On 2/17/26 3:56 PM, Christian Zigotzky wrote:
On 17/02/26 11:17 Madhavan Srinivasan wrote:
On 2/17/26 3:14 PM, Christian Zigotzky wrote:
On 17/02/26 10:03, Shrikanth Hegde wrote:
On 2/17/26 2:22 PM, Christian Zigotzky wrote:
Hi,
Thank you for your patch. I tested the latest git kernel with your
patch today. Unfortunately the system freezes while booting the VM
with KVM HV.
Cheers,
Christian
Would it be possible to share the console log or boot log of KVM to the
point it freezes?
Unfortunately there aren't any error messages.
I also tried it with:
gdb --args qemu-system-ppc64 -M ppce500 -cpu e5500 -m 1024 -kernel
uImage-7.0-preempt -drive format=raw,file=void-live-powerpc-20230317-
updated2.img,index=0,if=virtio -netdev user,id=mynet0 -device virtio-
net,netdev=mynet0 -append "rw root=/dev/vda" -device virtio-gpu-pci -
device virtio-mouse-pci -device virtio-keyboard-pci -enable-kvm -smp 4
and with gdb in the guest:
qemu-system-ppc64 -s -S -M ppce500 -cpu e5500 -m 1024 -kernel
uImage-7.0-preempt -drive format=raw,file=void-live-powerpc-20230317-
updated2.img,index=0,if=virtio -netdev user,id=mynet0 -device virtio-
net,netdev=mynet0 -append "rw root=/dev/vda" -device virtio-gpu-pci -
device virtio-mouse-pci -device virtio-keyboard-pci -enable-kvm -smp 4
The system freezed without any error messages.
Anything on host console?
can you please share the config.
I tried kvm-hv in my power8/power9 and seems to boot fine without any
issues with today's upstream
Maddy
Here are the configs.
With PREEMPT: https://github.com/chzigotzky/kernels/blob/
d50d259ca63dd2b3b9a9eaabc82e5cc69c8cc9f0/configs/e5500_defconfig
Without PREEMPT: https://github.com/chzigotzky/kernels/blob/main/
configs/e5500_defconfig
- Christian
I looked at the code. there was one more place where cond_resched was
there.
If possible give the below try.
(Note: Didn;t replicate your issue)
---
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 7667563fb9ff..bf0ca49c9915 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -4825,10 +4825,13 @@ static int kvmppc_run_vcpu(struct kvm_vcpu *vcpu)
vc->runner = vcpu;
if (n_ceded == vc->n_runnable) {
kvmppc_vcore_blocked(vc);
- } else if (need_resched()) {
+ } else if (need_resched() || spin_needbreak(&vc->lock)) {
kvmppc_vcore_preempt(vc);
/* Let something else run */
- cond_resched_lock(&vc->lock);
+ spin_unlock(&vc->lock);
+ schedule();
+ //cond_resched_lock(&vc->lock);
+ spin_lock(&vc->lock);
if (vc->vcore_state == VCORE_PREEMPT)
kvmppc_vcore_end_preempt(vc);
} else {
@@ -4901,7 +4904,7 @@ int kvmhv_run_single_vcpu(struct kvm_vcpu *vcpu,
u64 time_limit,
}
if (need_resched())
- cond_resched();
+ schedule();
kvmppc_update_vpas(vcpu);
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 9a89a6d98f97..54963c1d8b58 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -86,7 +86,7 @@ int kvmppc_prepare_to_enter(struct kvm_vcpu *vcpu)
while (true) {
if (need_resched()) {
local_irq_enable();
- cond_resched();
+ schedule();
hard_irq_disable();
continue;
}
