[tip:x86/apic] x86/apic: Add NMI_VECTOR wait to IPI shorthand

[tip-bot for Thomas Gleixner <tipbot@zytor.com>]

Commit-ID:  bd82dba2fa6ae91061e5d31399d61fe65028f714
Gitweb:     https://git.kernel.org/tip/bd82dba2fa6ae91061e5d31399d61fe65028f714
Author:     Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Mon, 22 Jul 2019 20:47:20 +0200
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Thu, 25 Jul 2019 16:11:59 +0200

x86/apic: Add NMI_VECTOR wait to IPI shorthand

To support NMI shorthand broadcasts add the safe wait for ICR idle for NMI
vector delivery.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190722105220.185838026@linutronix.de

---
 arch/x86/kernel/apic/ipi.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/apic/ipi.c b/arch/x86/kernel/apic/ipi.c
index 50c9dcc6f60e..7236fefde396 100644
--- a/arch/x86/kernel/apic/ipi.c
+++ b/arch/x86/kernel/apic/ipi.c
@@ -30,7 +30,10 @@ void __default_send_IPI_shortcut(unsigned int shortcut, int vector)
 	/*
 	 * Wait for idle.
 	 */
-	__xapic_wait_icr_idle();
+	if (unlikely(vector == NMI_VECTOR))
+		safe_apic_wait_icr_idle();
+	else
+		__xapic_wait_icr_idle();
 
 	/*
 	 * No need to touch the target chip field. Also the destination