Re: Does KVM support the P.A. Semi PA6T cpu?

[Alexander Graf <agraf@suse.de>]

On 30.05.14 14:42, Christian Zigotzky wrote:
> Am 30.05.14 14:21, schrieb Alexander Graf:
>>
>> On 30.05.14 13:39, Christian Zigotzky wrote:
>>> Hi Alex,
>>>
>>> Thank you for your answer. Here are the traces:
>>>
>>> http://www.xenosoft.de/trace_mol_mac_os_x_tiger.txt.tar.gz
>>> http://www.xenosoft.de/trace_mol_mac_os_x_jaguar.txt.tar.gz
>>
>> Looking at the Jaguar log, the guest seems to be stuck trying to map 
>> a page:
>>
>>              mol-4087  [001] ....   252.368002: kvm_exit: 
>> exitÚTA_STORAGE | pc=0x900074c4 | msr=0x4000d030 | dar=0xa000a434 | 
>> srr1=0x100000000000d032 | last_inst=0x912b0
>> 000
>>
>> If you look at the trace, you will see that this PC with the exact 
>> same DAR happens over and over again - every time the guest thinks 
>> it's mapped the page.
>>
>> I don't know why that's happening. Try to enable the debug prints (or 
>> convert them to trace points ;)) in the book3s_32 guest and book3s_64 
>> host emulation. Maybe that tells us something.
>>
>>
>> Alex
> Thanks Alex for your effort. How can I enable the debug prints?

This should do the trick. Output will be in dmesg:

diff --git a/arch/powerpc/kvm/book3s_32_mmu.c 
b/arch/powerpc/kvm/book3s_32_mmu.c
index 93503bb..939b14f 100644
--- a/arch/powerpc/kvm/book3s_32_mmu.c
+++ b/arch/powerpc/kvm/book3s_32_mmu.c
@@ -27,8 +27,8 @@
  #include <asm/kvm_ppc.h>
  #include <asm/kvm_book3s.h>

-/* #define DEBUG_MMU */
-/* #define DEBUG_MMU_PTE */
+#define DEBUG_MMU
+#define DEBUG_MMU_PTE
  /* #define DEBUG_MMU_PTE_IP 0xfff14c40 */

  #ifdef DEBUG_MMU


There's also always the chance that split real mode is the real culprit 
for breakage here. Have you verified that the same kernel source (KVM 
code) works on a PPC32 host with MOL?


Alex