svn commit: r320097 - stable/11/sys/x86/x86

[Glen Barber]

Author: gjb
Date: Mon Jun 19 13:26:38 2017
New Revision: 320097
URL: https://svnweb.freebsd.org/changeset/base/320097

Log:
  MFC r319942 (jhb):
  
   Don't try to assign interrupts to a CPU on single-CPU systems.
  
   All interrupts are routed to the sole CPU in that case implicitly.
   This is a regression in EARLY_AP_STARTUP.  Previously the 'assign_cpu'
   variable was only set when a multi-CPU system finished booting, so
   its value both meant that interrupts could be assigned and that
   there was more than one CPU.
  
  PR:		219882
  Approved by:	re (kib)
  Sponsored by:	The FreeBSD Foundation

Modified:
  stable/11/sys/x86/x86/intr_machdep.c
Directory Properties:
  stable/11/   (props changed)

Modified: stable/11/sys/x86/x86/intr_machdep.c
==============================================================================
--- stable/11/sys/x86/x86/intr_machdep.c	Mon Jun 19 13:25:47 2017	(r320096)
+++ stable/11/sys/x86/x86/intr_machdep.c	Mon Jun 19 13:26:38 2017	(r320097)
@@ -315,7 +315,9 @@ intr_assign_cpu(void *arg, int cpu)
 
 #ifdef EARLY_AP_STARTUP
 	MPASS(mp_ncpus == 1 || smp_started);
-	if (cpu != NOCPU) {
+
+	/* Nothing to do if there is only a single CPU. */
+	if (mp_ncpus > 1 && cpu != NOCPU) {
 #else
 	/*
 	 * Don't do anything during early boot.  We will pick up the
@@ -503,6 +505,8 @@ intr_next_cpu(void)
 
 #ifdef EARLY_AP_STARTUP
 	MPASS(mp_ncpus == 1 || smp_started);
+	if (mp_ncpus == 1)
+		return (PCPU_GET(apic_id));
 #else
 	/* Leave all interrupts on the BSP during boot. */
 	if (!assign_cpu)