On 8/12/21 11:38 AM, Janosch Frank wrote:
On 8/10/21 6:22 PM, Pierre Morel wrote:
We check the PTF instruction.
- We do not expect to support vertical polarization.
KVM does not support vertical polarization and we don't expect it to be
added in the future?
OK
- We do not expect the Modified Topology Change Report to be
pending or not at the moment the first PTF instruction with
PTF_CHECK function code is done as some code already did run
a polarization change may have occur.
ENOPARSE
OK I find another way to explain:
"
The Topology changes if the topology of the real CPUs backing the vCPUs
changes.
This can happen between the initialization of the VM and the start of
the guest.
As a consequence we can not expect the result of the first PTF instruction.
"
...
+ /*
+ * In the LPAR we can not assume the state of the polarizatiom
polarization
yes
+ * at this moment.
+ * Let's skip the tests for LPAR.
+ */
Any idea what happens on z/VM?
We don't necessarily need to support z/VM but we at least need to skip
like we do on lpar :-)
No, I do not know.
Then OK we skip the test for zVM too
Maybe also add a TODO, so we know we could improve the test?
+ if (machine_level < 3)
+ goto end;
+
Add comments:
We're always horizontally polarized in KVM.
OK
+ cc = ptf(PTF_REQ_HORIZONTAL, &rc);
+ report(cc == 2 && rc == PTF_ERR_ALRDY_POLARIZED,
+ "PTF horizontal already configured");
+
KVM doesn't support vertical polarization.
OK too
+ cc = ptf(PTF_REQ_VERTICAL, &rc);
+ report(cc == 2 && rc == PTF_ERR_NO_REASON,
+ "PTF vertical non possible");
s/non/not/
yes, seems I forgot to change this.
...
Thanks,
Pierre
--
Pierre Morel
IBM Lab Boeblingen
