Re: [patch 1/2] KVM: x86: set debug registers after "schedulable" section

[Avi Kivity]

Marcelo Tosatti wrote:

The vcpu thread can be preempted after the guest_debug_pre() callback,
resulting in invalid debug registers on the new vcpu.

Move it inside the non-preemptable section.
  


Applied, thanks.

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error compiling committee.c: too many arguments to function

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[patch 1/2] KVM: x86: set debug registers after "schedulable" section

[Marcelo Tosatti]

The vcpu thread can be preempted after the guest_debug_pre() callback,
resulting in invalid debug registers on the new vcpu.

Move it inside the non-preemptable section.

Signed-off-by: Marcelo Tosatti <[EMAIL PROTECTED]>

Index: kvm/arch/x86/kvm/x86.c
===
--- kvm.orig/arch/x86/kvm/x86.c
+++ kvm/arch/x86/kvm/x86.c
@@ -3088,10 +3088,6 @@ static int __vcpu_run(struct kvm_vcpu *v
down_read(&vcpu->kvm->slots_lock);
vapic_enter(vcpu);
 
-preempted:
-   if (vcpu->guest_debug.enabled)
-   kvm_x86_ops->guest_debug_pre(vcpu);
-
 again:
if (vcpu->requests)
if (test_and_clear_bit(KVM_REQ_MMU_RELOAD, &vcpu->requests))
@@ -3145,6 +3141,9 @@ again:
goto out;
}
 
+   if (vcpu->guest_debug.enabled)
+   kvm_x86_ops->guest_debug_pre(vcpu);
+
vcpu->guest_mode = 1;
/*
 * Make sure that guest_mode assignment won't happen after
@@ -3219,7 +3218,7 @@ out:
if (r > 0) {
kvm_resched(vcpu);
down_read(&vcpu->kvm->slots_lock);
-   goto preempted;
+   goto again;
}
 
post_kvm_run_save(vcpu, kvm_run);

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