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

[Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>]

Avi Kivity wrote:
> 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
>>   
>
>
Updated v2 should appear on the list soon reporting all gcc "error:" 
messages.

-- 

Grüsse / regards, 
Christian Ehrhardt
IBM Linux Technology Center, Open Virtualization