Re: [RESEND v4 2/2] KVM: VMX: Enable bus lock VM exit

2020-10-25 Thread Chenyi Qiang
On 10/21/2020 6:19 AM, Sean Christopherson wrote: On Mon, Oct 12, 2020 at 11:35:42AM +0800, Chenyi Qiang wrote: @@ -6138,6 +6149,26 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath) return 0; } +static int vmx_handle_exit(struct kvm_vcpu *vcpu,

Re: [RESEND v4 2/2] KVM: VMX: Enable bus lock VM exit

2020-10-20 Thread Sean Christopherson
On Mon, Oct 12, 2020 at 11:35:42AM +0800, Chenyi Qiang wrote: > @@ -6138,6 +6149,26 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu, > fastpath_t exit_fastpath) > return 0; > } > > +static int vmx_handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath) > +{ > + int ret =

[RESEND v4 2/2] KVM: VMX: Enable bus lock VM exit

2020-10-11 Thread Chenyi Qiang
Virtual Machine can exploit bus locks to degrade the performance of system. Bus lock can be caused by split locked access to writeback(WB) memory or by using locks on uncacheable(UC) memory. The bus lock is typically >1000 cycles slower than an atomic operation within a cache line. It also