linux-kernel - [PATCH 5/5] vt,console,kdb: preserve console

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Message-Id: <1281992789-2471-6-git-send-email-jason.wessel@windriver.com>
Date:	Mon, 16 Aug 2010 16:06:29 -0500
From:	Jason Wessel <jason.wessel@...driver.com>
To:	torvalds@...ux-foundation.org
Cc:	linux-kernel@...r.kernel.org, kgdb-bugreport@...ts.sourceforge.net,
	Jason Wessel <jason.wessel@...driver.com>,
	Andrew Morton <akpm@...ux-foundation.org>
Subject: [PATCH 5/5] vt,console,kdb: preserve console_blanked while in kdb

Commit b45cfba4e9005d64d419718e7ff7f7cab44c1994 (vt,console,kdb:
implement atomic console enter/leave functions) introduced the ability
to atomically change the console mode with kernel mode setting but did
not preserve the state of the console_blanked variable.

The console_blanked variable must be restored when executing the
con_debug_leave() or further kernel mode set changes (such as using
chvt X) will fail to correctly set the state of console.

Signed-off-by: Jason Wessel <jason.wessel@...driver.com>
Reviewed-by: Jesse Barnes <jbarnes@...tuousgeek.org>
CC: Andrew Morton <akpm@...ux-foundation.org>
---
 drivers/char/vt.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/drivers/char/vt.c b/drivers/char/vt.c
index 3af1a22..50590c7 100644
--- a/drivers/char/vt.c
+++ b/drivers/char/vt.c
@@ -198,6 +198,7 @@ static int saved_fg_console;
 static int saved_last_console;
 static int saved_want_console;
 static int saved_vc_mode;
+static int saved_console_blanked;
 
 /*
  * For each existing display, we have a pointer to console currently visible
@@ -3449,6 +3450,7 @@ int con_debug_enter(struct vc_data *vc)
 	saved_last_console = last_console;
 	saved_want_console = want_console;
 	saved_vc_mode = vc->vc_mode;
+	saved_console_blanked = console_blanked;
 	vc->vc_mode = KD_TEXT;
 	console_blanked = 0;
 	if (vc->vc_sw->con_debug_enter)
@@ -3492,6 +3494,7 @@ int con_debug_leave(void)
 	fg_console = saved_fg_console;
 	last_console = saved_last_console;
 	want_console = saved_want_console;
+	console_blanked = saved_console_blanked;
 	vc_cons[fg_console].d->vc_mode = saved_vc_mode;
 
 	vc = vc_cons[fg_console].d;
-- 
1.6.3.3

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