From bdd4034df8b37841eeaf7b05f86e732ab8e0b08a Mon Sep 17 00:00:00 2001 From: Rabin Vincent Date: Mon, 23 Apr 2012 09:16:36 +0200 Subject: driver core: always handle dpm_order If !dev->class, device_move() does not respect the dpm_order. Fix it to do so. Acked-by: Rafael J. Wysocki Signed-off-by: Rabin Vincent Reviewed-by: Srinidhi Kasagar [Fixed a small dangling label compile warning] Signed-off-by: Linus Walleij Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 36 ++++++++++++++++++------------------ 1 file changed, 18 insertions(+), 18 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/core.c b/drivers/base/core.c index 346be8b..846d12b 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -1754,25 +1754,25 @@ int device_move(struct device *dev, struct device *new_parent, set_dev_node(dev, dev_to_node(new_parent)); } - if (!dev->class) - goto out_put; - error = device_move_class_links(dev, old_parent, new_parent); - if (error) { - /* We ignore errors on cleanup since we're hosed anyway... */ - device_move_class_links(dev, new_parent, old_parent); - if (!kobject_move(&dev->kobj, &old_parent->kobj)) { - if (new_parent) - klist_remove(&dev->p->knode_parent); - dev->parent = old_parent; - if (old_parent) { - klist_add_tail(&dev->p->knode_parent, - &old_parent->p->klist_children); - set_dev_node(dev, dev_to_node(old_parent)); + if (dev->class) { + error = device_move_class_links(dev, old_parent, new_parent); + if (error) { + /* We ignore errors on cleanup since we're hosed anyway... */ + device_move_class_links(dev, new_parent, old_parent); + if (!kobject_move(&dev->kobj, &old_parent->kobj)) { + if (new_parent) + klist_remove(&dev->p->knode_parent); + dev->parent = old_parent; + if (old_parent) { + klist_add_tail(&dev->p->knode_parent, + &old_parent->p->klist_children); + set_dev_node(dev, dev_to_node(old_parent)); + } } + cleanup_glue_dir(dev, new_parent_kobj); + put_device(new_parent); + goto out; } - cleanup_glue_dir(dev, new_parent_kobj); - put_device(new_parent); - goto out; } switch (dpm_order) { case DPM_ORDER_NONE: @@ -1787,7 +1787,7 @@ int device_move(struct device *dev, struct device *new_parent, device_pm_move_last(dev); break; } -out_put: + put_device(old_parent); out: device_pm_unlock(); -- cgit v1.1 From 0998d0631001288a5974afc0b2a5f568bcdecb4d Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Wed, 23 May 2012 00:09:34 +0200 Subject: device-core: Ensure drvdata = NULL when no driver is bound 1) drvdata is for a driver to store a pointer to driver specific data 2) If no driver is bound, there is no driver specific data associated with the device 3) Thus logically drvdata should be NULL if no driver is bound. But many drivers don't clear drvdata on device_release, or set drvdata early on in probe and leave it set on probe error. Both of which results in a dangling pointer in drvdata. This patch enforce for drvdata to be NULL after device_release or on probe failure. Signed-off-by: Hans de Goede Signed-off-by: Greg Kroah-Hartman --- drivers/base/dd.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/base') diff --git a/drivers/base/dd.c b/drivers/base/dd.c index 1b1cbb5..9a1e970 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -283,6 +283,7 @@ probe_failed: devres_release_all(dev); driver_sysfs_remove(dev); dev->driver = NULL; + dev_set_drvdata(dev, NULL); if (ret == -EPROBE_DEFER) { /* Driver requested deferred probing */ @@ -487,6 +488,7 @@ static void __device_release_driver(struct device *dev) drv->remove(dev); devres_release_all(dev); dev->driver = NULL; + dev_set_drvdata(dev, NULL); klist_remove(&dev->p->knode_driver); if (dev->bus) blocking_notifier_call_chain(&dev->bus->p->bus_notifier, -- cgit v1.1 From 6e7b4a59b3d7bb2dcd11c019354bf0c91037dadd Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Sat, 9 Jun 2012 15:02:59 -0700 Subject: driver core: fix some kernel-doc warnings in dma*.c Fix kernel-doc warnings in drivers/base/dma*.c: Warning(drivers/base/dma-buf.c:498): No description found for parameter 'vaddr' Warning(drivers/base/dma-coherent.c:199): No description