[PATCH 3.11 088/182] KVM: PPC: Book3S HV: Fix KVM hang with CONFIG_KVM_XICS=n

From: Luis Henriques
Date: Thu Apr 24 2014 - 06:07:52 EST


3.11.10.9 -stable review patch. If anyone has any objections, please let me know.

------------------

From: Anton Blanchard <anton@xxxxxxxxx>

commit 7505258c5fcb0a1cc3c76a47b4cf9506d21d10e6 upstream.

I noticed KVM is broken when KVM in-kernel XICS emulation
(CONFIG_KVM_XICS) is disabled.

The problem was introduced in 48eaef05 (KVM: PPC: Book3S HV: use
xics_wake_cpu only when defined). It used CONFIG_KVM_XICS to wrap
xics_wake_cpu, where CONFIG_PPC_ICP_NATIVE should have been
used.

Signed-off-by: Anton Blanchard <anton@xxxxxxxxx>
Signed-off-by: Paul Mackerras <paulus@xxxxxxxxx>
Acked-by: Scott Wood <scottwood@xxxxxxxxxxxxx>
[ luis: backported to 3.11: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@xxxxxxxxxxxxx>
---
arch/powerpc/kvm/book3s_hv.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 5648808..abdbd35 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -82,7 +82,7 @@ void kvmppc_fast_vcpu_kick(struct kvm_vcpu *vcpu)

/* CPU points to the first thread of the core */
if (cpu != me && cpu >= 0 && cpu < nr_cpu_ids) {
-#ifdef CONFIG_KVM_XICS
+#ifdef CONFIG_PPC_ICP_NATIVE
int real_cpu = cpu + vcpu->arch.ptid;
if (paca[real_cpu].kvm_hstate.xics_phys)
xics_wake_cpu(real_cpu);
@@ -1093,9 +1093,7 @@ static void kvmppc_start_thread(struct kvm_vcpu *vcpu)
smp_wmb();
#if defined(CONFIG_PPC_ICP_NATIVE) && defined(CONFIG_SMP)
if (vcpu->arch.ptid) {
-#ifdef CONFIG_KVM_XICS
xics_wake_cpu(cpu);
-#endif
++vc->n_woken;
}
#endif
--
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/