diff options
| author | Jes Sorensen <jes@sgi.com> | 2009-04-09 16:38:14 +0200 |
|---|---|---|
| committer | Avi Kivity <avi@redhat.com> | 2009-04-22 13:52:09 +0300 |
| commit | d24d2c1cc4156102f9df9cd0425d58cabf955519 (patch) | |
| tree | 8d487aa14b570e7d7fcebb566ab785850d28dd4b /arch/ia64/kvm/kvm-ia64.c | |
| parent | 99894a799f09cf9e28296bb16e75bd5830fd2c4e (diff) | |
| download | lwn-d24d2c1cc4156102f9df9cd0425d58cabf955519.tar.gz lwn-d24d2c1cc4156102f9df9cd0425d58cabf955519.zip | |
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: Jes Sorensen <jes@sgi.com>
Acked-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Diffstat (limited to 'arch/ia64/kvm/kvm-ia64.c')
| -rw-r--r-- | arch/ia64/kvm/kvm-ia64.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/arch/ia64/kvm/kvm-ia64.c b/arch/ia64/kvm/kvm-ia64.c index 28af6a731bb8..d20a5db4c4dd 100644 --- a/arch/ia64/kvm/kvm-ia64.c +++ b/arch/ia64/kvm/kvm-ia64.c @@ -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(); |