Merge tag 'kvm-s390-next-6.17-1' of https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

RCU wakeup fix for KVM s390 guest entry

1 files changed, 16 insertions, 0 deletions

diff --git a/include/linux/entry-common.h b/include/linux/entry-common.h
index f94f3fdf15fc..3bf99cbad8a3 100644
--- a/include/linux/entry-common.h
+++ b/include/linux/entry-common.h
@@ -87,6 +87,22 @@ static __always_inline void arch_enter_from_user_mode(struct pt_regs *regs) {}
 #endif
 
 /**
+ * arch_in_rcu_eqs - Architecture specific check for RCU extended quiescent
+ * states.
+ *
+ * Returns: true if the CPU is potentially in an RCU EQS, false otherwise.
+ *
+ * Architectures only need to define this if threads other than the idle thread
+ * may have an interruptible EQS. This does not need to handle idle threads. It
+ * is safe to over-estimate at the cost of redundant RCU management work.
+ *
+ * Invoked from irqentry_enter()
+ */
+#ifndef arch_in_rcu_eqs
+static __always_inline bool arch_in_rcu_eqs(void) { return false; }
+#endif
+
+/**
  * enter_from_user_mode - Establish state when coming from user mode
  *
  * Syscall/interrupt entry disables interrupts, but user mode is traced as