From: Steven Rostedt <rostedt@xxxxxxxxxxx> Commit 92b5265d38f6a ("KVM: Depend on HIGH_RES_TIMERS") added a dependency to high resolution timers with the comment: KVM lapic timer and tsc deadline timer based on hrtimer, setting a leftmost node to rb tree and then do hrtimer reprogram. If hrtimer not configured as high resolution, hrtimer_enqueue_reprogram do nothing and then make kvm lapic timer and tsc deadline timer fail. That was back in 2012, where hrtimer_start_range_ns() would do the reprogramming with hrtimer_enqueue_reprogram(). But as that was a nop with high resolution timers disabled, this did not work. But a lot has changed in the last 12 years. For example, commit 49a2a07514a3a ("hrtimer: Kick lowres dynticks targets on timer enqueue") modifies __hrtimer_start_range_ns() to work with low res timers. There's been lots of other changes that make low res work. I added this change to my main server that runs all my VMs (my mail server, my web server, my ssh server) and disabled HIGH_RES_TIMERS and the system has been running just fine for over a month. ChromeOS has tested this before as well, and it hasn't seen any issues with running KVM with high res timers disabled. Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx> --- arch/x86/kvm/Kconfig | 1 - 1 file changed, 1 deletion(-) diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig index 472a1537b7a9..c65127e796a9 100644 --- a/arch/x86/kvm/Kconfig +++ b/arch/x86/kvm/Kconfig @@ -19,7 +19,6 @@ if VIRTUALIZATION config KVM tristate "Kernel-based Virtual Machine (KVM) support" - depends on HIGH_RES_TIMERS depends on X86_LOCAL_APIC select KVM_COMMON select KVM_GENERIC_MMU_NOTIFIER -- 2.43.0