Config option allows userspace to handle console during suspend/resume
instead of the kernel.
Signed-off-by: Ben Collins <ben.collins@canonical.com>
---
kernel/power/Kconfig | 15 +++++++++++++++
kernel/power/console.c | 4 ++++
2 files changed, 19 insertions(+), 0 deletions(-)
diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig
index b45da40..6855299 100644
--- a/kernel/power/Kconfig
+++ b/kernel/power/Kconfig
@@ -105,6 +105,21 @@ config SUSPEND_FREEZER
Turning OFF this setting is NOT recommended! If in doubt, say Y.
+config PM_DISABLE_CONSOLE
+ bool "Disable Power Management messing with the active console"
+ depends on PM
+ default n
+ ---help---
+ By default, PM will take over the active console (generally, this means
+ switching to the console when suspending from X). This can at times cause
+ problems, especially if userspace suspend scripts try to do things with
+ the console before or after suspending (e.g. calling vbestate).
+
+ To work around this, enable this option so that PM will not handle the
+ console.
+
+ If unsure, say N.
+
config HIBERNATION
bool "Hibernation (aka 'suspend to disk')"
depends on PM && SWAP && ARCH_HIBERNATION_POSSIBLE
diff --git a/kernel/power/console.c b/kernel/power/console.c
index b8628be..8b9706f 100644
--- a/kernel/power/console.c
+++ b/kernel/power/console.c
@@ -33,6 +33,7 @@ EXPORT_SYMBOL(pm_set_vt_switch);
int pm_prepare_console(void)
{
+#ifndef CONFIG_PM_DISABLE_CONSOLE
acquire_console_sem();
if (disable_vt_switch) {
@@ -66,11 +67,13 @@ int pm_prepare_console(void)
}
orig_kmsg = kmsg_redirect;
kmsg_redirect = SUSPEND_CONSOLE;
+#endif
return 0;
}
void pm_restore_console(void)
{
+#ifndef CONFIG_PM_DISABLE_CONSOLE
acquire_console_sem();
if (disable_vt_switch) {
release_console_sem();
@@ -79,5 +82,6 @@ void pm_restore_console(void)
set_console(orig_fgconsole);
release_console_sem();
kmsg_redirect = orig_kmsg;
+#endif
}
#endif
--
1.5.4.3
--
