* Re: 2.6.15-mm4: sem2mutex problem in USB OHCI
2006-01-15 0:05 ` Andrew Morton
@ 2006-01-15 4:38 ` Ingo Molnar
2006-01-15 15:31 ` Rafael J. Wysocki
2006-01-16 22:51 ` Greg KH
2006-01-16 8:21 ` Ingo Molnar
1 sibling, 2 replies; 6+ messages in thread
From: Ingo Molnar @ 2006-01-15 4:38 UTC (permalink / raw)
To: Andrew Morton; +Cc: Rafael J. Wysocki, linux-kernel, greg
* Andrew Morton <akpm@osdl.org> wrote:
> > Badness in __mutex_trylock_slowpath at kernel/mutex.c:281
> >
> > Call Trace: <IRQ> <ffffffff80148d8d>{mutex_trylock+141}
> > <ffffffff880abaf0>{:ohci_hcd:ohci_hub_status_data+480}
> > <ffffffff802d25d0>{rh_timer_func+0} <ffffffff802d24c3>{usb_hcd_poll_rh_status+67}
> err, taking a mutex from softirq context.
hm. For now, the patch below undoes the struct device ->mutex
conversion.
Ingo
--
undo struct device ->mutex conversion, the USB code uses it from softirq
context.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
----
drivers/base/bus.c | 16 ++++++++--------
drivers/base/core.c | 2 +-
drivers/base/dd.c | 36 ++++++++++++++++++------------------
drivers/base/power/resume.c | 4 ++--
drivers/base/power/suspend.c | 4 ++--
drivers/usb/core/hub.c | 8 ++++----
include/linux/device.h | 2 +-
include/linux/usb.h | 6 +++---
8 files changed, 39 insertions(+), 39 deletions(-)
Index: linux-2.6.15-mm4.q/drivers/base/bus.c
===================================================================
--- linux-2.6.15-mm4.q.orig/drivers/base/bus.c
+++ linux-2.6.15-mm4.q/drivers/base/bus.c
@@ -153,10 +153,10 @@ static ssize_t driver_unbind(struct devi
dev = bus_find_device(bus, NULL, (void *)buf, driver_helper);
if (dev && dev->driver == drv) {
if (dev->parent) /* Needed for USB */
- mutex_lock(&dev->parent->mutex);
+ down(&dev->parent->sem);
device_release_driver(dev);
if (dev->parent)
- mutex_unlock(&dev->parent->mutex);
+ up(&dev->parent->sem);
err = count;
}
put_device(dev);
@@ -180,12 +180,12 @@ static ssize_t driver_bind(struct device
dev = bus_find_device(bus, NULL, (void *)buf, driver_helper);
if (dev && dev->driver == NULL) {
if (dev->parent) /* Needed for USB */
- mutex_lock(&dev->parent->mutex);
- mutex_lock(&dev->mutex);
+ down(&dev->parent->sem);
+ down(&dev->sem);
err = driver_probe_device(drv, dev);
- mutex_unlock(&dev->mutex);
+ up(&dev->sem);
if (dev->parent)
- mutex_unlock(&dev->parent->mutex);
+ up(&dev->parent->sem);
}
put_device(dev);
put_bus(bus);
@@ -512,10 +512,10 @@ static int bus_rescan_devices_helper(str
{
if (!dev->driver) {
if (dev->parent) /* Needed for USB */
- mutex_lock(&dev->parent->mutex);
+ down(&dev->parent->sem);
device_attach(dev);
if (dev->parent)
- mutex_unlock(&dev->parent->mutex);
+ up(&dev->parent->sem);
}
return 0;
}
Index: linux-2.6.15-mm4.q/drivers/base/core.c
===================================================================
--- linux-2.6.15-mm4.q.orig/drivers/base/core.c
+++ linux-2.6.15-mm4.q/drivers/base/core.c
@@ -231,7 +231,7 @@ void device_initialize(struct device *de
klist_init(&dev->klist_children, klist_children_get,
klist_children_put);
INIT_LIST_HEAD(&dev->dma_pools);
- mutex_init(&dev->mutex);
+ init_MUTEX(&dev->sem);
device_init_wakeup(dev, 0);
}
Index: linux-2.6.15-mm4.q/drivers/base/dd.c
===================================================================
--- linux-2.6.15-mm4.q.orig/drivers/base/dd.c
+++ linux-2.6.15-mm4.q/drivers/base/dd.c
@@ -36,7 +36,7 @@
* for before calling this. (It is ok to call with no other effort
* from a driver's probe() method.)
