On Fri, Dec 17 2021 at 19:45, Thomas Gleixner wrote:

On Fri, Dec 17 2021 at 07:29, Jing Liu wrote:

quoted

 
-static int __xstate_request_perm(u64 permitted, u64 requested)
+static int __xstate_request_perm(u64 permitted, u64 requested, bool guest)
 {
 	/*
 	 * This deliberately does not exclude !XSAVES as we still might

@@ -1605,6 +1605,7 @@ static int __xstate_request_perm(u64 permitted, u64 requested)
 	 */
 	bool compacted = cpu_feature_enabled(X86_FEATURE_XSAVES);
 	struct fpu *fpu = &current->group_leader->thread.fpu;
+	struct fpu_state_perm *perm;
 	unsigned int ksize, usize;
 	u64 mask;
 	int ret;

needs to be

      int ret = 0;

Alternatively return 0 at the end of the function.