Commits
Christian Borntraeger committed 83987ace22f
s390/kvm: Fix BUG in include/linux/kvm_host.h:745
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.
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
CC: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>