From 0967fa1cd3769207cf74ae84144ce47fec65a317 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Tue, 16 Apr 2019 13:32:48 -0700 Subject: [PATCH] KVM: VMX: Skip delta_tsc shift-and-divide if the dividend is zero Ten percent of nothin' is... let me do the math here. Nothin' into nothin', carry the nothin'... Cc: Wanpeng Li Reviewed-by: Liran Alon Signed-off-by: Sean Christopherson Signed-off-by: Paolo Bonzini --- arch/x86/kvm/vmx/vmx.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 60e2f0afa4d6..d8f101b58ab8 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -7063,10 +7063,9 @@ static int vmx_set_hv_timer(struct kvm_vcpu *vcpu, u64 guest_deadline_tsc, /* Convert to host delta tsc if tsc scaling is enabled */ if (vcpu->arch.tsc_scaling_ratio != kvm_default_tsc_scaling_ratio && - u64_shl_div_u64(delta_tsc, + delta_tsc && u64_shl_div_u64(delta_tsc, kvm_tsc_scaling_ratio_frac_bits, - vcpu->arch.tsc_scaling_ratio, - &delta_tsc)) + vcpu->arch.tsc_scaling_ratio, &delta_tsc)) return -ERANGE; /* -- 2.30.2