Re: [PATCH v2 06/30] KVM: remove realmode_lmsw function.

[Andre Przywara <andre.przywara@amd.com>]

Gleb Natapov wrote:
> Use (get|set)_cr callback to emulate lmsw inside emulator.
I see that vmx.c:handle_cr() is the only other user of kvm_lmsw(). If we 
fix this place similar like you did below, we could get rid of 
kvm_lmsw() entirely. But I am not sure whether it's OK to remove an 
exported symbol.

Regards,
Andre.

> 
> Signed-off-by: Gleb Natapov <gleb@redhat.com>
> ---
>  arch/x86/include/asm/kvm_host.h |    2 --
>  arch/x86/kvm/emulate.c          |    4 ++--
>  arch/x86/kvm/x86.c              |    7 -------
>  3 files changed, 2 insertions(+), 11 deletions(-)
> 
> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
> index e8e108a..1e15a0a 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -582,8 +582,6 @@ int emulate_instruction(struct kvm_vcpu *vcpu,
>  void kvm_report_emulation_failure(struct kvm_vcpu *cvpu, const char *context);
>  void realmode_lgdt(struct kvm_vcpu *vcpu, u16 size, unsigned long address);
>  void realmode_lidt(struct kvm_vcpu *vcpu, u16 size, unsigned long address);
> -void realmode_lmsw(struct kvm_vcpu *vcpu, unsigned long msw,
> -		   unsigned long *rflags);
>  
>  void kvm_enable_efer_bits(u64);
>  int kvm_get_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 *data);
> diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
> index 5b060e4..5e2fa61 100644
> --- a/arch/x86/kvm/emulate.c
> +++ b/arch/x86/kvm/emulate.c
> @@ -2486,8 +2486,8 @@ twobyte_insn:
>  			c->dst.val = ops->get_cr(0, ctxt->vcpu);
>  			break;
>  		case 6: /* lmsw */
> -			realmode_lmsw(ctxt->vcpu, (u16)c->src.val,
> -				      &ctxt->eflags);
> +			ops->set_cr(0, (ops->get_cr(0, ctxt->vcpu) & ~0x0ful) |
> +				    (c->src.val & 0x0f), ctxt->vcpu);
>  			c->dst.type = OP_NONE;
>  			break;
>  		case 7: /* invlpg*/
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index bf714df..b08f8a1 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -4045,13 +4045,6 @@ void realmode_lidt(struct kvm_vcpu *vcpu, u16 limit, unsigned long base)
>  	kvm_x86_ops->set_idt(vcpu, &dt);
>  }
>  
> -void realmode_lmsw(struct kvm_vcpu *vcpu, unsigned long msw,
> -		   unsigned long *rflags)
> -{
> -	kvm_lmsw(vcpu, msw);
> -	*rflags = kvm_get_rflags(vcpu);
> -}
> -
>  static int move_to_next_stateful_cpuid_entry(struct kvm_vcpu *vcpu, int i)
>  {
>  	struct kvm_cpuid_entry2 *e = &vcpu->arch.cpuid_entries[i];


-- 
Andre Przywara
AMD-OSRC (Dresden)
Tel: x29712