[PATCH] swsusp: fix suspend when console is in VT_AUTO+KD_GRAPHICS mode
When the console is in VT_AUTO+KD_GRAPHICS mode, switching to the
SUSPEND_CONSOLE fails, resulting in vt_waitactive() waiting indefinitely or
until the task is interrupted. This patch tests if a console switch can
occur in set_console() and returns early if a console switch is not
possible.
[akpm@linux-foundation.org: cleanup]
Signed-off-by: Andrew Johnson <ajohnson@intrinsyc.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/char/vt.c b/drivers/char/vt.c
index c3f8e38..0fefe2a 100644
--- a/drivers/char/vt.c
+++ b/drivers/char/vt.c
@@ -2185,10 +2185,28 @@
release_console_sem();
}
-void set_console(int nr)
+int set_console(int nr)
{
+ struct vc_data *vc = vc_cons[fg_console].d;
+
+ if (!vc_cons_allocated(nr) || vt_dont_switch ||
+ (vc->vt_mode.mode == VT_AUTO && vc->vc_mode == KD_GRAPHICS)) {
+
+ /*
+ * Console switch will fail in console_callback() or
+ * change_console() so there is no point scheduling
+ * the callback
+ *
+ * Existing set_console() users don't check the return
+ * value so this shouldn't break anything
+ */
+ return -EINVAL;
+ }
+
want_console = nr;
schedule_console_callback();
+
+ return 0;
}
struct tty_driver *console_driver;
diff --git a/drivers/char/vt_ioctl.c b/drivers/char/vt_ioctl.c
index 3a5d301..1fa2da8 100644
--- a/drivers/char/vt_ioctl.c
+++ b/drivers/char/vt_ioctl.c
@@ -34,7 +34,7 @@
#include <linux/kbd_diacr.h>
#include <linux/selection.h>
-static char vt_dont_switch;
+char vt_dont_switch;
extern struct tty_driver *console_driver;
#define VT_IS_IN_USE(i) (console_driver->ttys[i] && console_driver->ttys[i]->count)
diff --git a/include/linux/kbd_kern.h b/include/linux/kbd_kern.h
index 06c58c4..506ad20 100644
--- a/include/linux/kbd_kern.h
+++ b/include/linux/kbd_kern.h
@@ -75,7 +75,7 @@
extern void (*kbd_ledfunc)(unsigned int led);
-extern void set_console(int nr);
+extern int set_console(int nr);
extern void schedule_console_callback(void);
static inline void set_leds(void)
diff --git a/include/linux/vt_kern.h b/include/linux/vt_kern.h
index 37a1a41..e0db669 100644
--- a/include/linux/vt_kern.h
+++ b/include/linux/vt_kern.h
@@ -83,6 +83,7 @@
#define CON_BUF_SIZE (CONFIG_BASE_SMALL ? 256 : PAGE_SIZE)
extern char con_buf[CON_BUF_SIZE];
extern struct semaphore con_buf_sem;
+extern char vt_dont_switch;
struct vt_spawn_console {
spinlock_t lock;
diff --git a/kernel/power/console.c b/kernel/power/console.c
index 623786d..89bcf49 100644
--- a/kernel/power/console.c
+++ b/kernel/power/console.c
@@ -27,7 +27,15 @@
return 1;
}
- set_console(SUSPEND_CONSOLE);
+ if (set_console(SUSPEND_CONSOLE)) {
+ /*
+ * We're unable to switch to the SUSPEND_CONSOLE.
+ * Let the calling function know so it can decide
+ * what to do.
+ */
+ release_console_sem();
+ return 1;
+ }
release_console_sem();
if (vt_waitactive(SUSPEND_CONSOLE)) {
