From 8497d6a21c4b17052e868bd53a74c82b557a6c46 Mon Sep 17 00:00:00 2001 From: Sebastian Ott Date: Tue, 12 Apr 2011 19:05:37 +0200 Subject: driver-core: fix race between device_register and driver_register When a device is registered to a bus it will be a) added to the list of devices of the bus and b) bind to a driver (if one matches). As a result of a driver being registered at this bus between a) and b) this device could already be bound to a driver. This leads to a warning and incorrect refcounting. To fix this add a check to device_attach to identify an already bound device. Signed-off-by: Sebastian Ott Signed-off-by: Greg Kroah-Hartman --- drivers/base/dd.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'drivers/base/dd.c') diff --git a/drivers/base/dd.c b/drivers/base/dd.c index da57ee9d63fe..7e9219b02796 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -245,6 +245,10 @@ int device_attach(struct device *dev) device_lock(dev); if (dev->driver) { + if (klist_node_attached(&dev->p->knode_driver)) { + ret = 1; + goto out_unlock; + } ret = device_bind_driver(dev); if (ret == 0) ret = 1; @@ -257,6 +261,7 @@ int device_attach(struct device *dev) ret = bus_for_each_drv(dev->bus, NULL, dev, __device_attach); pm_runtime_put_sync(dev); } +out_unlock: device_unlock(dev); return ret; } -- cgit v1.2.3 From c8705082404823a5bb3e02a32ba0764399b9e6f2 Mon Sep 17 00:00:00 2001 From: Uwe Kleine-König Date: Wed, 20 Apr 2011 09:44:46 +0200 Subject: driver core: let dev_set_drvdata return int instead of void as it can fail MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Before commit b402843 (Driver core: move dev_get/set_drvdata to drivers/base/dd.c) calling dev_set_drvdata with dev=NULL was an unchecked error. After some discussion about what to return in this case removing the check (and so producing a null pointer exception) seems fine. Signed-off-by: Uwe Kleine-König Signed-off-by: Greg Kroah-Hartman --- drivers/base/dd.c | 7 +++---- include/linux/device.h | 2 +- 2 files changed, 4 insertions(+), 5 deletions(-) (limited to 'drivers/base/dd.c') diff --git a/drivers/base/dd.c b/drivers/base/dd.c index 7e9219b02796..e3a3eff1dacc 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -413,17 +413,16 @@ void *dev_get_drvdata(const struct device *dev) } EXPORT_SYMBOL(dev_get_drvdata); -void dev_set_drvdata(struct device *dev, void *data) +int dev_set_drvdata(struct device *dev, void *data) { int error; - if (!dev) - return; if (!dev->p) { error = device_private_init(dev); if (error) - return; + return error; } dev->p->driver_data = data; + return 0; } EXPORT_SYMBOL(dev_set_drvdata); diff --git a/include/linux/device.h b/include/linux/device.h index 350ceda4de97..2215d013ca96 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -557,7 +557,7 @@ extern int device_move(struct device *dev, struct device *new_parent, extern const char *device_get_devnode(struct device *dev, mode_t *mode, const char **tmp); extern void *dev_get_drvdata(const struct device *dev); -extern void dev_set_drvdata(struct device *dev, void *data); +extern int dev_set_drvdata(struct device *dev, void *data); /* * Root device objects for grouping under /sys/devices -- cgit v1.2.3