Re: [PATCH v3 13/17] x86/xen: enable Hygon support to Xen

From: Boris Ostrovsky
Date: Sun Aug 12 2018 - 09:27:23 EST


On 08/12/2018 04:55 AM, Juergen Gross wrote:
> On 11/08/18 16:34, Boris Ostrovsky wrote:
>> On 08/11/2018 09:29 AM, Pu Wen wrote:
>>
>>>
>>> bool pmu_msr_read(unsigned int msr, uint64_t *val, int *err)
>>> {
>>> - if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
>>> + if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD ||
>>> + boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) {
>>
>> 'if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)' please.
> Really? Xen supports Centaur, too.

VPMU doesn't --- hypervisor will not initialize it. Besides, the
existing code will steer non-AMD execution to Intel, which is not right
either.

I'll add a check to bail if VPMU is not initialized properly, we seem to
ignore xen_pmu_init() failures. Which, BTW, makes this patch rather
pointless until there is support for Hygon Xen.

-boris