Re: [PATCH v2 4/7] s390/physmem_info: query diag500(STORAGE LIMIT) to support QEMU/KVM memory devices

[David Hildenbrand <david@redhat.com>]

On 17.10.24 16:32, Alexander Gordeev wrote:
> On Thu, Oct 17, 2024 at 02:07:12PM +0200, David Hildenbrand wrote:
>> On 17.10.24 12:00, David Hildenbrand wrote:
>>> Well, DIAGNOSE 260 is z/VM only and DIAG 500 is KVM only. So there are
>>> currently not really any other reasonable ways besides SCLP.
>>
>> Correction: Staring at the code again, in detect_physmem_online_ranges()
>> we will indeed try:
>>
>> a) sclp_early_read_storage_info()
>> b) diag260()
> 
> So why care to call diag260() in case of DIAGNOSE 500? What about the below?
> 
> void detect_physmem_online_ranges(unsigned long max_physmem_end)
> {
> 	if (!sclp_early_read_storage_info()) {
> 		physmem_info.info_source = MEM_DETECT_SCLP_STOR_INFO;
> 	} else if (physmem_info.info_source == MEM_DETECT_DIAG500_STOR_LIMIT) {
> 		unsigned long online_end;
> 
> 		if (!sclp_early_get_memsize(&online_end)) {
> 			physmem_info.info_source = MEM_DETECT_SCLP_READ_INFO;
> 			add_physmem_online_range(0, online_end);
> 		}
> 	} else if (!diag260()) {
> 		physmem_info.info_source = MEM_DETECT_DIAG260;
> 	} else if (max_physmem_end) {
> 		add_physmem_online_range(0, max_physmem_end);
> 	}
> }

Works for me, thanks!

-- 
Cheers,

David / dhildenb