2013/1/8 Christian Borntraeger <borntraeger@xxxxxxxxxx>: > commit b080935c8638e08134629d0a9ebdf35669bec14d > kvm: Directly account vtime to system on guest switch > > also removed the irq_disable/enable around kvm guest switch, which > is correct in itself. Unfortunately, there is a BUG ON that (correctly) > checks for preemptible to cover the call to rcu later on. > (Introduced with commit 8fa2206821953a50a3a02ea33fcfb3ced2fd9997 > KVM: make guest mode entry to be rcu quiescent state) > > This check might trigger depending on the kernel config. > Lets make sure that no preemption happens during kvm_guest_enter. > We can enable preemption again after the call to > rcu_virt_note_context_switch returns. > > Please note that we continue to run s390 guests with interrupts > enabled. > > CC: Frederic Weisbecker <fweisbec@xxxxxxxxx> > CC: Gleb Natapov <gleb@xxxxxxxxxx> > Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx> > --- > arch/s390/kvm/kvm-s390.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c > index c9011bf..f090e81 100644 > --- a/arch/s390/kvm/kvm-s390.c > +++ b/arch/s390/kvm/kvm-s390.c > @@ -613,7 +613,9 @@ static int __vcpu_run(struct kvm_vcpu *vcpu) > kvm_s390_deliver_pending_interrupts(vcpu); > > vcpu->arch.sie_block->icptcode = 0; > + preempt_disable(); > kvm_guest_enter(); > + preempt_enable(); Sorry for the issue. The fix looks good to me, thanks! Acked-by: Frederic Weisbecker <fweisbec@xxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
