在 2017/7/3 18:20, Christian Borntraeger 写道:
On 07/03/2017 10:51 AM, QingFeng Hao wrote:
This patch is based on a similar patch from Stefan Hajnoczi -
commit c324fd0a39c (" virtio-pci: use ioeventfd even when KVM is disabled)
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 <ha...@linux.vnet.ibm.com>
---
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;
+ }
thinking more about it. wouldnt it be better to do something like this instead
diff --git a/target/s390x/cpu.h b/target/s390x/cpu.h
index 058ddad..cc47831 100644
--- a/target/s390x/cpu.h
+++ b/target/s390x/cpu.h
@@ -1240,7 +1240,11 @@ static inline int
s390_assign_subch_ioeventfd(EventNotifier *notifier,
uint32_t sch_id, int vq,
bool assign)
{
- return kvm_s390_assign_subch_ioeventfd(notifier, sch_id, vq, assign);
+ if (kvm_enabled()) {
+ return kvm_s390_assign_subch_ioeventfd(notifier, sch_id, vq, assign);
+ } else {
+ return 0;
+ }
}
Thanks. It makes sense. I'll change it.
static inline void s390_crypto_reset(void)
FWIW, it seems that we (s390) do not have a functional equivalent function as
commit
8c56c1a592b5092d91da8d8943c17777d6462a6f ("memory: emulate ioeventfd") , so we
will
not use the iothreads.
Ok, but might s390 have skipped the iothread arguments and passed the
test, so we could
still keep this test case?
if (!kvm_check_extension(kvm_state, KVM_CAP_IOEVENTFD)) {
return -ENOSYS;
}
--
Regards
QingFeng Hao