USB: fix BUG: sleeping function called from invalid context at /home/jeremy/hg/xen/paravirt/linux/drivers/usb/core/urb.c:524, in_atomic():1, irqs_disabled():0
Clearly there's a bug in
drivers/usb/serial/usb-serial.c:usb_serial_put(). It shouldn't call
kref_put() while holding a spinlock.
Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index 5e1cf78..9bf01a5 100644
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -60,19 +60,19 @@
static int debug;
static struct usb_serial *serial_table[SERIAL_TTY_MINORS]; /* initially all NULL */
-static spinlock_t table_lock;
+static DEFINE_MUTEX(table_lock);
static LIST_HEAD(usb_serial_driver_list);
struct usb_serial *usb_serial_get_by_index(unsigned index)
{
struct usb_serial *serial;
- spin_lock(&table_lock);
+ mutex_lock(&table_lock);
serial = serial_table[index];
if (serial)
kref_get(&serial->kref);
- spin_unlock(&table_lock);
+ mutex_unlock(&table_lock);
return serial;
}
@@ -84,7 +84,7 @@
dbg("%s %d", __FUNCTION__, num_ports);
*minor = 0;
- spin_lock(&table_lock);
+ mutex_lock(&table_lock);
for (i = 0; i < SERIAL_TTY_MINORS; ++i) {
if (serial_table[i])
continue;
@@ -106,10 +106,10 @@
serial_table[i] = serial;
serial->port[j++]->number = i;
}
- spin_unlock(&table_lock);
+ mutex_unlock(&table_lock);
return serial;
}
- spin_unlock(&table_lock);
+ mutex_unlock(&table_lock);
return NULL;
}
@@ -172,9 +172,9 @@
void usb_serial_put(struct usb_serial *serial)
{
- spin_lock(&table_lock);
+ mutex_lock(&table_lock);
kref_put(&serial->kref, destroy_serial);
- spin_unlock(&table_lock);
+ mutex_unlock(&table_lock);
}
/*****************************************************************************
@@ -1129,7 +1129,6 @@
return -ENOMEM;
/* Initialize our global data */
- spin_lock_init(&table_lock);
for (i = 0; i < SERIAL_TTY_MINORS; ++i) {
serial_table[i] = NULL;
}