[PATCH] KVM: VMX: Inform user about INTEL_TXT dependency

Jan Kiszka
2010-11-14T09:18:33Z

From: Jan Kiszka <jan.kiszka@siemens.com>

Without CONFIG_INTEL_TXT, the user must not enable this feature in the
BIOS. Otherwise, KVM will not work. Explain this dependency via a kernel
log message.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---
arch/x86/kvm/vmx.c | 7 ++++++-
1 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 9367abc..ebafd57 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -1306,8 +1306,13 @@ static __init int vmx_disabled_by_bios(void)
&& tboot_enabled())
return 1;
if (!(msr & FEATURE_CONTROL_VMXON_ENABLED_OUTSIDE_SMX)
- && !tboot_enabled())
+ && !tboot_enabled()) {
+#ifndef CONFIG_INTEL_TXT
+ printk(KERN_INFO "kvm: if TXT is enabled in the bios, "
+ "kvm depends on CONFIG_INTEL_TXT\n");
+#endif
return 1;
+ }
}

return 0;
--
1.7.1