Re: [Qemu-devel] [PATCH uq/master] kvmclock: Ensure proper env->tsc value for kvmclock_current_nsec calculation

[Paolo Bonzini <pbonzini@redhat.com>]

Il 03/06/2014 18:34, Marcelo Tosatti ha scritto:
>
> Ensure proper env->tsc value for kvmclock_current_nsec calculation.
>
> Reported-by: Marcin Gibuła <m.gibula@beyond.pl>
> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
>
> diff --git a/hw/i386/kvm/clock.c b/hw/i386/kvm/clock.c
> index 6f4ed28a..bef2504 100644
> --- a/hw/i386/kvm/clock.c
> +++ b/hw/i386/kvm/clock.c
> @@ -17,6 +17,7 @@
>  #include "qemu/host-utils.h"
>  #include "sysemu/sysemu.h"
>  #include "sysemu/kvm.h"
> +#include "sysemu/cpus.h"
>  #include "hw/sysbus.h"
>  #include "hw/kvm/clock.h"
>
> @@ -65,6 +66,7 @@ static uint64_t kvmclock_current_nsec(KVMClockState *s)
>
>      cpu_physical_memory_read(kvmclock_struct_pa, &time, sizeof(time));
>
> +    assert(time.tsc_timestamp <= migration_tsc);
>      delta = migration_tsc - time.tsc_timestamp;
>      if (time.tsc_shift < 0) {
>          delta >>= -time.tsc_shift;
> @@ -123,6 +125,8 @@ static void kvmclock_vm_state_change(void *opaque, int running,
>          if (s->clock_valid) {
>              return;
>          }
> +
> +        cpu_synchronize_all_states();
>          ret = kvm_vm_ioctl(kvm_state, KVM_GET_CLOCK, &data);
>          if (ret < 0) {
>              fprintf(stderr, "KVM_GET_CLOCK failed: %s\n", strerror(ret));
>
>

This causes a hang during migration, so I'll revert the patch from 2.1. 
  Sorry.

Paolo