On 2011-04-18 10:03, Roedel, Joerg wrote: > On Sat, Apr 16, 2011 at 12:09:17PM -0400, Jan Kiszka wrote: >> This patch appears to cause troubles to Linux guests on TSC clocksource >> and APIC highres timer. The first boot after qemu start is always fine, >> but after a reboot the guest timer appears to fire incorrectly or even >> not at all. > > Hi Jan, > > can you please test if this patch fixes the problem? > > diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h > index bd57639..d7282ef 100644 > --- a/arch/x86/include/asm/kvm_host.h > +++ b/arch/x86/include/asm/kvm_host.h > @@ -391,7 +391,6 @@ struct kvm_vcpu_arch { > unsigned int hw_tsc_khz; > unsigned int time_offset; > struct page *time_page; > - u64 last_host_tsc; > u64 last_guest_tsc; > u64 last_kernel_ns; > u64 last_tsc_nsec; > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index 1d5a7f4..d8277aa 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -2146,7 +2146,7 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) > { > kvm_x86_ops->vcpu_put(vcpu); > kvm_put_guest_fpu(vcpu); > - vcpu->arch.last_host_tsc = native_read_tsc(); > + kvm_get_msr(vcpu, MSR_IA32_TSC, &vcpu->arch.last_guest_tsc); > } > > static int is_efer_nx(void) > Looks good, behaviour is now fine also after reboot. Thanks, Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html