Re: [RESEND PATCH 5/6] KVM: x86/VMX: add kvm_vmx_reinject_nmi_irq() for NMI/IRQ reinjection

Peter Zijlstra
2022-11-24T09:46:37Z

On Wed, Nov 23, 2022 at 08:42:51PM +0000, Sean Christopherson wrote:
> arch/x86/kvm/kvm_cache_regs.h | 16 +++++------
> arch/x86/kvm/vmx/vmenter.S | 4 +--
> arch/x86/kvm/vmx/vmx.c | 51 ++++++++++++++++++-----------------
> arch/x86/kvm/vmx/vmx.h | 2 +-
> arch/x86/kvm/x86.h | 6 ++---
> 5 files changed, 41 insertions(+), 38 deletions(-)
>
> diff --git a/arch/x86/kvm/kvm_cache_regs.h b/arch/x86/kvm/kvm_cache_regs.h
> index c09174f73a34..af9bd0374915 100644
> --- a/arch/x86/kvm/kvm_cache_regs.h
> +++ b/arch/x86/kvm/kvm_cache_regs.h
> @@ -50,26 +50,26 @@ BUILD_KVM_GPR_ACCESSORS(r15, R15)
> * 1 0 register in vcpu->arch
> * 1 1 register in vcpu->arch, needs to be stored back
> */
> -static inline bool kvm_register_is_available(struct kvm_vcpu *vcpu,
> - enum kvm_reg reg)
> +static __always_inline bool kvm_register_is_available(struct kvm_vcpu *vcpu,
> + enum kvm_reg reg)
> {
> return test_bit(reg, (unsigned long *)&vcpu->arch.regs_avail);
> }
>
> -static inline bool kvm_register_is_dirty(struct kvm_vcpu *vcpu,
> - enum kvm_reg reg)
> +static __always_inline bool kvm_register_is_dirty(struct kvm_vcpu *vcpu,
> + enum kvm_reg reg)
> {
> return test_bit(reg, (unsigned long *)&vcpu->arch.regs_dirty);
> }
>
> -static inline void kvm_register_mark_available(struct kvm_vcpu *vcpu,
> - enum kvm_reg reg)
> +static __always_inline void kvm_register_mark_available(struct kvm_vcpu *vcpu,
> + enum kvm_reg reg)
> {
> __set_bit(reg, (unsigned long *)&vcpu->arch.regs_avail);
> }
>
> -static inline void kvm_register_mark_dirty(struct kvm_vcpu *vcpu,
> - enum kvm_reg reg)
> +static __always_inline void kvm_register_mark_dirty(struct kvm_vcpu *vcpu,
> + enum kvm_reg reg)
> {
> __set_bit(reg, (unsigned long *)&vcpu->arch.regs_avail);
> __set_bit(reg, (unsigned long *)&vcpu->arch.regs_dirty);

You'll have to consider include/asm-generic/bitops/instrumented-non-atomic.h
and friend, and the above should probably switch to using:

arch_test_bit(), arch___set_bit() resp.

to avoid the explicit instrumentation.