On 11/15/19 10:36 AM, Thomas Huth wrote:
> On 24/10/2019 13.40, Janosch Frank wrote:
>> Indicate via register sync if the VM is in secure mode.
>>
>> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
>> ---
>>  arch/s390/include/uapi/asm/kvm.h | 5 ++++-
>>  arch/s390/kvm/kvm-s390.c         | 7 ++++++-
>>  2 files changed, 10 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h
>> index 436ec7636927..b44c02426c2e 100644
>> --- a/arch/s390/include/uapi/asm/kvm.h
>> +++ b/arch/s390/include/uapi/asm/kvm.h
>> @@ -231,11 +231,13 @@ struct kvm_guest_debug_arch {
>>  #define KVM_SYNC_GSCB   (1UL << 9)
>>  #define KVM_SYNC_BPBC   (1UL << 10)
>>  #define KVM_SYNC_ETOKEN (1UL << 11)
>> +#define KVM_SYNC_PV	(1UL << 12)
>>  
>>  #define KVM_SYNC_S390_VALID_FIELDS \
>>  	(KVM_SYNC_PREFIX | KVM_SYNC_GPRS | KVM_SYNC_ACRS | KVM_SYNC_CRS | \
>>  	 KVM_SYNC_ARCH0 | KVM_SYNC_PFAULT | KVM_SYNC_VRS | KVM_SYNC_RICCB | \
>> -	 KVM_SYNC_FPRS | KVM_SYNC_GSCB | KVM_SYNC_BPBC | KVM_SYNC_ETOKEN)
>> +	 KVM_SYNC_FPRS | KVM_SYNC_GSCB | KVM_SYNC_BPBC | KVM_SYNC_ETOKEN | \
>> +	 KVM_SYNC_PV)
>>  
>>  /* length and alignment of the sdnx as a power of two */
>>  #define SDNXC 8
>> @@ -261,6 +263,7 @@ struct kvm_sync_regs {
>>  	__u8  reserved[512];	/* for future vector expansion */
>>  	__u32 fpc;		/* valid on KVM_SYNC_VRS or KVM_SYNC_FPRS */
>>  	__u8 bpbc : 1;		/* bp mode */
>> +	__u8 pv : 1;		/* pv mode */
>>  	__u8 reserved2 : 7;
> 
> Don't you want to decrease the reserved2 bits to 6 ? ...

Ups

> 
>>  	__u8 padding1[51];	/* riccb needs to be 64byte aligned */
> 
> ... otherwise you might mess up the alignment here!
> 
>>  	__u8 riccb[64];		/* runtime instrumentation controls block */
>> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
>> index f623c64aeade..500972a1f742 100644
>> --- a/arch/s390/kvm/kvm-s390.c
>> +++ b/arch/s390/kvm/kvm-s390.c
>> @@ -2856,6 +2856,8 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
>>  		vcpu->run->kvm_valid_regs |= KVM_SYNC_GSCB;
>>  	if (test_kvm_facility(vcpu->kvm, 156))
>>  		vcpu->run->kvm_valid_regs |= KVM_SYNC_ETOKEN;
>> +	if (test_kvm_facility(vcpu->kvm, 161))
>> +		vcpu->run->kvm_valid_regs |= KVM_SYNC_PV;
>>  	/* fprs can be synchronized via vrs, even if the guest has no vx. With
>>  	 * MACHINE_HAS_VX, (load|store)_fpu_regs() will work with vrs format.
>>  	 */
>> @@ -4136,6 +4138,7 @@ static void store_regs_fmt2(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
>>  {
>>  	kvm_run->s.regs.gbea = vcpu->arch.sie_block->gbea;
>>  	kvm_run->s.regs.bpbc = (vcpu->arch.sie_block->fpf & FPF_BPBC) == FPF_BPBC;
>> +	kvm_run->s.regs.pv = 0;
>>  	if (MACHINE_HAS_GS) {
>>  		__ctl_set_bit(2, 4);
>>  		if (vcpu->arch.gs_enabled)
>> @@ -4172,8 +4175,10 @@ static void store_regs(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
>>  	/* Restore will be done lazily at return */
>>  	current->thread.fpu.fpc = vcpu->arch.host_fpregs.fpc;
>>  	current->thread.fpu.regs = vcpu->arch.host_fpregs.regs;
>> -	if (likely(!kvm_s390_pv_is_protected(vcpu->kvm)))
>> +	if (likely(!kvm_s390_pv_handle_cpu(vcpu)))
> 
> Why change the if-statement now? Should this maybe rather be squashed
> into the patch that introduced the if-statement?

That was part of a cleanup that should have been done in other patches.

> 
>>  		store_regs_fmt2(vcpu, kvm_run);
>> +	else
>> +		kvm_run->s.regs.pv = 1;
>>  }
>>  
>>  int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
>>
> 
>  Thomas
>