KVM: s390: fix wait_queue handling

There are two waitqueues in kvm for wait handling:
vcpu->wq for virt/kvm/kvm_main.c and
vpcu->arch.local_int.wq for the s390 specific wait code.

the wait handling in kvm_s390_handle_wait was broken by using different
wait_queues for add_wait queue and remove_wait_queue.

There are two options to fix the problem:
o  move all the s390 specific code to vcpu->wq and remove
   vcpu->arch.local_int.wq
o  move all the s390 specific code to vcpu->arch.local_int.wq

This patch chooses the 2nd variant for two reasons:
o  s390 does not use kvm_vcpu_block but implements its own enabled wait
   handling.
   Having a separate wait_queue make it clear, that our wait mechanism is
   different
o  the patch is much smaller

Report-by:  Julia Lawall <julia@diku.dk>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index f04f530..4d61341 100644 (file)
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -386,7 +386,7 @@ no_timer:
        }
        __unset_cpu_idle(vcpu);
        __set_current_state(TASK_RUNNING);
-       remove_wait_queue(&vcpu->wq, &wait);
+       remove_wait_queue(&vcpu->arch.local_int.wq, &wait);
        spin_unlock_bh(&vcpu->arch.local_int.lock);
        spin_unlock(&vcpu->arch.local_int.float_int->lock);
        hrtimer_try_to_cancel(&vcpu->arch.ckc_timer);