Re: [kvm-unit-tests PATCH v3 11/17] powerpc/ppc64: add hcall support and putchar

[Thomas Huth <thuth@redhat.com>]

On 15.02.2016 09:54, Andrew Jones wrote:
> On Mon, Feb 15, 2016 at 10:29:54AM +1100, David Gibson wrote:
>> On Sat, Feb 13, 2016 at 05:28:24PM +0100, Andrew Jones wrote:
>>> +bool hcall_have_broken_sc1(void)
>>> +{
>>> +	register unsigned long r3 asm("r3") = H_SET_DABR;
>>> +	register unsigned long r4 asm("r4") = 0;
>>> +
>>> +	asm volatile("sc 1"
>>> +	: "=r" (r3)
>>> +	: "r" (r3), "r" (r4)
>>> +	: "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12");
>>> +
>>> +	return !(r3 = H_SUCCESS || r3 = (unsigned long)H_HARDWARE);
>>
>> It might be safer to explicitly check for H_PRIVILEGE, which is what
>> you'll get in the case of a broken sc 1 under nested virtualization.
>> That way you won't get false positives if H_SET_DABR ever gets any new
>> error codes it can return.
> 
> Will do. Thanks. Should we consider a SLOF patch too? (As I stole this
> condition from there, see check_broken_sc1 in lib/libhvcall/brokensc1.c)

Yes, I think it should be fixed there, too.

 Thomas