KVM: PPC: Book3S HV: Endian fix for accessing VPA yield count

The VPA (virtual processor area) is defined by PAPR and is therefore
big-endian, so we need a be32_to_cpu when reading it in
kvmppc_get_yield_count().  Without this, H_CONFER always fails on a
little-endian host, causing SMP guests to waste time spinning on
spinlocks.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index b273193..de74756 100644 (file)
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -636,7 +636,7 @@ static int kvmppc_get_yield_count(struct kvm_vcpu *vcpu)
        spin_lock(&vcpu->arch.vpa_update_lock);
        lppaca = (struct lppaca *)vcpu->arch.vpa.pinned_addr;
        if (lppaca)
-               yield_count = lppaca->yield_count;
+               yield_count = be32_to_cpu(lppaca->yield_count);
        spin_unlock(&vcpu->arch.vpa_update_lock);
        return yield_count;
 }