KVM: x86: Use mutex guards to eliminate __kvm_x86_vendor_init()

Use the recently introduced guard(mutex) infrastructure acquire and
automatically release vendor_module_lock when the guard goes out of scope.
Drop the inner __kvm_x86_vendor_init(), its sole purpose was to simplify
releasing vendor_module_lock in error paths.

No functional change intended.

Signed-off-by: Nikolay Borisov <nik.borisov@suse.com>
Reviewed-by: Kai Huang <kai.huang@intel.com>
Link: https://lore.kernel.org/r/20231030141728.1406118-1-nik.borisov@suse.com
[sean: rewrite changelog]
Signed-off-by: Sean Christopherson <seanjc@google.com>

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 363b1c08020578b090b53d74482d9c8912629ec9..709844fcd52117b30993461a9e14fa0b9a9e3272 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9632,11 +9632,13 @@ static void kvm_x86_check_cpu_compat(void *ret)
        *(int *)ret = kvm_x86_check_processor_compatibility();
 }
 
-static int __kvm_x86_vendor_init(struct kvm_x86_init_ops *ops)
+int kvm_x86_vendor_init(struct kvm_x86_init_ops *ops)
 {
        u64 host_pat;
        int r, cpu;
 
+       guard(mutex)(&vendor_module_lock);
+
        if (kvm_x86_ops.hardware_enable) {
                pr_err("already loaded vendor module '%s'\n", kvm_x86_ops.name);
                return -EEXIST;
@@ -9766,17 +9768,6 @@ out_free_x86_emulator_cache:
        kmem_cache_destroy(x86_emulator_cache);
        return r;
 }
-
-int kvm_x86_vendor_init(struct kvm_x86_init_ops *ops)
-{
-       int r;
-
-       mutex_lock(&vendor_module_lock);
-       r = __kvm_x86_vendor_init(ops);
-       mutex_unlock(&vendor_module_lock);
-
-       return r;
-}
 EXPORT_SYMBOL_GPL(kvm_x86_vendor_init);
 
 void kvm_x86_vendor_exit(void)