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Date: Wed, 23 Dec 2009 15:19:45 -0600
From: Jason Wessel <jason.wessel@...driver.com>
To: linux-kernel@...r.kernel.org
Cc: kgdb-bugreport@...ts.sourceforge.net, kdb@....sgi.com,
mingo@...e.hu, Jason Wessel <jason.wessel@...driver.com>,
David Airlie <airlied@...ux.ie>,
Jesse Barnes <jbarnes@...tuousgeek.org>
Subject: [PATCH 32/37] kms,kdb: Force unblank a console device
The kgdboc pre exception handler must atomically save the state of the
existing VC console and activate it, if it is blanked.
Before restoring the kernel to a running state, the kgdboc post
exception handler will restore the state of the VC variables that got
changed while atomic.
CC: David Airlie <airlied@...ux.ie>
CC: Jesse Barnes <jbarnes@...tuousgeek.org>
Signed-off-by: Jason Wessel <jason.wessel@...driver.com>
---
drivers/serial/kgdboc.c | 59 ++++++++++++++++++++++++++++++++++++-----
drivers/video/console/fbcon.c | 8 +++++
2 files changed, 60 insertions(+), 7 deletions(-)
diff --git a/drivers/serial/kgdboc.c b/drivers/serial/kgdboc.c
index 93b18f9..b5d7e71 100644
--- a/drivers/serial/kgdboc.c
+++ b/drivers/serial/kgdboc.c
@@ -18,6 +18,8 @@
#include <linux/tty.h>
#include <linux/console.h>
#include <linux/input.h>
+#include <linux/vt_kern.h>
+#include <linux/selection.h>
#define MAX_CONFIG_LEN 40
@@ -204,13 +206,50 @@ static int param_set_kgdboc_var(const char *kmessage, struct kernel_param *kp)
return configure_kgdboc();
}
+#ifdef CONFIG_VT
+static int dbg_orig_vc_mode;
+static int saved_fg_con;
+static int saved_last_con;
+static int saved_want_con;
+
+static void kgdboc_pre_vt_hook(void)
+{
+ struct vc_data *vc = vc_cons[fg_console].d;
+ saved_fg_con = fg_console;
+ saved_last_con = last_console;
+ saved_want_con = want_console;
+ dbg_orig_vc_mode = vc->vc_mode;
+ vc->vc_mode = KD_TEXT;
+ console_blanked = 0;
+ vc->vc_sw->con_blank(vc, 0, 1);
+ vc->vc_sw->con_set_palette(vc, color_table);
+}
+
+static void kgdboc_post_vt_hook(void)
+{
+ fg_console = saved_fg_con;
+ last_console = saved_last_con;
+ want_console = saved_want_con;
+ vc_cons[fg_console].d->vc_mode = dbg_orig_vc_mode;
+}
+#else
+#define kgdboc_pre_vt_hook()
+#define kgdboc_post_vt_hook()
+#endif /* CONFIG_VT */
+
+static int dbg_restore_graphics;
+
static void kgdboc_pre_exp_handler(void)
{
- if (kgdboc_use_kms && dbg_kms_console_core &&
- dbg_kms_console_core->activate_console)
- if (dbg_kms_console_core->activate_console(dbg_kms_console_core))
+ if (!dbg_restore_graphics && kgdboc_use_kms && dbg_kms_console_core &&
+ dbg_kms_console_core->activate_console) {
+ if (dbg_kms_console_core->activate_console(dbg_kms_console_core)) {
printk(KERN_ERR "kgdboc: kernel mode switch error\n");
-
+ } else {
+ dbg_restore_graphics = 1;
+ kgdboc_pre_vt_hook();
+ }
+ }
/* Increment the module count when the debugger is active */
if (!kgdb_connected)
try_module_get(THIS_MODULE);
@@ -222,9 +261,15 @@ static void kgdboc_post_exp_handler(void)
if (!kgdb_connected)
module_put(THIS_MODULE);
if (kgdboc_use_kms && dbg_kms_console_core &&
- dbg_kms_console_core->restore_console)
- if (dbg_kms_console_core->restore_console(dbg_kms_console_core))
- printk(KERN_ERR "kgdboc: graphics restore failed\n");
+ dbg_kms_console_core->restore_console) {
+ if (dbg_restore_graphics) {
+ if (dbg_kms_console_core->restore_console(dbg_kms_console_core))
+ printk(KERN_ERR "kgdboc: graphics restore failed\n");
+ dbg_restore_graphics = 0;
+ kgdboc_post_vt_hook();
+ }
+ }
+
#ifdef CONFIG_KDB_KEYBOARD
/* If using the kdb keyboard driver release all the keys. */
if (kgdboc_use_kbd)
diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c
index 3681c6a..138a25c 100644
--- a/drivers/video/console/fbcon.c
+++ b/drivers/video/console/fbcon.c
@@ -75,6 +75,7 @@
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/crc32.h> /* For counting font checksums */
+#include <linux/kgdb.h>
#include <asm/fb.h>
#include <asm/irq.h>
#include <asm/system.h>
@@ -2318,6 +2319,13 @@ static int fbcon_blank(struct vc_data *vc, int blank, int mode_switch)
}
}
+#ifdef CONFIG_KGDB_KDB
+ if (atomic_read(&kgdb_active) != -1) {
+ if (info->fbops->fb_blank)
+ info->fbops->fb_blank(blank, info);
+ return 0;
+ }
+#endif
if (!fbcon_is_inactive(vc, info)) {
if (ops->blank_state != blank) {
ops->blank_state = blank;
--
1.6.4.rc1
--
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