Re: [Qemu-devel] [PATCH for-2.10] kvm: Print MSR information if KVM_SET_MSRS failed

[Dr. David Alan Gilbert]

* Eduardo Habkost (address@hidden) wrote:
> When a KVM_SET_MSRS ioctl() fails, it is difficult to find out
> which MSR caused the problem. Print an error message for
> debugging, before we trigger the (ret == cpu->kvm_msr_buf->nmsrs)
> assert.
> 
> Signed-off-by: Eduardo Habkost <address@hidden>
> ---
>  target/i386/kvm.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/target/i386/kvm.c b/target/i386/kvm.c
> index 887a81268f..3a874e4717 100644
> --- a/target/i386/kvm.c
> +++ b/target/i386/kvm.c
> @@ -1807,6 +1807,12 @@ static int kvm_put_msrs(X86CPU *cpu, int level)
>          return ret;
>      }
>  
> +    if (ret < cpu->kvm_msr_buf->nmsrs) {
> +        struct kvm_msr_entry *e = &cpu->kvm_msr_buf->entries[ret];
> +        error_report("error: failed to set MSR 0x%" PRIx32 " to 0x%" PRIx64,
> +                     (uint32_t)e->index, (uint64_t)e->data);
> +    }
> +

Yes, I'd thought about doing the same; had you considered adding it on the get
as well?

Reviewed-by: Dr. David Alan Gilbert <address@hidden>

Dave

>      assert(ret == cpu->kvm_msr_buf->nmsrs);
>      return 0;
>  }
> -- 
> 2.11.0.259.g40922b1
> 
--
Dr. David Alan Gilbert / address@hidden / Manchester, UK