On 08/26/2009 01:07 PM, Mohammed Gamal wrote:
On Wed, Aug 26, 2009 at 12:02 PM, Avi Kivity<avi@xxxxxxxxxx> wrote:
On 08/25/2009 01:37 AM, Mohammed Gamal wrote:
Return to userspace instead of repeatedly trying to emulate
instructions that have already failed
Signed-off-by: Mohammed Gamal<m.gamal005@xxxxxxxxx>
---
arch/x86/kvm/vmx.c | 6 +++++-
1 files changed, 5 insertions(+), 1 deletions(-)
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 6b57eed..c559bb7 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -3337,6 +3337,8 @@ static void handle_invalid_guest_state(struct
kvm_vcpu *vcpu)
if (err != EMULATE_DONE) {
kvm_report_emulation_failure(vcpu, "emulation
failure");
+ vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+ vcpu->run->internal.suberror =
KVM_INTERNAL_ERROR_EMULATION;
break;
}
@@ -3607,7 +3609,9 @@ static void vmx_vcpu_run(struct kvm_vcpu *vcpu)
vmx->entry_time = ktime_get();
/* Handle invalid guest state instead of entering VMX */
- if (vmx->emulation_required&& emulate_invalid_guest_state) {
+ if (vmx->emulation_required&& emulate_invalid_guest_state
+&& !(vcpu->run->exit_reason == KVM_EXIT_INTERNAL_ERROR&&
+ vcpu->run->internal.suberror ==
KVM_INTERNAL_ERROR_EMULATION)) {
handle_invalid_guest_state(vcpu);
return;
}
Still suffers from the same problem. You don't always update
vcpu->run->exit_reason, so you can't test it. Best to return a value from
handle_invalid_guest_state() (the standard return codes for exit handlers
are 1 for return-to-guest, 0 for return-to-host, and -errno to return with
an error).
I was thinking of the same idea since I was also concerned about
vcpu->run->exit_reason not being updated. But how can we interpret the
return values of handle_invalid_guest_state() inside vmx_vcpu_run()
since it doesn't have a return value. Or would it be better to move
handle_invalid_guest_state() to the standard vmx exit handlers?
We can move the call to vmx_handle_exit(). We have a check for
emulate_invalid_guest_state there anyway. I don't think it should be a
standard exit handler since there is no exit_reason for it.
--
error compiling committee.c: too many arguments to function
--
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