On 29.11.19 15:34, Janosch Frank wrote:
> On 11/29/19 3:24 PM, David Hildenbrand wrote:
>> On 29.11.19 15:20, Janosch Frank wrote:
>>> CPU resets for protected guests need to be done via Ultravisor
>>> calls. Hence we need a way to issue these calls for each reset.
>>>
>>> As we formerly had only one reset function and it was called for
>>> initial, as well as for the clear reset, we now need a new interface.
>>>
>>> Signed-off-by: Janosch Frank <fran...@linux.ibm.com>
>>> ---
>>> target/s390x/cpu.c | 14 ++++++++++++--
>>> target/s390x/kvm-stub.c | 10 +++++++++-
>>> target/s390x/kvm.c | 38 ++++++++++++++++++++++++++++++++------
>>> target/s390x/kvm_s390x.h | 4 +++-
>>> 4 files changed, 56 insertions(+), 10 deletions(-)
>>>
>>> diff --git a/target/s390x/cpu.c b/target/s390x/cpu.c
>>> index 829ce6ad54..906285888e 100644
>>> --- a/target/s390x/cpu.c
>>> +++ b/target/s390x/cpu.c
>>> @@ -139,8 +139,18 @@ static void s390_cpu_reset(CPUState *s, cpu_reset_type
>>> type)
>>> }
>>>
>>> /* Reset state inside the kernel that we cannot access yet from QEMU.
>>> */
>>> - if (kvm_enabled() && type != S390_CPU_RESET_NORMAL) {
>>> - kvm_s390_reset_vcpu(cpu);
>>> + if (kvm_enabled()) {
>>> + switch (type) {
>>> + case S390_CPU_RESET_CLEAR:
>>> + kvm_s390_reset_vcpu_clear(cpu);
>>> + break;
>>> + case S390_CPU_RESET_INITIAL:
>>> + kvm_s390_reset_vcpu_initial(cpu);
>>> + break;
>>> + case S390_CPU_RESET_NORMAL:
>>> + kvm_s390_reset_vcpu_normal(cpu);
>>> + break;
>>> + }
>>> }
>>> }
>>>
>>> diff --git a/target/s390x/kvm-stub.c b/target/s390x/kvm-stub.c
>>> index 5152e2bdf1..c4cd497f85 100644
>>> --- a/target/s390x/kvm-stub.c
>>> +++ b/target/s390x/kvm-stub.c
>>> @@ -83,7 +83,15 @@ void kvm_s390_cmma_reset(void)
>>> {
>>> }
>>>
>>> -void kvm_s390_reset_vcpu(S390CPU *cpu)
>>> +void kvm_s390_reset_vcpu_initial(S390CPU *cpu)
>>> +{
>>> +}
>>> +
>>> +void kvm_s390_reset_vcpu_clear(S390CPU *cpu)
>>> +{
>>> +}
>>> +
>>> +void kvm_s390_reset_vcpu_normal(S390CPU *cpu)
>>> {
>>> }
>>>
>>> diff --git a/target/s390x/kvm.c b/target/s390x/kvm.c
>>> index ad6e38c876..502fc71664 100644
>>> --- a/target/s390x/kvm.c
>>> +++ b/target/s390x/kvm.c
>>> @@ -151,6 +151,7 @@ static int cap_s390_irq;
>>> static int cap_ri;
>>> static int cap_gs;
>>> static int cap_hpage_1m;
>>> +static int cap_vcpu_resets;
>>>
>>> static int active_cmma;
>>>
>>> @@ -342,6 +343,7 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
>>> cap_async_pf = kvm_check_extension(s, KVM_CAP_ASYNC_PF);
>>> cap_mem_op = kvm_check_extension(s, KVM_CAP_S390_MEM_OP);
>>> cap_s390_irq = kvm_check_extension(s, KVM_CAP_S390_INJECT_IRQ);
>>> + cap_vcpu_resets = kvm_check_extension(s, KVM_CAP_S390_VCPU_RESETS);
>>>
>>> if (!kvm_check_extension(s, KVM_CAP_S390_GMAP)
>>> || !kvm_check_extension(s, KVM_CAP_S390_COW)) {
>>> @@ -403,20 +405,44 @@ int kvm_arch_destroy_vcpu(CPUState *cs)
>>> return 0;
>>> }
>>>
>>> -void kvm_s390_reset_vcpu(S390CPU *cpu)
>>> +static void kvm_s390_reset_vcpu(S390CPU *cpu, unsigned long type)
>>> {
>>> CPUState *cs = CPU(cpu);
>>>
>>> - /* The initial reset call is needed here to reset in-kernel
>>> - * vcpu data that we can't access directly from QEMU
>>> - * (i.e. with older kernels which don't support sync_regs/ONE_REG).
>>> - * Before this ioctl cpu_synchronize_state() is called in common kvm
>>> - * code (kvm-all) */
>>> + /*
>>> + * The reset call is needed here to reset in-kernel vcpu data that
>>> + * we can't access directly from QEMU (i.e. with older kernels
>>> + * which don't support sync_regs/ONE_REG). Before this ioctl
>>> + * cpu_synchronize_state() is called in common kvm code
>>> + * (kvm-all).
>>> + */
>>> + if (cap_vcpu_resets) {
>>> + if (kvm_vcpu_ioctl(cs, KVM_S390_VCPU_RESET, type)) {
>>> + error_report("CPU reset type %ld failed on CPU %i",
>>> + type, cs->cpu_index);
>>> + }
>>> + return;
>>> + }
>>> if (kvm_vcpu_ioctl(cs, KVM_S390_INITIAL_RESET, NULL)) {
>>> error_report("Initial CPU reset failed on CPU %i", cs->cpu_index);
>>> }
>>> }
>>
>> I think I commented this already: The issue is that without
>> cap_vcpu_requests, you would no do a KVM_S390_INITIAL_RESET for type ==
>> S390_CPU_RESET_NORMAL. You have to fence that.
>
> I did fix that, but not on this branch -_-
You can avoid that completely once you switch to two new separate ioctls ;)
--
Thanks,
David / dhildenb
