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authorDavid S. Miller <davem@davemloft.net>2018-08-02 20:55:32 +0300
committerDavid S. Miller <davem@davemloft.net>2018-08-02 20:55:32 +0300
commit89b1698c93a9dee043154f33d96bca9964e705f1 (patch)
treedd9dcb1965baae8edcf0b496aaa6a70609b6fc11 /kernel/stop_machine.c
parentffd7ce3cd9c294f1ff49ec02cdbd1bc7cb913db6 (diff)
parente30cb13c5a09ff5f043a6570c32e49b063bea6a1 (diff)
downloadlinux-89b1698c93a9dee043154f33d96bca9964e705f1.tar.xz
Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/net
The BTF conflicts were simple overlapping changes. The virtio_net conflict was an overlap of a fix of statistics counter, happening alongisde a move over to a bonafide statistics structure rather than counting value on the stack. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'kernel/stop_machine.c')
-rw-r--r--kernel/stop_machine.c10
1 files changed, 9 insertions, 1 deletions
diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c
index 1ff523dae6e2..e190d1ef3a23 100644
--- a/kernel/stop_machine.c
+++ b/kernel/stop_machine.c
@@ -260,6 +260,15 @@ retry:
err = 0;
__cpu_stop_queue_work(stopper1, work1, &wakeq);
__cpu_stop_queue_work(stopper2, work2, &wakeq);
+ /*
+ * The waking up of stopper threads has to happen
+ * in the same scheduling context as the queueing.
+ * Otherwise, there is a possibility of one of the
+ * above stoppers being woken up by another CPU,
+ * and preempting us. This will cause us to n ot
+ * wake up the other stopper forever.
+ */
+ preempt_disable();
unlock:
raw_spin_unlock(&stopper2->lock);
raw_spin_unlock_irq(&stopper1->lock);
@@ -271,7 +280,6 @@ unlock:
}
if (!err) {
- preempt_disable();
wake_up_q(&wakeq);
preempt_enable();
}