[PATCH] uml: fix net_kern workqueue abuse
Fix up the work on stack and exit scope trouble by placing the work_struct
in the uml_net_private data.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/um/drivers/net_kern.c b/arch/um/drivers/net_kern.c
index b2e9762..afe3d42 100644
--- a/arch/um/drivers/net_kern.c
+++ b/arch/um/drivers/net_kern.c
@@ -72,9 +72,11 @@
return pkt_len;
}
-static void uml_dev_close(void* dev)
+static void uml_dev_close(struct work_struct *work)
{
- dev_close( (struct net_device *) dev);
+ struct uml_net_private *lp =
+ container_of(work, struct uml_net_private, work);
+ dev_close(lp->dev);
}
irqreturn_t uml_net_interrupt(int irq, void *dev_id)
@@ -89,7 +91,6 @@
spin_lock(&lp->lock);
while((err = uml_net_rx(dev)) > 0) ;
if(err < 0) {
- DECLARE_WORK(close_work, uml_dev_close, dev);
printk(KERN_ERR
"Device '%s' read returned %d, shutting it down\n",
dev->name, err);
@@ -97,9 +98,10 @@
* again lp->lock.
* And dev_close() can be safely called multiple times on the
* same device, since it tests for (dev->flags & IFF_UP). So
- * there's no harm in delaying the device shutdown. */
- schedule_work(&close_work);
-#error this is not permitted - close_work will go out of scope
+ * there's no harm in delaying the device shutdown.
+ * Furthermore, the workqueue will not re-enqueue an already
+ * enqueued work item. */
+ schedule_work(&lp->work);
goto out;
}
reactivate_fd(lp->fd, UM_ETH_IRQ);
@@ -365,6 +367,7 @@
/* This points to the transport private data. It's still clear, but we
* must memset it to 0 *now*. Let's help the drivers. */
memset(lp, 0, size);
+ INIT_WORK(&lp->work, uml_dev_close);
/* sysfs register */
if (!driver_registered) {
diff --git a/arch/um/include/net_kern.h b/arch/um/include/net_kern.h
index 280459f..218f8b4 100644
--- a/arch/um/include/net_kern.h
+++ b/arch/um/include/net_kern.h
@@ -11,6 +11,7 @@
#include <linux/skbuff.h>
#include <linux/socket.h>
#include <linux/list.h>
+#include <linux/workqueue.h>
struct uml_net {
struct list_head list;
@@ -26,6 +27,7 @@
struct net_device *dev;
struct timer_list tl;
struct net_device_stats stats;
+ struct work_struct work;
int fd;
unsigned char mac[ETH_ALEN];
unsigned short (*protocol)(struct sk_buff *);