*
- * This function must be called with @dev->mutex held.
+ * This function must be called with @dev->sem held.
*/
void device_bind_driver(struct device * dev)
{
@@ -65,8 +65,8 @@ void device_bind_driver(struct device *
* This function returns 1 if a match is found, an error if one
* occurs (that is not -ENODEV or -ENXIO), and 0 otherwise.
*
- * This function must be called with @dev->mutex held. When called
- * for a USB interface, @dev->parent->mutex must be held as well.
+ * This function must be called with @dev->sem held. When called
+ * for a USB interface, @dev->parent->sem must be held as well.
*/
int driver_probe_device(struct device_driver * drv, struct device * dev)
{
@@ -131,19 +131,19 @@ static int __device_attach(struct device
* Returns 1 if the device was bound to a driver;
* 0 if no matching device was found; error code otherwise.
*
- * When called for a USB interface, @dev->parent->mutex must be held.
+ * When called for a USB interface, @dev->parent->sem must be held.
*/
int device_attach(struct device * dev)
{
int ret = 0;
- mutex_lock(&dev->mutex);
+ down(&dev->sem);
if (dev->driver) {
device_bind_driver(dev);
ret = 1;
} else
ret = bus_for_each_drv(dev->bus, NULL, dev, __device_attach);
- mutex_unlock(&dev->mutex);
+ up(&dev->sem);
return ret;
}
@@ -162,13 +162,13 @@ static int __driver_attach(struct device
*/
if (dev->parent) /* Needed for USB */
- mutex_lock(&dev->parent->mutex);
- mutex_lock(&dev->mutex);
+ down(&dev->parent->sem);
+ down(&dev->sem);
if (!dev->driver)
driver_probe_device(drv, dev);
- mutex_unlock(&dev->mutex);
+ up(&dev->sem);
if (dev->parent)
- mutex_unlock(&dev->parent->mutex);
+ up(&dev->parent->sem);
return 0;
}
@@ -193,8 +193,8 @@ void driver_attach(struct device_driver
*
* Manually detach device from driver.
*
- * __device_release_driver() must be called with @dev->mutex held.
- * When called for a USB interface, @dev->parent->mutex must be held
+ * __device_release_driver() must be called with @dev->sem held.
+ * When called for a USB interface, @dev->parent->sem must be held
* as well.
*/
@@ -225,9 +225,9 @@ void device_release_driver(struct device
* within their ->remove callback for the same device, they
* will deadlock right here.
