On 26/03/20 01:20, Wanpeng Li wrote: >> There are a few other occurrences of hrtimer_cancel, and all of them >> probably have a similar issue. What about adding a cancel_apic_timer > Other places are a little different, here we just disarm the timer, > other places we will restart the timer just after the disarm except > the vCPU reset (fixed in commit 95c065400a1 (KVM: VMX: Stop the > preemption timer during vCPU reset)), the restart will override > vmx->hv_deadline_tsc. What do you think? I can do it if introduce > cancel_apic_timer() is still better. At least start_apic_timer() would benefit from adding hrtimer_cancel(), removing it from kvm_set_lapic_tscdeadline_msr and kvm_lapic_reg_write. But you're right that it doesn't benefit from a cancel_apic_timer(), because ultimately they either update the preemption timer or cancel it in start_sw_timer. So I'll apply your patch and send a cleanup myself for start_apic_timer. Thanks, Paolo
