diff --git a/include/linux/kmod.h b/include/linux/kmod.h
index a1a91577813c6bfb25ea89c9304f0c2128a87464..92213a9194e15753b91a21170cb641e97d82513d 100644
--- a/include/linux/kmod.h
+++ b/include/linux/kmod.h
@@ -99,4 +99,7 @@ struct file;
extern int call_usermodehelper_pipe(char *path, char *argv[], char *envp[],
struct file **filp);
+extern int usermodehelper_disable(void);
+extern void usermodehelper_enable(void);
+
#endif /* __LINUX_KMOD_H__ */
diff --git a/kernel/kmod.c b/kernel/kmod.c
index 2456d1a0befbd45b91cd7cb7a97ae6d2fb270c4c..ab7dd08472fce4c56311f29d7d3920a4e3bbd500 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -265,7 +265,7 @@ static void __call_usermodehelper(struct work_struct *work)
}
}
-#ifdef CONFIG_PM
+#ifdef CONFIG_PM_SLEEP
/*
* If set, call_usermodehelper_exec() will exit immediately returning -EBUSY
* (used for preventing user land processes from being created after the user
@@ -288,39 +288,37 @@ static DECLARE_WAIT_QUEUE_HEAD(running_helpers_waitq);
*/
#define RUNNING_HELPERS_TIMEOUT (5 * HZ)
-static int usermodehelper_pm_callback(struct notifier_block *nfb,
- unsigned long action,
- void *ignored)
+/**
+ * usermodehelper_disable - prevent new helpers from being started
+ */
+int usermodehelper_disable(void)
{
long retval;
- switch (action) {
- case PM_HIBERNATION_PREPARE:
- case PM_SUSPEND_PREPARE:
- usermodehelper_disabled = 1;
- smp_mb();
- /*
- * From now on call_usermodehelper_exec() won't start any new
- * helpers, so it is sufficient if running_helpers turns out to
- * be zero at one point (it may be increased later, but that
- * doesn't matter).
- */
- retval = wait_event_timeout(running_helpers_waitq,
+ usermodehelper_disabled = 1;
+ smp_mb();
+ /*
+ * From now on call_usermodehelper_exec() won't start any new
+ * helpers, so it is sufficient if running_helpers turns out to
+ * be zero at one point (it may be increased later, but that
+ * doesn't matter).
+ */
+ retval = wait_event_timeout(running_helpers_waitq,
atomic_read(&running_helpers) == 0,
RUNNING_HELPERS_TIMEOUT);
- if (retval) {
- return NOTIFY_OK;
- } else {
- usermodehelper_disabled = 0;
- return NOTIFY_BAD;
- }
- case PM_POST_HIBERNATION:
- case PM_POST_SUSPEND:
- usermodehelper_disabled = 0;
- return NOTIFY_OK;
- }
+ if (retval)
+ return 0;
- return NOTIFY_DONE;
+ usermodehelper_disabled = 0;
+ return -EAGAIN;
+}
+
+/**
+ * usermodehelper_enable - allow new helpers to be started again
+ */
+void usermodehelper_enable(void)
+{
+ usermodehelper_disabled = 0;
}
static void helper_lock(void)
@@ -334,18 +332,12 @@ static void helper_unlock(void)
if (atomic_dec_and_test(&running_helpers))
wake_up(&running_helpers_waitq);
}
-
-static void register_pm_notifier_callback(void)
-{
- pm_notifier(usermodehelper_pm_callback, 0);
-}
-#else /* CONFIG_PM */
+#else /* CONFIG_PM_SLEEP */
#define usermodehelper_disabled 0
static inline void helper_lock(void) {}
static inline void helper_unlock(void) {}
-static inline void register_pm_notifier_callback(void) {}
-#endif /* CONFIG_PM */
+#endif /* CONFIG_PM_SLEEP */
/**
* call_usermodehelper_setup - prepare to call a usermode helper
@@ -515,5 +507,4 @@ void __init usermodehelper_init(void)
