| Message ID | 20240209222047.394389-3-seanjc@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: x86: kvm_has_noapic_vcpu fix/cleanup | expand |
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 59119157bd20..779a5b32a5bf 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -13878,9 +13878,6 @@ module_init(kvm_x86_init); static void __exit kvm_x86_exit(void) { - /* - * If module_init() is implemented, module_exit() must also be - * implemented to allow module unload. - */ + WARN_ON_ONCE(static_branch_unlikely(&kvm_has_noapic_vcpu)); } module_exit(kvm_x86_exit);
WARN if kvm.ko is unloaded with an elevated kvm_has_noapic_vcpu to guard against incorrect management of the key, e.g. to detect if KVM fails to decrement the key in error paths. Because kvm_has_noapic_vcpu is purely an optimization, in all likelihood KVM could completely botch handling of kvm_has_noapic_vcpu and no one would notice (which is a good argument for deleting the key entirely, but that's a problem for another day). Note, ideally the sanity check would be performance when kvm_usage_count goes to zero, but adding an arch callback just for this sanity check isn't at all worth doing. Signed-off-by: Sean Christopherson <seanjc@google.com> --- arch/x86/kvm/x86.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-)