From ae670dad61d0e714d076ece40302fe694d1bd382 Mon Sep 17 00:00:00 2001
From: Maksim Yevmenkin <emax@FreeBSD.org>
Date: Sun, 16 Nov 2008 22:39:04 +0000
Subject: [PATCH] More locking for syscons(4). This should prevent races with
 sckbdevent().

PR:		kern/127446
Submitted by:	Eygene Ryabinkin rea-fbsd at codelabs dot ru
---
 sys/dev/syscons/syscons.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/sys/dev/syscons/syscons.c b/sys/dev/syscons/syscons.c
index 37b08b6b24e..90b5afaa2dc 100644
--- a/sys/dev/syscons/syscons.c
+++ b/sys/dev/syscons/syscons.c
@@ -1572,6 +1572,7 @@ sccngetch(int flags)
     int s = spltty();	/* block sckbdevent and scrn_timer while we poll */
     int c;
 
+    mtx_lock(&Giant);
     /* assert(sc_console != NULL) */
 
     /* 
@@ -1583,11 +1584,13 @@ sccngetch(int flags)
     sccnupdate(scp);
 
     if (fkeycp < fkey.len) {
+	mtx_unlock(&Giant);
 	splx(s);
 	return fkey.str[fkeycp++];
     }
 
     if (scp->sc->kbd == NULL) {
+	mtx_unlock(&Giant);
 	splx(s);
 	return -1;
     }
@@ -1610,6 +1613,7 @@ sccngetch(int flags)
     scp->kbd_mode = cur_mode;
     kbdd_ioctl(scp->sc->kbd, KDSKBMODE, (caddr_t)&scp->kbd_mode);
     kbdd_disable(scp->sc->kbd);
+    mtx_unlock(&Giant);
     splx(s);
 
     switch (KEYFLAGS(c)) {