summaryrefslogtreecommitdiff
path: root/kernel/power/user.c
diff options
context:
space:
mode:
authorRafael J. Wysocki <rjw@sisk.pl>2008-10-16 09:01:21 +0400
committerLinus Torvalds <torvalds@linux-foundation.org>2008-10-16 22:21:29 +0400
commit1bfcf1304ea79c46efc3724e548b13b4b442b418 (patch)
tree5adbf95b25d1d9e86fc0e5d0784550ccb9bf5be9 /kernel/power/user.c
parent574f34cee2b6574d43bf4506f771c1cec6a5d391 (diff)
downloadlinux-1bfcf1304ea79c46efc3724e548b13b4b442b418.tar.xz
pm: rework disabling of user mode helpers during suspend/hibernation
We currently use a PM notifier to disable user mode helpers before suspend and hibernation and to re-enable them during resume. However, this is not an ideal solution, because if any drivers want to upload firmware into memory before suspend, they have to use a PM notifier for this purpose and there is no guarantee that the ordering of PM notifiers will be as expected (ie. the notifier that disables user mode helpers has to be run after the driver's notifier used for uploading the firmware). For this reason, it seems better to move the disabling and enabling of user mode helpers to separate functions that will be called by the PM core as necessary. [akpm@linux-foundation.org: remove unneeded ifdefs] Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Cc: Alan Stern <stern@rowland.harvard.edu> Acked-by: Pavel Machek <pavel@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/power/user.c')
-rw-r--r--kernel/power/user.c10
1 files changed, 9 insertions, 1 deletions
diff --git a/kernel/power/user.c b/kernel/power/user.c
index a6332a313262..005b93d839ba 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;