From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Tue, 6 Dec 2011 22:43:47 +1100
From: Paul Mackerras <paulus@samba.org>
To: Alexander Graf <agraf@suse.de>, Scott Wood <scottwood@freescale.com>
Subject: Re: "KVM: PPC: booke: Improve timer register emulation" breaks
 Book3s HV
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On Tue, Dec 06, 2011 at 03:03:00PM +1100, Paul Mackerras wrote:
> I'm not sure why yet, but commit 8a97c432 ("KVM: PPC: booke: Improve
> timer register emulation") in Alex's kvm-ppc-next branch is breaking
> Book3S HV KVM on POWER7.  Guest cpus fail to spin up, and even with
> just one cpu, the guest stalls every so often.  If I stop the guest
> and inspect the state with qemu, PC is at 0x900.  Reverting 8a97c432
> makes it work properly again.

This fixes it:

diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 534cbe1..83bcb44 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -560,7 +560,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
 
 void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
 {
-	if (waitqueue_active(&vcpu->wq)) {
+	if (waitqueue_active(vcpu->arch.wqp)) {
 		wake_up_interruptible(vcpu->arch.wqp);
 		vcpu->stat.halt_wakeup++;
 	} else if (vcpu->cpu != -1) {

Alex, do you want to roll that in with Scott's patch, or do you want me
to send a separate patch on top?

Paul.