diff options
| author | Jason Wessel <jason.wessel@windriver.com> | 2010-03-03 15:35:57 -0600 |
|---|---|---|
| committer | Jason Wessel <jason.wessel@windriver.com> | 2010-03-03 15:35:57 -0600 |
| commit | f037983f9f7e50cc4ef13a1c565cbfa48c311a65 (patch) | |
| tree | f18006a704431e75bc0d227e31c1b9c7f1757f2d /kernel | |
| parent | a628366fc0c1faea44aba267e8ea63ff2bc74b93 (diff) | |
kms,kdb: Force unblank a console device
The kgdboc pre exception handler must atomically save the state of the
existing VT 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 VT variables that got
changed while atomic.
CC: David Airlie <airlied@linux.ie>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/debug/Makefile | 1 | ||||
| -rw-r--r-- | kernel/debug/kms_hooks.c | 62 |
2 files changed, 63 insertions, 0 deletions
diff --git a/kernel/debug/Makefile b/kernel/debug/Makefile index c72de0039fdc..fe342c07b154 100644 --- a/kernel/debug/Makefile +++ b/kernel/debug/Makefile @@ -3,5 +3,6 @@ # obj-$(CONFIG_KGDB) += debug_core.o gdbstub.o +obj-$(CONFIG_VT) += kms_hooks.o obj-$(CONFIG_KGDB_KDB) += kdb/ diff --git a/kernel/debug/kms_hooks.c b/kernel/debug/kms_hooks.c new file mode 100644 index 000000000000..c56b7ce28989 --- /dev/null +++ b/kernel/debug/kms_hooks.c @@ -0,0 +1,62 @@ +/* + * Created by: Jason Wessel <jason.wessel@windriver.com> + * + * Copyright (c) 2009 Wind River Systems, Inc. All Rights Reserved. + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#ifdef CONFIG_VT +#include <linux/kgdb.h> +#include <linux/console.h> +#include <linux/vt_kern.h> +#include <linux/selection.h> +#include <linux/kdb.h> +#include "kdb/kdb_private.h" + +static int dbg_orig_vc_mode; +static int saved_fg_con; +static int saved_last_con; +static int saved_want_con; + +void dbg_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); +#ifdef CONFIG_KGDB_KDB + /* Set the initial LINES variable if it is not already set */ + if (vc->vc_rows < 999) { + int linecount; + char lns[4]; + const char *setargs[3] = { + "set", + "LINES", + lns, + }; + if (kdbgetintenv(setargs[0], &linecount)) { + snprintf(lns, 4, "%i", vc->vc_rows); + kdb_set(2, setargs); + } + } +#endif /* CONFIG_KGDB_KDB */ +} +EXPORT_SYMBOL_GPL(dbg_pre_vt_hook); + +void dbg_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; +} +EXPORT_SYMBOL_GPL(dbg_post_vt_hook); +#endif /* CONFIG_VT */ |