From 78f87ce2a17f0aa625451835ffaceb6b607b4a9a Mon Sep 17 00:00:00 2001
From: Paolo Bonzini <pbonzini@redhat.com>
Date: Wed, 26 Apr 2017 16:56:26 +0200
Subject: kvm: async_pf: fix rcu_irq_enter() with irqs enabled
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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 edbbfc8..9cf697c 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -162,8 +162,8 @@ 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)
-- 
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