Merge tag 's390-5.19-7' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 fix from Alexander GordeevL

 - Prevent relatively slow PRNO TRNG random number operation from being
   called from interrupt context. That could for example cause some
   network loads to timeout.

* tag 's390-5.19-7' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/archrandom: prevent CPACF trng invocations in interrupt context

Author: torvalds

arch/s390/include/asm/archrandom.h

@@ -2,7 +2,7 @@
 /*
  * Kernel interface for the s390 arch_random_* functions
  *
- * Copyright IBM Corp. 2017, 2020
+ * Copyright IBM Corp. 2017, 2022
  *
  * Author: Harald Freudenberger <freude@de.ibm.com>
  *
@@ -14,6 +14,7 @@
 #ifdef CONFIG_ARCH_RANDOM
 
 #include <linux/static_key.h>
+#include <linux/preempt.h>
 #include <linux/atomic.h>
 #include <asm/cpacf.h>
 
@@ -32,7 +33,8 @@ static inline bool __must_check arch_get_random_int(unsigned int *v)
 
 static inline bool __must_check arch_get_random_seed_long(unsigned long *v)
 {
-	if (static_branch_likely(&s390_arch_random_available)) {
+	if (static_branch_likely(&s390_arch_random_available) &&
+	    in_task()) {
 		cpacf_trng(NULL, 0, (u8 *)v, sizeof(*v));
 		atomic64_add(sizeof(*v), &s390_arch_random_counter);
 		return true;
@@ -42,7 +44,8 @@ static inline bool __must_check arch_get_random_seed_long(unsigned long *v)
 
 static inline bool __must_check arch_get_random_seed_int(unsigned int *v)
 {
-	if (static_branch_likely(&s390_arch_random_available)) {
+	if (static_branch_likely(&s390_arch_random_available) &&
+	    in_task()) {
 		cpacf_trng(NULL, 0, (u8 *)v, sizeof(*v));
 		atomic64_add(sizeof(*v), &s390_arch_random_counter);
 		return true;