[PATCH AUTOSEL 4.4 3/5] Input: evdev - add a schedule point in evdev_write()

From: Sasha Levin
Date: Mon Oct 22 2018 - 06:22:44 EST


From: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>

[ Upstream commit 36d2582ff235b4e01ad64a734c877a52dc762d9c ]

Large writes to evdev interface may cause rcu stalls. Let's add
cond_resched() to the loop to avoid this.

Reviewed-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxx>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/input/evdev.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
index e9ae3d500a55..0bf5ad9cc492 100644
--- a/drivers/input/evdev.c
+++ b/drivers/input/evdev.c
@@ -558,6 +558,7 @@ static ssize_t evdev_write(struct file *file, const char __user *buffer,

input_inject_event(&evdev->handle,
event.type, event.code, event.value);
+ cond_resched();
}

out:
--
2.17.1