*/
- mutex_lock(&dev->mutex);
+ down(&dev->sem);
__device_release_driver(dev);
- mutex_unlock(&dev->mutex);
+ up(&dev->sem);
}
@@ -251,13 +251,13 @@ void driver_detach(struct device_driver
spin_unlock(&drv->klist_devices.k_lock);
if (dev->parent) /* Needed for USB */
- mutex_lock(&dev->parent->mutex);
- mutex_lock(&dev->mutex);
+ down(&dev->parent->sem);
+ down(&dev->sem);
if (dev->driver == drv)
__device_release_driver(dev);
- mutex_unlock(&dev->mutex);
+ up(&dev->sem);
if (dev->parent)
- mutex_unlock(&dev->parent->mutex);
+ up(&dev->parent->sem);
put_device(dev);
}
}
Index: linux-2.6.15-mm4.q/drivers/base/power/resume.c
===================================================================
--- linux-2.6.15-mm4.q.orig/drivers/base/power/resume.c
+++ linux-2.6.15-mm4.q/drivers/base/power/resume.c
@@ -24,7 +24,7 @@ int resume_device(struct device * dev)
{
int error = 0;
- mutex_lock(&dev->mutex);
+ down(&dev->sem);
if (dev->power.pm_parent
&& dev->power.pm_parent->power.power_state.event) {
dev_err(dev, "PM: resume from %d, parent %s still %d\n",
@@ -36,7 +36,7 @@ int resume_device(struct device * dev)
dev_dbg(dev,"resuming\n");
error = dev->bus->resume(dev);
}
- mutex_unlock(&dev->mutex);
+ up(&dev->sem);
return error;
}
Index: linux-2.6.15-mm4.q/drivers/base/power/suspend.c
===================================================================
--- linux-2.6.15-mm4.q.orig/drivers/base/power/suspend.c
+++ linux-2.6.15-mm4.q/drivers/base/power/suspend.c
@@ -39,7 +39,7 @@ int suspend_device(struct device * dev,
{
int error = 0;
- mutex_lock(&dev->mutex);
+ down(&dev->sem);
if (dev->power.power_state.event) {
dev_dbg(dev, "PM: suspend %d-->%d\n",
dev->power.power_state.event, state.event);
@@ -59,7 +59,7 @@ int suspend_device(struct device * dev,
dev_dbg(dev, "suspending\n");
error = dev->bus->suspend(dev, state);
}
- mutex_unlock(&dev->mutex);
+ up(&dev->sem);
return error;
}
Index: linux-2.6.15-mm4.q/drivers/usb/core/hub.c
===================================================================
--- linux-2.6.15-mm4.q.orig/drivers/usb/core/hub.c
+++ linux-2.6.15-mm4.q/drivers/usb/core/hub.c
@@ -33,8 +33,8 @@
#include "hub.h"
/* Protect struct usb_device->state and ->children members
- * Note: Both are also protected by ->dev.mutex, except that ->state can
- * change to USB_STATE_NOTATTACHED even when the mutex isn't held. */
+ * Note: Both are also protected by ->dev.sem, except that ->state can
+ * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
static DEFINE_SPINLOCK(device_state_lock);
/* khubd's worklist and its lock */
@@ -1786,9 +1786,9 @@ static int finish_device_resume(struct u
struct device *dev =
&udev->actconfig->interface[i]->dev;
- mutex_lock(&dev->mutex);
+ down(&dev->sem);
(void) resume(dev);
- mutex_unlock(&dev->mutex);
+ up(&dev->sem);
}
status = 0;
Index: linux-2.6.15-mm4.q/include/linux/device.h
===================================================================
--- linux-2.6.15-mm4.q.orig/include/linux/device.h
+++ linux-2.6.15-mm4.q/include/linux/device.h
@@ -314,7 +314,7 @@ struct device {
char bus_id[BUS_ID_SIZE]; /* position on parent bus */
struct device_attribute uevent_attr;
- struct mutex mutex; /* semaphore to synchronize calls to
+ struct semaphore sem; /* semaphore to synchronize calls to
* its driver.
*/
Index: linux-2.6.15-mm4.q/include/linux/usb.h
===================================================================
--- linux-2.6.15-mm4.q.orig/include/linux/usb.h
+++ linux-2.6.15-mm4.q/include/linux/usb.h
@@ -379,9 +379,9 @@ extern struct usb_device *usb_get_dev(st
extern void usb_put_dev(struct usb_device *dev);
/* USB device locking */
-#define usb_lock_device(udev) mutex_lock(&(udev)->dev.mutex)
-#define usb_unlock_device(udev) mutex_unlock(&(udev)->dev.mutex)
-#define usb_trylock_device(udev) mutex_trylock(&(udev)->dev.mutex)
+#define usb_lock_device(udev) down(&(udev)->dev.sem)
+#define usb_unlock_device(udev) up(&(udev)->dev.sem)
+#define usb_trylock_device(udev) down_trylock(&(udev)->dev.sem)
extern int usb_lock_device_for_reset(struct usb_device *udev,
struct usb_interface *iface);
^ permalink raw reply [flat|nested] 6+ messages in thread