{
khelper_wq = create_singlethread_workqueue("khelper");
BUG_ON(!khelper_wq);
- register_pm_notifier_callback();
}
diff --git a/kernel/power/disk.c b/kernel/power/disk.c
index bbd85c60f7419f5fca1cbf1d0b5d6e6aad37f625..331f9836383feaba687c89c3e4596edff76fb2fe 100644
--- a/kernel/power/disk.c
+++ b/kernel/power/disk.c
@@ -14,6 +14,7 @@
#include <linux/reboot.h>
#include <linux/string.h>
#include <linux/device.h>
+#include <linux/kmod.h>
#include <linux/delay.h>
#include <linux/fs.h>
#include <linux/mount.h>
@@ -520,6 +521,10 @@ int hibernate(void)
if (error)
goto Exit;
+ error = usermodehelper_disable();
+ if (error)
+ goto Exit;
+
/* Allocate memory management structures */
error = create_basic_memory_bitmaps();
if (error)
@@ -558,6 +563,7 @@ int hibernate(void)
thaw_processes();
Finish:
free_basic_memory_bitmaps();
+ usermodehelper_enable();
Exit:
pm_notifier_call_chain(PM_POST_HIBERNATION);
pm_restore_console();
@@ -634,6 +640,10 @@ static int software_resume(void)
if (error)
goto Finish;
+ error = usermodehelper_disable();
+ if (error)
+ goto Finish;
+
error = create_basic_memory_bitmaps();
if (error)
goto Finish;
@@ -656,6 +666,7 @@ static int software_resume(void)
thaw_processes();
Done:
free_basic_memory_bitmaps();
+ usermodehelper_enable();
Finish:
pm_notifier_call_chain(PM_POST_RESTORE);
pm_restore_console();
diff --git a/kernel/power/main.c b/kernel/power/main.c
index 540b16b68565e74fb9f51f68134f68cc3011b0a0..19122cf6d827d13d03e8a7520d0120d5adf92bbc 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -14,6 +14,7 @@
#include <linux/string.h>
#include <linux/delay.h>
#include <linux/errno.h>
+#include <linux/kmod.h>
#include <linux/init.h>
#include <linux/console.h>
#include <linux/cpu.h>
@@ -237,6 +238,10 @@ static int suspend_prepare(void)
if (error)
goto Finish;
+ error = usermodehelper_disable();
+ if (error)
+ goto Finish;
+
if (suspend_freeze_processes()) {
error = -EAGAIN;
goto Thaw;
@@ -256,6 +261,7 @@ static int suspend_prepare(void)
Thaw:
suspend_thaw_processes();
+ usermodehelper_enable();
Finish:
pm_notifier_call_chain(PM_POST_SUSPEND);
pm_restore_console();
@@ -376,6 +382,7 @@ int suspend_devices_and_enter(suspend_state_t state)
static void suspend_finish(void)
{
suspend_thaw_processes();
+ usermodehelper_enable();
pm_notifier_call_chain(PM_POST_SUSPEND);
pm_restore_console();
}
diff --git a/kernel/power/user.c b/kernel/power/user.c
index a6332a3132620b4563e3be8a0fbfb9639b1e5405..005b93d839ba1268da0c80c3106739ee388d996a 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -212,13 +212,20 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
case SNAPSHOT_FREEZE:
if (data->frozen)
break;
+
printk("Syncing filesystems ... ");
sys_sync();
printk("done.\n");
- error = freeze_processes();
+ error = usermodehelper_disable();
if (error)
+ break;
+
+ error = freeze_processes();
+ if (error) {
thaw_processes();
+ usermodehelper_enable();
+ }
if (!error)
data->frozen = 1;
break;
@@ -227,6 +234,7 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
if (!data->frozen || data->ready)
break;
thaw_processes();
+ usermodehelper_enable();
data->frozen = 0;
break;