powerpc/kvm/book3s_emulate.c >> +++ b/arch/powerpc/kvm/book3s_emulate.c >> @@ -28,7 +28,9 @@ >> #define OP_19_XOP_RFI 50 >> #define OP_31_XOP_MFMSR 83 >> +#define OP_31_XOP_MSGSNDP 142 >> #define OP_31_XOP_MTMSR 146 >> +#define OP_31_XOP_MSGCLRP 174 >> #define OP_31_XOP_MTMSRD 178 >> #define OP_31_XOP_MTSR 210 >> #define OP_31_XOP_MTSRIN 242 >> @@ -303,6 +305,22 @@ int kvmppc_core_emulate_op_pr(struct kvm_run >> *run, struct kvm_vcpu *vcpu, >> break; >> } >> + case OP_31_XOP_MSGSNDP: >> + { >> + /* >> + * PR KVM still don't support SMT mode. So we should > > still? > >> + * not see a MSGSNDP/MSGCLRP used with PR KVM >> + */ >> + pr_info("KVM: MSGSNDP used in non SMT case\n"); >> + emulated = EMULATE_FAIL; > > What would happen on an HV guest with only 1 thread that MSGSNDs to > thread 0? Would the guest get an illegal instruction trap, a > self-interrupt or would this be a simple nop? What I'm trying to say here is that it's ok to treat it as illegal instructions, but then we don't need this patch :). Alex -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Alexander Graf <agraf@suse.de> writes: > On 05.06.14 14:21, Alexander Graf wrote: >> >> On 05.06.14 14:08, Aneesh Kumar K.V wrote: >>> We don't have SMT support yet, hence we should not find a doorbell >>> message generated >>> >>> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> >>> --- >>> arch/powerpc/kvm/book3s_emulate.c | 18 ++++++++++++++++++ >>> 1 file changed, 18 insertions(+) >>> >>> diff --git a/arch/powerpc/kvm/book3s_emulate.c >>> b/arch/powerpc/kvm/book3s_emulate.c >>> index 1bb16a59dcbc..d6c87d085182 100644 >>> --- a/arch/powerpc/kvm/book3s_emulate.c >>> +++ b/arch/powerpc/kvm/book3s_emulate.c >>> @@ -28,7 +28,9 @@ >>> #define OP_19_XOP_RFI 50 >>> #define OP_31_XOP_MFMSR 83 >>> +#define OP_31_XOP_MSGSNDP 142 >>> #define OP_31_XOP_MTMSR 146 >>> +#define OP_31_XOP_MSGCLRP 174 >>> #define OP_31_XOP_MTMSRD 178 >>> #define OP_31_XOP_MTSR 210 >>> #define OP_31_XOP_MTSRIN 242 >>> @@ -303,6 +305,22 @@ int kvmppc_core_emulate_op_pr(struct kvm_run >>> *run, struct kvm_vcpu *vcpu, >>> break; >>> } >>> + case OP_31_XOP_MSGSNDP: >>> + { >>> + /* >>> + * PR KVM still don't support SMT mode. So we should >> >> still? >> >>> + * not see a MSGSNDP/MSGCLRP used with PR KVM >>> + */ >>> + pr_info("KVM: MSGSNDP used in non SMT case\n"); >>> + emulated = EMULATE_FAIL; >> >> What would happen on an HV guest with only 1 thread that MSGSNDs to >> thread 0? Would the guest get an illegal instruction trap, a >> self-interrupt or would this be a simple nop? > > What I'm trying to say here is that it's ok to treat it as illegal > instructions, but then we don't need this patch :). > Agreed. I will verify whether it is treated as a nop. If so will send an updated patch. -aneesh -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Alexander Graf <agraf@suse.de> writes: > On 05.06.14 14:08, Aneesh Kumar K.V wrote: >> We don't have SMT support yet, hence we should not find a doorbell >> message generated >> >> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> >> --- >> arch/powerpc/kvm/book3s_emulate.c | 18 ++++++++++++++++++ >> 1 file changed, 18 insertions(+) >> >> diff --git a/arch/powerpc/kvm/book3s_emulate.c b/arch/powerpc/kvm/book3s_emulate.c >> index 1bb16a59dcbc..d6c87d085182 100644 >> --- a/arch/powerpc/kvm/book3s_emulate.c >> +++ b/arch/powerpc/kvm/book3s_emulate.c >> @@ -28,7 +28,9 @@ >> #define OP_19_XOP_RFI 50 >> >> #define OP_31_XOP_MFMSR 83 >> +#define OP_31_XOP_MSGSNDP 142 >> #define OP_31_XOP_MTMSR 146 >> +#define OP_31_XOP_MSGCLRP 174 >> #define OP_31_XOP_MTMSRD 178 >> #define OP_31_XOP_MTSR 210 >> #define OP_31_XOP_MTSRIN 242 >> @@ -303,6 +305,22 @@ int kvmppc_core_emulate_op_pr(struct kvm_run *run, struct kvm_vcpu *vcpu, >> >> break; >> } >> + case OP_31_XOP_MSGSNDP: >> + { >> + /* >> + * PR KVM still don't support SMT mode. So we should > > still? > >> + * not see a MSGSNDP/MSGCLRP used with PR KVM >> + */ >> + pr_info("KVM: MSGSNDP used in non SMT case\n"); >> + emulated = EMULATE_FAIL; > > What would happen on an HV guest with only 1 thread that MSGSNDs to > thread 0? Would the guest get an illegal instruction trap, a > self-interrupt or would this be a simple nop? > We do get a self-interrupt. I tried the below tag = mfspr(SPRN_TIR) & 0x7f; ppc_msgsnd(5, 0, tag); And that results in doorbell exception. That implies we will have to have full implementation of doorbell. You can drop patch 2 and 3 from this series. I will rework them. NOTE: This is not an issue for Linux guest, because we don't send ipi to self. But to complete the emulation of msgsndp we will need to emulate it properly. -aneesh -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/powerpc/kvm/book3s_emulate.c b/arch/powerpc/kvm/book3s_emulate.c index 1bb16a59dcbc..d6c87d085182 100644 --- a/arch/powerpc/kvm/book3s_emulate.c +++ b/arch/powerpc/kvm/book3s_emulate.c @@ -28,7 +28,9 @@ #define OP_19_XOP_RFI 50 #define OP_31_XOP_MFMSR 83 +#define OP_31_XOP_MSGSNDP 142 #define OP_31_XOP_MTMSR 146 +#define OP_31_XOP_MSGCLRP 174 #define OP_31_XOP_MTMSRD 178 #define OP_31_XOP_MTSR 210 #define OP_31_XOP_MTSRIN 242 @@ -303,6 +305,22 @@ int kvmppc_core_emulate_op_pr(struct kvm_run *run, struct kvm_vcpu *vcpu, break; } + case OP_31_XOP_MSGSNDP: + { + /* + * PR KVM still don't support SMT mode. So we should + * not see a MSGSNDP/MSGCLRP used with PR KVM + */ + pr_info("KVM: MSGSNDP used in non SMT case\n"); + emulated = EMULATE_FAIL; + break; + } + case OP_31_XOP_MSGCLRP: + { + pr_info("KVM: MSGCLRP used in non SMT case\n"); + emulated = EMULATE_FAIL; + break; + } default: emulated = EMULATE_FAIL; }
We don't have SMT support yet, hence we should not find a doorbell message generated Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> --- arch/powerpc/kvm/book3s_emulate.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+)