kvm: async_pf: fix rcu_irq_enter() with irqs enabled

commit bbaf0e2b1c1b4f88abd6ef49576f0efb1734eae5 upstream.

native_safe_halt enables interrupts, and you just shouldn't
call rcu_irq_enter() with interrupts enabled.  Reorder the
call with the following local_irq_disable() to respect the
invariant.

Reported-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index 94f6434843008c38b8a091c077e0c94fc36c9a07..cb1a9b268e183cc162984d08b8269b36d0b87467 100644 (file)
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -161,8 +161,8 @@ void kvm_async_pf_task_wait(u32 token)
                         */
                        rcu_irq_exit();
                        native_safe_halt();
-                       rcu_irq_enter();
                        local_irq_disable();
+                       rcu_irq_enter();
                }
        }
        if (!n.halted)