[PATCH 04/16] x86/reboot: Assert that IRQs are disabled when turning off virtualization

[Sean Christopherson]

Assert that IRQs are disabled when turning off virtualization in an
emergency.  KVM enables hardware via on_each_cpu(), i.e. could re-enable
hardware if a pending IPI were delivered after disabling virtualization.

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
 arch/x86/kernel/reboot.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
index 78182b2969db..40ea16ecb3b8 100644
--- a/arch/x86/kernel/reboot.c
+++ b/arch/x86/kernel/reboot.c
@@ -838,6 +838,8 @@ int crashing_cpu = -1;
  */
 void cpu_emergency_disable_virtualization(void)
 {
+	lockdep_assert_irqs_disabled();
+
 #if IS_ENABLED(CONFIG_KVM_INTEL)
 	cpu_crash_vmclear_loaded_vmcss();
 #endif
-- 
2.39.0.rc0.267.gcb52ba06e7-goog