Enable the KVM capability KVM_CAP_PPC_FWNMI so that
the KVM causes guest exit with NMI as exit reason
when it encounters a machine check exception on the
address belonging to a guest. Without this capability
enabled, KVM redirects machine check exceptions to
guest's 0x200 vector.
Signed-off-by: Aravinda Prasad <aravinda@linux.vnet.ibm.com>
---
hw/ppc/spapr_rtas.c | 17 +++++++++++++++++
target/ppc/kvm.c | 2 ++
2 files changed, 19 insertions(+)
diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
index 2f3c47b..c2a361a 100644
--- a/hw/ppc/spapr_rtas.c
+++ b/hw/ppc/spapr_rtas.c
@@ -47,6 +47,8 @@
#include "trace.h"
#include "hw/ppc/fdt.h"
+extern int cap_fwnmi;
+
static void rtas_display_character(PowerPCCPU *cpu, sPAPRMachineState *spapr,
uint32_t token, uint32_t nargs,
target_ulong args,
@@ -354,7 +356,22 @@ static void rtas_ibm_nmi_register(PowerPCCPU *cpu,
target_ulong args,
uint32_t nret, target_ulong rets)
{
+ int ret;
+ CPUState *cs = CPU(cpu);
+
+ if (!cap_fwnmi) {
+ rtas_st(rets, 0, RTAS_OUT_NOT_SUPPORTED);
+ return;
+ }
+
spapr->guest_machine_check_addr = rtas_ld(args, 1);
+
+ ret = kvm_vcpu_enable_cap(cs, KVM_CAP_PPC_FWNMI, 0);
+ if (ret < 0) {
+ rtas_st(rets, 0, RTAS_OUT_HW_ERROR);
+ return;
+ }
+
rtas_st(rets, 0, RTAS_OUT_SUCCESS);
}
diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c
index 73f64ed..ca1ffa6 100644
--- a/target/ppc/kvm.c
+++ b/target/ppc/kvm.c
@@ -90,6 +90,7 @@ static int cap_htm; /* Hardware transactional memory support */
static int cap_mmu_radix;
static int cap_mmu_hash_v3;
static int cap_resize_hpt;
+int cap_fwnmi;
static uint32_t debug_inst_opcode;
@@ -147,6 +148,7 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
cap_mmu_radix = kvm_vm_check_extension(s, KVM_CAP_PPC_MMU_RADIX);
cap_mmu_hash_v3 = kvm_vm_check_extension(s, KVM_CAP_PPC_MMU_HASH_V3);
cap_resize_hpt = kvm_vm_check_extension(s, KVM_CAP_SPAPR_RESIZE_HPT);
+ cap_fwnmi = kvm_check_extension(s, KVM_CAP_PPC_FWNMI);
if (!cap_interrupt_level) {
fprintf(stderr, "KVM: Couldn't find level irq capability. Expect the "
On Wed, Aug 16, 2017 at 02:42:48PM +0530, Aravinda Prasad wrote:
> Enable the KVM capability KVM_CAP_PPC_FWNMI so that
> the KVM causes guest exit with NMI as exit reason
> when it encounters a machine check exception on the
> address belonging to a guest. Without this capability
> enabled, KVM redirects machine check exceptions to
> guest's 0x200 vector.
>
> Signed-off-by: Aravinda Prasad <aravinda@linux.vnet.ibm.com>
> ---
> hw/ppc/spapr_rtas.c | 17 +++++++++++++++++
> target/ppc/kvm.c | 2 ++
> 2 files changed, 19 insertions(+)
>
> diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
> index 2f3c47b..c2a361a 100644
> --- a/hw/ppc/spapr_rtas.c
> +++ b/hw/ppc/spapr_rtas.c
> @@ -47,6 +47,8 @@
> #include "trace.h"
> #include "hw/ppc/fdt.h"
>
> +extern int cap_fwnmi;
Ew. as the style checker will tell you, bare externs in .c files are
frowned upon. And the cap_* variables xertainly shouldn't be exported
from kvm.c.
> static void rtas_display_character(PowerPCCPU *cpu, sPAPRMachineState *spapr,
> uint32_t token, uint32_t nargs,
> target_ulong args,
> @@ -354,7 +356,22 @@ static void rtas_ibm_nmi_register(PowerPCCPU *cpu,
> target_ulong args,
> uint32_t nret, target_ulong rets)
> {
> + int ret;
> + CPUState *cs = CPU(cpu);
> +
> + if (!cap_fwnmi) {
> + rtas_st(rets, 0, RTAS_OUT_NOT_SUPPORTED);
> + return;
> + }
> +
> spapr->guest_machine_check_addr = rtas_ld(args, 1);
> +
> + ret = kvm_vcpu_enable_cap(cs, KVM_CAP_PPC_FWNMI, 0);
> + if (ret < 0) {
> + rtas_st(rets, 0, RTAS_OUT_HW_ERROR);
> + return;
> + }
> +
Congratulations, you broke build on an x86 host. Things that directly
call KVM need to go in kvm.c with suitable stubs for non-kvm builds.
