Commit cab7a1ee authored Jul 22, 2008 by Julia Lawall Committed by Avi Kivity Jul 27, 2008

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>

parent 5fdbcb9d

arch/ia64/kvm/kvm-ia64.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -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;
		}

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