path: root/kernel/freezer.c
diff options
authorTejun Heo <>2011-11-04 01:04:52 +0100
committerRafael J. Wysocki <>2011-11-04 22:28:15 +0100
commitd6cc76856d353a3a9c43bead33210b9216dce332 (patch)
tree06d072db1e4672ef595a1e8f411f7bd4b8e63866 /kernel/freezer.c
parent6f35c4abd7f0294166a5e0ab0401fe7949b33034 (diff)
PM / Freezer: Revert 27920651fe "PM / Freezer: Make fake_signal_wake_up() wake TASK_KILLABLE tasks too"
Commit 27920651fe "PM / Freezer: Make fake_signal_wake_up() wake TASK_KILLABLE tasks too" updated fake_signal_wake_up() used by freezer to wake up KILLABLE tasks. Sending unsolicited wakeups to tasks in killable sleep is dangerous as there are code paths which depend on tasks not waking up spuriously from KILLABLE sleep. For example. sys_read() or page can sleep in TASK_KILLABLE assuming that wait/down/whatever _killable can only fail if we can not return to the usermode. TASK_TRACED is another obvious example. The previous patch updated wait_event_freezekillable() such that it doesn't depend on the spurious wakeup. This patch reverts the offending commit. Note that the spurious KILLABLE wakeup had other implicit effects in KILLABLE sleeps in nfs and cifs and those will need further updates to regain freezekillable behavior. Signed-off-by: Tejun Heo <> Signed-off-by: Rafael J. Wysocki <>
Diffstat (limited to 'kernel/freezer.c')
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/freezer.c b/kernel/freezer.c
index 66a594e8ad2f..7b01de98bb6a 100644
--- a/kernel/freezer.c
+++ b/kernel/freezer.c
@@ -67,7 +67,7 @@ static void fake_signal_wake_up(struct task_struct *p)
unsigned long flags;
spin_lock_irqsave(&p->sighand->siglock, flags);
- signal_wake_up(p, 1);
+ signal_wake_up(p, 0);
spin_unlock_irqrestore(&p->sighand->siglock, flags);