Commit d24d2c1c authored by Jes Sorensen's avatar Jes Sorensen Committed by Avi Kivity

KVM: ia64: fix locking order entering guest

Reorder locking as down_read() may return with local interrupts enabled,
which means we could go into vti_vcpu_run() with interrupts enabled.

This caused random crashes on the Altix as the timer interrupt tried
to read a memory mapped clock source, for which the TLB had not yet been
reinstated in the exit, before ipsr was retored.
Signed-off-by: default avatarJes Sorensen <jes@sgi.com>
Acked-by: default avatarXiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
parent 99894a79
......@@ -610,20 +610,22 @@ static int __vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
int r;
again:
preempt_disable();
local_irq_disable();
if (signal_pending(current)) {
local_irq_enable();
preempt_enable();
r = -EINTR;
kvm_run->exit_reason = KVM_EXIT_INTR;
goto out;
}
/*
* down_read() may sleep and return with interrupts enabled
*/
down_read(&vcpu->kvm->slots_lock);
preempt_disable();
local_irq_disable();
vcpu->guest_mode = 1;
kvm_guest_enter();
down_read(&vcpu->kvm->slots_lock);
r = vti_vcpu_run(vcpu, kvm_run);
if (r < 0) {
local_irq_enable();
......
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