mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

KVM: VMX: Enhance invalid guest state emulation 

- Change returned handle_invalid_guest_state() to return relevant exit codes
- Move triggering the emulation from vmx_vcpu_run() to vmx_handle_exit()
- Return to userspace instead of repeatedly trying to emulate instructions that have already failed

Signed-off-by: Mohammed Gamal <m.gamal005@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
This commit is contained in:
Mohammed Gamal 2009-09-01 12:48:18 +02:00 committed by Avi Kivity
parent abcf14b560
commit 80ced186d1
1 changed files with 20 additions and 24 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

44
arch/x86/kvm/vmx.c
View File

@ -107,7 +107,6 @@ struct vcpu_vmx {
} rmode;
int vpid;
bool emulation_required;
enum emulation_result invalid_state_emulation_result;
/* Support for vnmi-less CPUs */
int soft_vnmi_blocked;
@ -3322,35 +3321,37 @@ static int handle_nmi_window(struct kvm_vcpu *vcpu)
return 1;
}
static void handle_invalid_guest_state(struct kvm_vcpu *vcpu)
static int handle_invalid_guest_state(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
enum emulation_result err = EMULATE_DONE;
local_irq_enable();
preempt_enable();
int ret = 1;
while (!guest_state_valid(vcpu)) {
err = emulate_instruction(vcpu, 0, 0, 0);
if (err == EMULATE_DO_MMIO)
break;
if (err == EMULATE_DO_MMIO) {
ret = 0;
goto out;
}
if (err != EMULATE_DONE) {
kvm_report_emulation_failure(vcpu, "emulation failure");
break;
vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION;
ret = 0;
goto out;
}
if (signal_pending(current))
break;
goto out;
if (need_resched())
schedule();
}
preempt_disable();
local_irq_disable();
vmx->invalid_state_emulation_result = err;
vmx->emulation_required = 0;
out:
return ret;
}
/*
@ -3406,13 +3407,9 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu)
trace_kvm_exit(exit_reason, kvm_rip_read(vcpu));
/* If we need to emulate an MMIO from handle_invalid_guest_state
* we just return 0 */
if (vmx->emulation_required && emulate_invalid_guest_state) {
if (guest_state_valid(vcpu))
vmx->emulation_required = 0;
return vmx->invalid_state_emulation_result != EMULATE_DO_MMIO;
}
/* If guest state is invalid, start emulating */
if (vmx->emulation_required && emulate_invalid_guest_state)
return handle_invalid_guest_state(vcpu);
/* Access CR3 don't cause VMExit in paging mode, so we need
* to sync with guest real CR3. */
@ -3607,11 +3604,10 @@ static void vmx_vcpu_run(struct kvm_vcpu *vcpu)
if (unlikely(!cpu_has_virtual_nmis() && vmx->soft_vnmi_blocked))
vmx->entry_time = ktime_get();
/* Handle invalid guest state instead of entering VMX */
if (vmx->emulation_required && emulate_invalid_guest_state) {
handle_invalid_guest_state(vcpu);
/* Don't enter VMX if guest state is invalid, let the exit handler
start emulation until we arrive back to a valid state */
if (vmx->emulation_required && emulate_invalid_guest_state)
return;
}
if (test_bit(VCPU_REGS_RSP, (unsigned long *)&vcpu->arch.regs_dirty))
vmcs_writel(GUEST_RSP, vcpu->arch.regs[VCPU_REGS_RSP]);