Merge tag 'kvm-s390-master-6.11-1' of https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

Fix invalid gisa designation value when gisa is not in use.
Panic if (un)share fails to maintain security.

Author: bonzini

arch/s390/include/asm/uv.h

@@ -441,7 +441,10 @@ static inline int share(unsigned long addr, u16 cmd)
 
 	if (!uv_call(0, (u64)&uvcb))
 		return 0;
-	return -EINVAL;
+	pr_err("%s UVC failed (rc: 0x%x, rrc: 0x%x), possible hypervisor bug.\n",
+	       uvcb.header.cmd == UVC_CMD_SET_SHARED_ACCESS ? "Share" : "Unshare",
+	       uvcb.header.rc, uvcb.header.rrc);
+	panic("System security cannot be guaranteed unless the system panics now.\n");
 }
 
 /*

arch/s390/kvm/kvm-s390.h

@@ -267,7 +267,12 @@ static inline unsigned long kvm_s390_get_gfn_end(struct kvm_memslots *slots)
 
 static inline u32 kvm_s390_get_gisa_desc(struct kvm *kvm)
 {
-	u32 gd = virt_to_phys(kvm->arch.gisa_int.origin);
+	u32 gd;
+
+	if (!kvm->arch.gisa_int.origin)
+		return 0;
+
+	gd = virt_to_phys(kvm->arch.gisa_int.origin);
 
 	if (gd && sclp.has_gisaf)
 		gd |= GISA_FORMAT1;