Re: qemu-kvm loops after kernel udpate

From: Jiri Slaby
Date: Thu Sep 13 2012 - 14:32:08 EST


On 09/13/2012 11:59 AM, Avi Kivity wrote:
> On 09/12/2012 09:11 PM, Jiri Slaby wrote:
>> On 09/12/2012 10:18 AM, Avi Kivity wrote:
>>> On 09/12/2012 11:13 AM, Jiri Slaby wrote:
>>>>
>>>>> Please provide the output of vmxcap
>>>>> (http://goo.gl/c5lUO),
>>>>
>>>> Unrestricted guest no
>>>
>>> The big real mode fixes.
>>>
>>>
>>>>
>>>>> and a snapshot of kvm_stat while the guest is hung.
>>>>
>>>> kvm statistics
>>>>
>>>> exits 6778198 615942
>>>> host_state_reload 1988 187
>>>> irq_exits 1523 138
>>>> mmu_cache_miss 4 0
>>>> fpu_reload 1 0
>>>
>>> Please run this as root so we get the tracepoint based output; and press
>>> 'x' when it's running so we get more detailed output.
>>
>> kvm statistics
>>
>> kvm_exit 13798699 330708
>> kvm_entry 13799110 330708
>> kvm_page_fault 13793650 330604
>> kvm_exit(EXCEPTION_NMI) 6188458 330604
>> kvm_exit(EXTERNAL_INTERRUPT) 2169 105
>> kvm_exit(TPR_BELOW_THRESHOLD) 82 0
>> kvm_exit(IO_INSTRUCTION) 6 0
>
> Strange, it's unable to fault in the very first page.
>
> Please provide a trace as per http://www.linux-kvm.org/page/Tracing (but
> append -e kvmmmu to the command line).

Attached. Does it make sense? It wrote things like:
failed to read event print fmt for kvm_mmu_unsync_page
to the stderr.

thanks,
--
js
suse labs
version = 6
CPU 0 is empty
cpus=2
qemu-kvm-6170 [001] 457.811896: kvm_mmu_get_page: [FAILED TO PARSE] gfn=0 role=122882 root_count=0 unsync=0 created=1
qemu-kvm-6170 [001] 457.811899: kvm_mmu_get_page: [FAILED TO PARSE] gfn=262144 role=122882 root_count=0 unsync=0 created=1
qemu-kvm-6170 [001] 457.811900: kvm_mmu_get_page: [FAILED TO PARSE] gfn=524288 role=122882 root_count=0 unsync=0 created=1
qemu-kvm-6170 [001] 457.811902: kvm_mmu_get_page: [FAILED TO PARSE] gfn=786432 role=122882 root_count=0 unsync=0 created=1
qemu-kvm-6171 [001] 462.416705: kvm_mmu_prepare_zap_page: [FAILED TO PARSE] gfn=786432 role=122882 root_count=1 unsync=0
qemu-kvm-6171 [001] 462.416712: kvm_mmu_prepare_zap_page: [FAILED TO PARSE] gfn=524288 role=122882 root_count=1 unsync=0
qemu-kvm-6171 [001] 462.416715: kvm_mmu_prepare_zap_page: [FAILED TO PARSE] gfn=262144 role=122882 root_count=1 unsync=0
qemu-kvm-6171 [001] 462.416717: kvm_mmu_prepare_zap_page: [FAILED TO PARSE] gfn=0 role=122882 root_count=1 unsync=0
qemu-kvm-6171 [001] 462.485197: kvm_mmu_prepare_zap_page: [FAILED TO PARSE] gfn=0 role=253954 root_count=0 unsync=0
qemu-kvm-6171 [001] 462.485202: kvm_mmu_prepare_zap_page: [FAILED TO PARSE] gfn=262144 role=253954 root_count=0 unsync=0
qemu-kvm-6171 [001] 462.485205: kvm_mmu_prepare_zap_page: [FAILED TO PARSE] gfn=524288 role=253954 root_count=0 unsync=0
qemu-kvm-6171 [001] 462.485209: kvm_mmu_prepare_zap_page: [FAILED TO PARSE] gfn=786432 role=253954 root_count=0 unsync=0