On Wed, Feb 24, 2010 at 03:17:53PM +0100, Jan Kiszka wrote: > Do not write nmi_pending, sipi_vector, and mpstate unless we at least go > through a reset. And TSC as well as KVM wallclocks should only be > written on full sync, otherwise we risk to drop some time on during > state read-modify-write. > > Signed-off-by: Jan Kiszka <jan.kiszka@xxxxxxxxxxx> > --- > kvm.h | 2 +- > qemu-kvm-x86.c | 2 +- > target-i386/kvm.c | 32 ++++++++++++++++++++------------ > target-i386/machine.c | 2 +- > 4 files changed, 23 insertions(+), 15 deletions(-) > > diff --git a/kvm.h b/kvm.h > index 3ec5b59..3ee307d 100644 > --- a/kvm.h > +++ b/kvm.h > @@ -44,7 +44,7 @@ int kvm_log_stop(target_phys_addr_t phys_addr, ram_addr_t size); > int kvm_has_sync_mmu(void); > int kvm_has_vcpu_events(void); > int kvm_has_robust_singlestep(void); > -int kvm_put_vcpu_events(CPUState *env); > +int kvm_put_vcpu_events(CPUState *env, int level); > int kvm_get_vcpu_events(CPUState *env); > > void kvm_cpu_register_phys_memory_client(void); > diff --git a/qemu-kvm-x86.c b/qemu-kvm-x86.c > index 4e6ae70..b0f9670 100644 > --- a/qemu-kvm-x86.c > +++ b/qemu-kvm-x86.c > @@ -1391,7 +1391,7 @@ void kvm_arch_push_nmi(void *opaque) > void kvm_arch_cpu_reset(CPUState *env) > { > kvm_arch_reset_vcpu(env); > - kvm_put_vcpu_events(env); > + kvm_put_vcpu_events(env, KVM_PUT_RESET_STATE); > kvm_reset_mpstate(env); > if (!cpu_is_bsp(env) && !kvm_irqchip_in_kernel()) { > env->interrupt_request &= ~CPU_INTERRUPT_HARD; > diff --git a/target-i386/kvm.c b/target-i386/kvm.c > index 5f0829b..f1f44d3 100644 > --- a/target-i386/kvm.c > +++ b/target-i386/kvm.c > @@ -541,7 +541,7 @@ static void kvm_msr_entry_set(struct kvm_msr_entry *entry, > entry->data = value; > } > > -static int kvm_put_msrs(CPUState *env) > +static int kvm_put_msrs(CPUState *env, int level) > { > struct { > struct kvm_msrs info; > @@ -555,7 +555,6 @@ static int kvm_put_msrs(CPUState *env) > kvm_msr_entry_set(&msrs[n++], MSR_IA32_SYSENTER_EIP, env->sysenter_eip); > if (kvm_has_msr_star(env)) > kvm_msr_entry_set(&msrs[n++], MSR_STAR, env->star); > - kvm_msr_entry_set(&msrs[n++], MSR_IA32_TSC, env->tsc); > kvm_msr_entry_set(&msrs[n++], MSR_VM_HSAVE_PA, env->vm_hsave); > #ifdef TARGET_X86_64 > /* FIXME if lm capable */ > @@ -564,8 +563,12 @@ static int kvm_put_msrs(CPUState *env) > kvm_msr_entry_set(&msrs[n++], MSR_FMASK, env->fmask); > kvm_msr_entry_set(&msrs[n++], MSR_LSTAR, env->lstar); > #endif > - kvm_msr_entry_set(&msrs[n++], MSR_KVM_SYSTEM_TIME, env->system_time_msr); > - kvm_msr_entry_set(&msrs[n++], MSR_KVM_WALL_CLOCK, env->wall_clock_msr); > + if (level == KVM_PUT_FULL_STATE) { > + kvm_msr_entry_set(&msrs[n++], MSR_IA32_TSC, env->tsc); > + kvm_msr_entry_set(&msrs[n++], MSR_KVM_SYSTEM_TIME, > + env->system_time_msr); > + kvm_msr_entry_set(&msrs[n++], MSR_KVM_WALL_CLOCK, env->wall_clock_msr); > + } > > msr_data.info.nmsrs = n; > > @@ -783,7 +786,7 @@ static int kvm_get_mp_state(CPUState *env) > } > #endif > > -int kvm_put_vcpu_events(CPUState *env) > +int kvm_put_vcpu_events(CPUState *env, int level) > { > #ifdef KVM_CAP_VCPU_EVENTS > struct kvm_vcpu_events events; > @@ -807,8 +810,11 @@ int kvm_put_vcpu_events(CPUState *env) > > events.sipi_vector = env->sipi_vector; > > - events.flags = > - KVM_VCPUEVENT_VALID_NMI_PENDING | KVM_VCPUEVENT_VALID_SIPI_VECTOR; > + events.flags = 0; > + if (level >= KVM_PUT_RESET_STATE) { > + events.flags |= > + KVM_VCPUEVENT_VALID_NMI_PENDING | KVM_VCPUEVENT_VALID_SIPI_VECTOR; > + } > > return kvm_vcpu_ioctl(env, KVM_SET_VCPU_EVENTS, &events); What is the reason for write-back of any vcpu-event state for RUNTIME case again? The debug workaround? -- 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