Re: [Qemu-devel] QEMU postcopy-test failing on ppc64

[Laurent Vivier]

On 15/11/2016 21:44, Laurent Vivier wrote:
> 
> 
> On 15/11/2016 21:39, Laurent Vivier wrote:
>>
>>
>> On 15/11/2016 20:00, Eric Blake wrote:
>>> On 11/15/2016 12:48 PM, Thomas Huth wrote:
>>>
>>>>> Even for Power, I'd prefer to keep KVM since the problem only happens with
>>>>> KVM PR which isn't the preferred way to do KVM on bare metal... until this
>>>>> get fixed, I'd rather suggest people to run make check with KVM HV.
>>>>
>>>> OK ... what do you think about a patch like this:
>>>>
>>>> diff --git a/tests/postcopy-test.c b/tests/postcopy-test.c
>>>> --- a/tests/postcopy-test.c
>>>> +++ b/tests/postcopy-test.c
>>>> @@ -380,17 +380,19 @@ static void test_migrate(void)
>>>>                                    " -incoming %s",
>>>>                                    tmpfs, bootpath, uri);
>>>>      } else if (strcmp(arch, "ppc64") == 0) {
>>>> +        const char *accel;
>>>>          init_bootfile_ppc(bootpath);
>>>> -        cmd_src = g_strdup_printf("-machine accel=kvm:tcg -m 256M"
>>>> +        accel = system("/sbin/lsmod | grep -q kvm_hv") ? "tcg" : 
>>>> "kvm:tcg";
>>>
>>> Unsafe use of system() (all I have to do is stick a counterfeit 'grep'
>>> earlier on my PATH to mess you up). Is there a safer way to grab that
>>> information without having to call out to the shell?
>>
>> I think trying to open "/dev/kvm" would be enough to know if kvm is
>> available or not.
> 
> OK, I've missed you want to check KVM HV only...

So, I think you can check for "/sys/module/kvm_hv"

Laurent