Re: [PATCH] [PATCH] qemu: report issues causing the kvm probe to fail

[Avi Kivity <avi@redhat.com>]

Christian Ehrhardt wrote:
> I ran into the issue of a failign KVM Probe of the qemu configure script three
> times this week always needing "set -x", inserting an exit, masking the cleanup
> trap and compiling the c file by hand until I knew what the reason is. I think
> we could make easier for developers and end users.
> Therefore this patch keeps the qemu style configure output which is a list of
> "$Feature $Status", but extend the "no" result like "KVM Support no" with some
> more information.
>
> There might be a lot of things going wrong with that probe and I don't want
> to handle all of them, but if it is one of the known checks e.g. for
> KVM_API_VERSION then we could grep/awk that out and report it. The patch
> reports in case of a known case in the style
> "KVM support no - (Missing KVM capability KVM_CAP_DESTROY_MEMORY_REGION_WORKS)"
>
> In case more than one #error is triggered it creates a comma separated list in
> those brackets and in case it is something else than an #error it just reports
> plain old "no".
>
> diff --git a/qemu/configure b/qemu/configure
> --- a/qemu/configure
> +++ b/qemu/configure
> @@ -1037,12 +1037,14 @@ if test "$kvm" = "yes" ; then
>  if test "$kvm" = "yes" ; then
>      cat > $TMPC <<EOF
>  #include <linux/kvm.h>
> -#if !defined(KVM_API_VERSION) || \
> -    KVM_API_VERSION < 12 || \
> -    KVM_API_VERSION > 12 || \
> -    !defined(KVM_CAP_USER_MEMORY) || \
> -    !defined(KVM_CAP_SET_TSS_ADDR)
> +#if !defined(KVM_API_VERSION) || KVM_API_VERSION < 12 || KVM_API_VERSION > 12
>  #error Invalid KVM version
>   

You might refine this a bit:  if KVM_API_VERSION is not defined, most 
likely linux/kvm.h could not be found, so you might as well report that.

> +#endif
>   


-- 
error compiling committee.c: too many arguments to function