Re: [Qemu-devel] [PATCH 1/1] virtio-scsi-ccw: use ioeventfd even when KVM is disabled

[QingFeng Hao <haoqf@linux.vnet.ibm.com>]

在 2017/7/3 15:41, Christian Borntraeger 写道:
> On 07/03/2017 09:38 AM, QingFeng Hao wrote:
>> Do not check kvm_eventfds_enabled() when KVM is disabled since it
>> always returns 0.  Since commit 8c56c1a592b5092d91da8d8943c17777d6462a6f
>> ("memory: emulate ioeventfd") it has been possible to use ioeventfds in
>> qtest or TCG mode.
>>
>> This patch makes -device virtio-scsi-ccw,iothread=iothread0 work even
>> when KVM is disabled.
>>
>> I have tested that virtio-scsi-ccw works under tcg both with and without
>> iothread.
>>
>> This patch fixes qemu-iotests 068, which was accidentally merged early
>> despite the dependency on ioeventfd.
>>
>> Signed-off-by: QingFeng Hao <haoqf@linux.vnet.ibm.com>
>> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
> cut'n'paste mistake of adding Stefans signoff?
>
> Otherwise it looks good.
I just want to mark that this patch is related with the former one from 
Stefan.
Is that ok to add this sign-off? thanks!
>> ---
>>   hw/s390x/virtio-ccw.c | 2 +-
>>   target/s390x/kvm.c    | 3 +++
>>   2 files changed, 4 insertions(+), 1 deletion(-)
>>
>> diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c
>> index 90d37cb9ff..35896eb007 100644
>> --- a/hw/s390x/virtio-ccw.c
>> +++ b/hw/s390x/virtio-ccw.c
>> @@ -711,7 +711,7 @@ static void virtio_ccw_device_realize(VirtioCcwDevice *dev, Error **errp)
>>           sch->cssid, sch->ssid, sch->schid, sch->devno,
>>           ccw_dev->devno.valid ? "user-configured" : "auto-configured");
>>
>> -    if (!kvm_eventfds_enabled()) {
>> +    if (kvm_enabled() && !kvm_eventfds_enabled()) {
>>           dev->flags &= ~VIRTIO_CCW_FLAG_USE_IOEVENTFD;
>>       }
>>
>> diff --git a/target/s390x/kvm.c b/target/s390x/kvm.c
>> index a3d00196f4..c37f9c3b9e 100644
>> --- a/target/s390x/kvm.c
>> +++ b/target/s390x/kvm.c
>> @@ -2220,6 +2220,9 @@ int kvm_s390_assign_subch_ioeventfd(EventNotifier *notifier, uint32_t sch,
>>           .addr = sch,
>>           .len = 8,
>>       };
>> +    if (!kvm_enabled()) {
>> +        return 0;
>> +    }
>>       if (!kvm_check_extension(kvm_state, KVM_CAP_IOEVENTFD)) {
>>           return -ENOSYS;
>>       }
>>

-- 
Regards
QingFeng Hao