Re: [Qemu-devel] [PATCH] kvm: sync cpu state on internal error before dump

Andreas Färber
2013-08-24T17:28:53Z

Am 24.08.2013 12:37, schrieb Gleb Natapov:
> On Fri, Aug 23, 2013 at 02:41:13PM +0100, James Hogan wrote:
>> On 23/08/13 13:58, Gleb Natapov wrote:
>>> On Fri, Aug 23, 2013 at 01:26:00PM +0100, James Hogan wrote:
>>>> When a KVM internal error occurs QEMU dumps the CPU state, however it
>>>> doesn't synchronise the state from KVM first so the dumped state is out
>>>> of date. Add the synchronisation calls before the dump in both locations
>>>> (which is used depends on whether the arch says to stop or not).
>>>>
>>> x86_cpu_dump_state() calls cpu_synchronize_state() already.
>>
>> Ah yes, thanks. I hadn't noticed that.
>>
>> Out of the arches that support KVM only x86 and ppc call it. arm, mips
>> (qemu support not upstream yet), and s390 don't. s390 never seems to
>> emit that exit code, and arm only does so for unsupported exceptions
>> (which should never happen).
>>
>> I'll fix in mips_cpu_dump_state() instead.
>>
> Moving cpu_synchronize_state() up to cpu_dump_state() would be better.

Yes, please. I did not review the hooks themselves much, just avoided
global functions.

Andreas

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