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KVM: ia64: Fix irq disabling leak in error handling code

There is a call to local_irq_restore in the normal exit case, so it would
seem that there should be one on an error return as well.

The semantic patch that finds this problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
expression l;
expression E,E1,E2;
@@

local_irq_save(l);
... when != local_irq_restore(l)
    when != spin_unlock_irqrestore(E,l)
    when any
    when strict
(
if (...) { ... when != local_irq_restore(l)
               when != spin_unlock_irqrestore(E1,l)
+   local_irq_restore(l);
    return ...;
}
|
if (...)
+   {local_irq_restore(l);
    return ...;
+   }
|
spin_unlock_irqrestore(E2,l);
|
local_irq_restore(l);
)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Julia Lawall 17 лет назад
Родитель
Сommit
cab7a1eeeb
1 измененных файлов с 3 добавлено и 2 удалено
  1. 3 2
      arch/ia64/kvm/kvm-ia64.c

+ 3 - 2
arch/ia64/kvm/kvm-ia64.c

@@ -125,9 +125,9 @@ void kvm_arch_hardware_enable(void *garbage)
 				PAGE_KERNEL));
 	local_irq_save(saved_psr);
 	slot = ia64_itr_entry(0x3, KVM_VMM_BASE, pte, KVM_VMM_SHIFT);
+	local_irq_restore(saved_psr);
 	if (slot < 0)
 		return;
-	local_irq_restore(saved_psr);
 
 	spin_lock(&vp_lock);
 	status = ia64_pal_vp_init_env(kvm_vsa_base ?
@@ -160,9 +160,9 @@ void kvm_arch_hardware_disable(void *garbage)
 
 	local_irq_save(saved_psr);
 	slot = ia64_itr_entry(0x3, KVM_VMM_BASE, pte, KVM_VMM_SHIFT);
+	local_irq_restore(saved_psr);
 	if (slot < 0)
 		return;
-	local_irq_restore(saved_psr);
 
 	status = ia64_pal_vp_exit_env(host_iva);
 	if (status)
@@ -1253,6 +1253,7 @@ static int vti_vcpu_setup(struct kvm_vcpu *vcpu, int id)
 uninit:
 	kvm_vcpu_uninit(vcpu);
 fail:
+	local_irq_restore(psr);
 	return r;
 }