> rtas_st(rets, 0, RTAS_OUT_SUCCESS);
> }
>
> diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c
> index 73f64ed..ca1ffa6 100644
> --- a/target/ppc/kvm.c
> +++ b/target/ppc/kvm.c
> @@ -90,6 +90,7 @@ static int cap_htm; /* Hardware transactional memory support */
> static int cap_mmu_radix;
> static int cap_mmu_hash_v3;
> static int cap_resize_hpt;
> +int cap_fwnmi;
>
> static uint32_t debug_inst_opcode;
>
> @@ -147,6 +148,7 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
> cap_mmu_radix = kvm_vm_check_extension(s, KVM_CAP_PPC_MMU_RADIX);
> cap_mmu_hash_v3 = kvm_vm_check_extension(s, KVM_CAP_PPC_MMU_HASH_V3);
> cap_resize_hpt = kvm_vm_check_extension(s, KVM_CAP_SPAPR_RESIZE_HPT);
> + cap_fwnmi = kvm_check_extension(s, KVM_CAP_PPC_FWNMI);
>
> if (!cap_interrupt_level) {
> fprintf(stderr, "KVM: Couldn't find level irq capability. Expect the "
>
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
On Thursday 17 August 2017 07:29 AM, David Gibson wrote:
> On Wed, Aug 16, 2017 at 02:42:48PM +0530, Aravinda Prasad wrote:
>> Enable the KVM capability KVM_CAP_PPC_FWNMI so that
>> the KVM causes guest exit with NMI as exit reason
>> when it encounters a machine check exception on the
>> address belonging to a guest. Without this capability
>> enabled, KVM redirects machine check exceptions to
>> guest's 0x200 vector.
>>
>> Signed-off-by: Aravinda Prasad <aravinda@linux.vnet.ibm.com>
>> ---
>> hw/ppc/spapr_rtas.c | 17 +++++++++++++++++
>> target/ppc/kvm.c | 2 ++
>> 2 files changed, 19 insertions(+)
>>
>> diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
>> index 2f3c47b..c2a361a 100644
>> --- a/hw/ppc/spapr_rtas.c
>> +++ b/hw/ppc/spapr_rtas.c
>> @@ -47,6 +47,8 @@
>> #include "trace.h"
>> #include "hw/ppc/fdt.h"
>>
>> +extern int cap_fwnmi;
>
> Ew. as the style checker will tell you, bare externs in .c files are
> frowned upon. And the cap_* variables xertainly shouldn't be exported
> from kvm.c.
Noted.
>
>> static void rtas_display_character(PowerPCCPU *cpu, sPAPRMachineState *spapr,
>> uint32_t token, uint32_t nargs,
>> target_ulong args,
>> @@ -354,7 +356,22 @@ static void rtas_ibm_nmi_register(PowerPCCPU *cpu,
>> target_ulong args,
>> uint32_t nret, target_ulong rets)
>> {
>> + int ret;
>> + CPUState *cs = CPU(cpu);
>> +
>> + if (!cap_fwnmi) {
>> + rtas_st(rets, 0, RTAS_OUT_NOT_SUPPORTED);
>> + return;
>> + }
>> +
>> spapr->guest_machine_check_addr = rtas_ld(args, 1);
>> +
>> + ret = kvm_vcpu_enable_cap(cs, KVM_CAP_PPC_FWNMI, 0);
>> + if (ret < 0) {
>> + rtas_st(rets, 0, RTAS_OUT_HW_ERROR);
>> + return;
>> + }
>> +
>
> Congratulations, you broke build on an x86 host. Things that directly
> call KVM need to go in kvm.c with suitable stubs for non-kvm builds.
Sure.
Regards,
Aravinda
>
>> rtas_st(rets, 0, RTAS_OUT_SUCCESS);
>> }
>>
>> diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c
>> index 73f64ed..ca1ffa6 100644
>> --- a/target/ppc/kvm.c
>> +++ b/target/ppc/kvm.c
>> @@ -90,6 +90,7 @@ static int cap_htm; /* Hardware transactional memory support */
>> static int cap_mmu_radix;
>> static int cap_mmu_hash_v3;
>> static int cap_resize_hpt;
>> +int cap_fwnmi;
>>
>> static uint32_t debug_inst_opcode;
>>
>> @@ -147,6 +148,7 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
>> cap_mmu_radix = kvm_vm_check_extension(s, KVM_CAP_PPC_MMU_RADIX);
>> cap_mmu_hash_v3 = kvm_vm_check_extension(s, KVM_CAP_PPC_MMU_HASH_V3);
>> cap_resize_hpt = kvm_vm_check_extension(s, KVM_CAP_SPAPR_RESIZE_HPT);
>> + cap_fwnmi = kvm_check_extension(s, KVM_CAP_PPC_FWNMI);
>>
>> if (!cap_interrupt_level) {
>> fprintf(stderr, "KVM: Couldn't find level irq capability. Expect the "
>>
>
--
Regards,
Aravinda
© 2016 - 2025 Red Hat, Inc.