Hi list,
as was recently discussed, sleep_on and derivates, which have a little race
problem are used 21 times in drivers/usb
The attached patch should fix one such place in printer.
It even compiles.
20 more to go. People let's kill them all.
Regards
Oliver
--- drivers/usb/printer.c.alt Wed May 2 10:41:46 2001
+++ drivers/usb/printer.c Wed May 2 10:49:14 2001
@@ -388,6 +388,7 @@
static ssize_t usblp_read(struct file *file, char *buffer, size_t count, loff_t *ppos)
{
struct usblp *usblp = file->private_data;
+ DECLARE_WAITQUEUE(wait, current);
if (!usblp->bidir)
return -EINVAL;
@@ -396,12 +397,19 @@
if (file->f_flags & O_NONBLOCK)
return -EAGAIN;
-
+
+ current->state = TASK_INTERRUPTIBLE;
+ add_wait_queue(&usblp->wait, &wait);
while (usblp->readurb.status == -EINPROGRESS) {
- if (signal_pending(current))
+ if (signal_pending(current)) {
+ remove_wait_queue(&usblp->wait, &wait);
+ current->state = TASK_RUNNING;
return -EINTR;
- interruptible_sleep_on(&usblp->wait);
+ }
+ schedule();
}
+ remove_wait_queue(&usblp->wait, &wait);
+ current->state = TASK_RUNNING;
}
if (!usblp->dev)
@@ -668,3 +676,4 @@
MODULE_AUTHOR("Michael Gee, Pavel Machek, Vojtech Pavlik, Randy Dunlap");
MODULE_DESCRIPTION("USB Printer Device Class driver");
+
