Re: [Qemu-devel] [Qemu-ppc] [PATCH] PPC: KVM: Don't tell the user about missing SPR syncs

[Alexey Kardashevskiy <aik@ozlabs.ru>]

On 02/04/2014 08:53 AM, Alexander Graf wrote:
> We sync a lot of SPRs automatically between KVM and QEMU now. Some
> of these only matter on newer hardware, some only matter on HV KVM.
> 
> With the current code runnign on my reasonably recent PR KVM kernel
> I get a lot of SPR synchronization warnings though:
> 
>   $ ./ppc64-softmmu/qemu-system-ppc64 -nographic -enable-kvm
>   Warning: Unable to set SPR 17 to KVM: Invalid argument
>   Warning: Unable to set SPR 29 to KVM: Invalid argument
>   Warning: Unable to set SPR 157 to KVM: Invalid argument
>   Warning: Unable to set SPR 308 to KVM: Invalid argument
>   Warning: Unable to set SPR 309 to KVM: Invalid argument
>   Warning: Unable to set SPR 318 to KVM: Invalid argument
>   Warning: Unable to set SPR 770 to KVM: Invalid argument
>   Warning: Unable to set SPR 945 to KVM: Invalid argument
>   Warning: Unable to set SPR 946 to KVM: Invalid argument
>   Warning: Unable to set SPR 1013 to KVM: Invalid argument
>   Warning: Unable to set SPR 17 to KVM: Invalid argument
>   Warning: Unable to set SPR 29 to KVM: Invalid argument
>   Warning: Unable to set SPR 157 to KVM: Invalid argument
>   Warning: Unable to set SPR 308 to KVM: Invalid argument
>   Warning: Unable to set SPR 309 to KVM: Invalid argument
>   Warning: Unable to set SPR 318 to KVM: Invalid argument
>   Warning: Unable to set SPR 770 to KVM: Invalid argument
>   Warning: Unable to set SPR 945 to KVM: Invalid argument
>   Warning: Unable to set SPR 946 to KVM: Invalid argument
>   Warning: Unable to set SPR 1013 to KVM: Invalid argument
> 
> Eventually we want to have something like a "verbose" flag that allows
> us to get these warnings when we see something goes wrong. But until
> then they do more harm than good exposed to casual users, so let's move
> them to debug prints.

Why are not these tracepoints? Then we would not need any "verbose" flag.


> 
> Signed-off-by: Alexander Graf <agraf@suse.de>
> ---
>  target-ppc/kvm.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/target-ppc/kvm.c b/target-ppc/kvm.c
> index 8f3f0bf..dce2156 100644
> --- a/target-ppc/kvm.c
> +++ b/target-ppc/kvm.c
> @@ -480,7 +480,7 @@ static void kvm_get_one_spr(CPUState *cs, uint64_t id, int spr)
>  
>      ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &reg);
>      if (ret != 0) {
> -        fprintf(stderr, "Warning: Unable to retrieve SPR %d from KVM: %s\n",
> +        DPRINTF("Warning: Unable to retrieve SPR %d from KVM: %s\n",
>                  spr, strerror(errno));
>      } else {
>          switch (id & KVM_REG_SIZE_MASK) {
> @@ -529,7 +529,7 @@ static void kvm_put_one_spr(CPUState *cs, uint64_t id, int spr)
>  
>      ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
>      if (ret != 0) {
> -        fprintf(stderr, "Warning: Unable to set SPR %d to KVM: %s\n",
> +        DPRINTF("Warning: Unable to set SPR %d to KVM: %s\n",
>                  spr, strerror(errno));
>      }
>  }
> 


-- 
Alexey