On Thu, Sep 08, 2022 at 04:25:28PM -0700, isaku.yamahata@xxxxxxxxx wrote: >From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx> > >commit 0dd6a6edb012 ("KVM: Dont mark TSC unstable due to S4 suspend") made >use of kvm_arch_hardware_enable() callback to detect that TSC goes backward >due to S4 suspend. It has to check it only when resuming from S4. Not >every time virtualization hardware ennoblement. Move the logic to >kvm_arch_resume() callback. IIUC, kvm_arch_resume() is called on the first CPU waking up from suspension. But the detection was done on every CPU. Is it a problem (i.e., we fail to detect TSC goes backward on some CPUs)?