Re: [PATCH] KVM: PPC: Book3S HV: XIVE: introduce a KVM device lock

["Cédric Le Goater" <clg@kaod.org>]

On 31/05/2019 08:35, Paul Mackerras wrote:
> On Fri, May 24, 2019 at 03:20:30PM +0200, Cédric Le Goater wrote:
>> The XICS-on-XIVE KVM device needs to allocate XIVE event queues when a
>> priority is used by the OS. This is referred as EQ provisioning and it
>> is done under the hood when :
>>
>>   1. a CPU is hot-plugged in the VM
>>   2. the "set-xive" is called at VM startup
>>   3. sources are restored at VM restore
>>
>> The kvm->lock mutex is used to protect the different XIVE structures
>> being modified but in some contextes, kvm->lock is taken under the
>> vcpu->mutex which is a forbidden sequence by KVM.
>>
>> Introduce a new mutex 'lock' for the KVM devices for them to
>> synchronize accesses to the XIVE device structures.
>>
>> Signed-off-by: Cédric Le Goater <clg@kaod.org>
> 
> Thanks, patch applied to my kvm-ppc-fixes branch (with the headline
> "KVM: PPC: Book3S HV: XIVE: Introduce a new mutex for the XIVE
> device").

Yes. That's a better tittle. Thanks for doing so.

C.