kvmppc_lazy_ee_enable() was causing interrupts to be soft-enabled
(albeit hard-disabled) in kvmppc_restart_interrupt().  This led to
warnings, and possibly breakage if the interrupt state was later saved
and then restored (leading to interrupts being hard-and-soft enabled
when they should be at least soft-disabled).

Simply removing kvmppc_lazy_ee_enable() leaves interrupts only
soft-disabled when we enter the guest, but they will be hard-disabled
when we exit the guest -- without PACA_IRQ_HARD_DIS ever being set, so
the local_irq_enable() fails to hard-enable.

While we could just set PACA_IRQ_HARD_DIS after an exit to compensate,
instead hard-disable interrupts before entering the guest.  This way,
we won't have to worry about interactions if we take an interrupt
during the guest entry code.  While I don't see any obvious
interactions, it could change in the future (e.g. it would be bad if
the non-hv code were used on 64-bit or if 32-bit guest lazy interrupt
disabling, since the non-hv code changes IVPR among other things).

Signed-off-by: Scott Wood <scottw...@freescale.com>
Cc: Mihai Caraman <mihai.cara...@freescale.com>
---
 arch/powerpc/kvm/booke.c |    9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
index ecbe908..b216821 100644
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -666,14 +666,14 @@ int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct 
kvm_vcpu *vcpu)
                return -EINVAL;
        }
 
-       local_irq_disable();
+       hard_irq_disable();
+       trace_hardirqs_off();
        s = kvmppc_prepare_to_enter(vcpu);
        if (s <= 0) {
                local_irq_enable();
                ret = s;
                goto out;
        }
-       kvmppc_lazy_ee_enable();
 
        kvm_guest_enter();
 
@@ -1150,13 +1150,12 @@ int kvmppc_handle_exit(struct kvm_run *run, struct 
kvm_vcpu *vcpu,
         * aren't already exiting to userspace for some other reason.
         */
        if (!(r & RESUME_HOST)) {
-               local_irq_disable();
+               hard_irq_disable();
+               trace_hardirqs_off();
                s = kvmppc_prepare_to_enter(vcpu);
                if (s <= 0) {
                        local_irq_enable();
                        r = (s << 2) | RESUME_HOST | (r & RESUME_FLAG_NV);
-               } else {
-                       kvmppc_lazy_ee_enable();
                }
        }
 
-- 
1.7.10.4


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