From 8467576ac100e9c1c1bcd4fb98c87b7dd25a306a Mon Sep 17 00:00:00 2001
From: Matthew Dillon <dillon@apollo.backplane.com>
Date: Wed, 7 Dec 2011 20:18:07 -0800
Subject: [PATCH] kernel - Clear the quick-return flag when changing PSL_IOPL.

* Make sure we do a full syscall return when changing PSL_IOPL.
---
 sys/platform/pc64/x86_64/sysarch.c |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/sys/platform/pc64/x86_64/sysarch.c b/sys/platform/pc64/x86_64/sysarch.c
index c2a875b..cb8fd52 100644
--- a/sys/platform/pc64/x86_64/sysarch.c
+++ b/sys/platform/pc64/x86_64/sysarch.c
@@ -33,12 +33,15 @@
  */
 #include <sys/types.h>
 #include <sys/kernel.h>
+#include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/sysproto.h>
 #include <sys/memrange.h>
 #include <sys/errno.h>
 #include <sys/proc.h>
 
+#include <machine/cpu.h>
+
 int
 sys_sysarch(struct sysarch_args *uap)
 {
@@ -49,6 +52,7 @@ int
 cpu_set_iopl(void)
 {
 	curthread->td_lwp->lwp_md.md_regs->tf_rflags |= PSL_IOPL;
+	clear_quickret();
 	return(0);
 }
 
@@ -56,6 +60,7 @@ int
 cpu_clr_iopl(void)
 {
 	curthread->td_lwp->lwp_md.md_regs->tf_rflags &= ~PSL_IOPL;
+	clear_quickret();
 	return(0);
 }
 
-- 
1.7.7.2