found for parameter 'ret' Signed-off-by: Randy Dunlap Signed-off-by: Greg Kroah-Hartman --- drivers/base/dma-buf.c | 1 + drivers/base/dma-coherent.c | 1 + 2 files changed, 2 insertions(+) (limited to 'drivers/base') diff --git a/drivers/base/dma-buf.c b/drivers/base/dma-buf.c index 24e88fe..c30f3e1 100644 --- a/drivers/base/dma-buf.c +++ b/drivers/base/dma-buf.c @@ -493,6 +493,7 @@ EXPORT_SYMBOL_GPL(dma_buf_vmap); /** * dma_buf_vunmap - Unmap a vmap obtained by dma_buf_vmap. * @dmabuf: [in] buffer to vunmap + * @vaddr: [in] vmap to vunmap */ void dma_buf_vunmap(struct dma_buf *dmabuf, void *vaddr) { diff --git a/drivers/base/dma-coherent.c b/drivers/base/dma-coherent.c index 1b85949..560a717 100644 --- a/drivers/base/dma-coherent.c +++ b/drivers/base/dma-coherent.c @@ -186,6 +186,7 @@ EXPORT_SYMBOL(dma_release_from_coherent); * @vma: vm_area for the userspace memory * @vaddr: cpu address returned by dma_alloc_from_coherent * @size: size of the memory buffer allocated by dma_alloc_from_coherent + * @ret: result from remap_pfn_range() * * This checks whether the memory was allocated from the per-device * coherent memory pool and if so, maps that memory to the provided vma. -- cgit v1.1 From d1c6c030fcec6f860d9bb6c632a3ebe62e28440b Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Fri, 22 Jun 2012 18:01:40 +0800 Subject: driver core: fix shutdown races with probe/remove(v3) Firstly, .shutdown callback may touch a uninitialized hardware if dev->driver is set and .probe is not completed. Secondly, device_shutdown() may dereference a null pointer to cause oops when dev->driver is cleared after it has been checked in device_shutdown(). So just hold device lock and its parent lock(if it has) to fix the races. Cc: Alan Stern Signed-off-by: Ming Lei Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'drivers/base') diff --git a/drivers/base/core.c b/drivers/base/core.c index 846d12b..65849a9 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -1812,6 +1812,13 @@ void device_shutdown(void) while (!list_empty(&devices_kset->list)) { dev = list_entry(devices_kset->list.prev, struct device, kobj.entry); + + /* + * hold reference count of device's parent to + * prevent it from being freed because parent's + * lock is to be held + */ + get_device(dev->parent); get_device(dev); /* * Make sure the device is off the kset list, in the @@ -1820,6 +1827,11 @@ void device_shutdown(void) list_del_init(&dev->kobj.entry); spin_unlock(&devices_kset->list_lock); + /* hold lock to avoid race with probe/release */ + if (dev->parent) + device_lock(dev->parent); + device_lock(dev); + /* Don't allow any more runtime suspends */ pm_runtime_get_noresume(dev); pm_runtime_barrier(dev); @@ -1831,7 +1843,13 @@ void device_shutdown(void) dev_dbg(dev, "shutdown\n"); dev->driver->shutdown(dev); } + + device_unlock(dev); + if (dev->parent) + device_unlock(dev->parent); + put_device(dev); + put_device(dev->parent); spin_lock(&devices_kset->list_lock); } -- cgit v1.1 From 5a7689fd5b4f2094e7a32beae67f290f8619b042 Mon Sep 17 00:00:00 2001 From: Sebastian Ott Date: Mon, 2 Jul 2012 19:08:15 +0200 Subject: driver core: move uevent call to driver_register Device driver attribute groups are created after userspace is notified via an add event. Fix this by moving the kobject_uevent call to driver_register after the attribute groups are added. Signed-off-by: Sebastian Ott Signed-off-by: Greg Kroah-Hartman --- drivers/base/bus.c | 1 - drivers/base/driver.c | 3 +++ 2 files changed, 3 insertions(+), 1 deletion(-) (limited to 'drivers/base') diff --git a/drivers/base/bus.c b/drivers/base/bus.c index 2bcef65..181ed26 100644 --- a/drivers/base/bus.c +++ b/drivers/base/bus.c @@ -743,7 +743,6 @@ int bus_add_driver(struct device_driver *drv) } } - kobject_uevent(&priv->kobj, KOBJ_ADD); return 0; out_unregister: diff --git a/drivers/base/driver.c b/drivers/base/driver.c index 207c27d..1b500d6 100644 --- a/drivers/base/driver.c +++ b/drivers/base/driver.c @@ -187,6 +187,9 @@ int driver_register(struct device_driver *drv) ret = driver_add_groups(drv, drv->groups); if (ret) bus_remove_driver(drv); + + kobject_uevent(&drv->p->kobj, KOBJ_ADD); + return ret; } EXPORT_SYMBOL_GPL(driver_register); -- cgit v1.1 From 8153584e3fdf78753bf653d5f583b6ecb86e5e70 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Thu, 5 Jul 2012 14:04:44 +0100 Subject: driver core: Move deferred devices to the end of dpm_list before probing When deferred probe was originally added the idea was that devices which defer their probes would move themselves to the end of dpm_list in order to try to keep the assumptions that we're making about the list being in roughly the order things should be suspended correct. However this hasn't been what's been happening and doing it requires a lot of duplicated code to do the moves. Instead take a simple, brute force solution and have the deferred probe code push devices to the end of dpm_list before it retries the probe. This does mean we lock the dpm_list a bit more often but it's very simple and the code shouldn't be a fast path. We do the move with the deferred mutex dropped since doing things with fewer locks held simultaneously seems like a good idea. This approach was most recently suggested by Grant Likely. Signed-off-by: Mark Brown Acked-by: Rafael J. Wysocki Cc: Grant Likely , Signed-off-by: Greg Kroah-Hartman --- drivers/base/dd.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'drivers/base') diff --git a/drivers/base/dd.c b/drivers/base/dd.c index 6cd2c6c..9b0aca4 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -85,8 +85,20 @@ static void deferred_probe_work_func(struct work_struct *work) * manipulate the deferred list */ mutex_unlock(&deferred_probe_mutex); + + /* + * Force the device to the end of the dpm_list since + * the PM code assumes that the order we add things to + * the list is a good order for suspend but deferred + * probe makes that very unsafe. + */ + device_pm_lock(); + device_pm_move_last(dev); + device_pm_unlock(); + dev_dbg(dev, "Retrying from deferred list\n"); bus_probe_device(dev); + mutex_lock(&deferred_probe_mutex); put_device(dev); -- cgit v1.1 From b0d1f807f340e91b27aa721f6474956af11571da Mon Sep 17 00:00:00 2001 From: Lars-Peter Clausen Date: Tue, 3 Jul 2012 18:49:36 +0200 Subject: driver-core: Use kobj_to_dev instead of re-implementing it Signed-off-by: Lars-Peter Clausen Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 17 ++++++++--------- drivers/base/firmware_class.c | 6 ++---- 2 files changed, 10 insertions(+), 13 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/core.c b/drivers/base/core.c index 65849a9..f338037 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -85,14 +85,13 @@ const char *dev_driver_string(const struct device *dev) } EXPORT_SYMBOL(dev_driver_string); -#define to_dev(obj) container_of(obj, struct device, kobj) #define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr) static ssize_t dev_attr_show(struct kobject *kobj, struct attribute *attr, char *buf) { struct device_attribute *dev_attr = to_dev_attr(attr); - struct device *dev = to_dev(kobj); + struct device *dev = kobj_to_dev(kobj); ssize_t ret = -EIO; if (dev_attr->show) @@ -108,7 +107,7 @@ static ssize_t dev_attr_store(struct kobject *kobj, struct attribute *attr, const char *buf, size_t count) { struct device_attribute *dev_attr = to_dev_attr(attr); - struct device *dev = to_dev(kobj); + struct device *dev = kobj_to_dev(kobj); ssize_t ret = -EIO; if (dev_attr->store) @@ -182,7 +181,7 @@ EXPORT_SYMBOL_GPL(device_show_int); */ static void device_release(struct kobject *kobj) { - struct device *dev = to_dev(kobj); + struct device *dev = kobj_to_dev(kobj); struct device_private *p = dev->p; if (dev->release) @@ -200,7 +199,7 @@ static void device_release(struct kobject *kobj) static const void *device_namespace(struct kobject *kobj) { - struct device *dev = to_dev(kobj); + struct device *dev = kobj_to_dev(kobj); const void *ns = NULL; if (dev->class && dev->class->ns_type) @@ -221,7 +220,7 @@ static int dev_uevent_filter(struct kset *kset, struct kobject *kobj) struct kobj_type *ktype = get_ktype(kobj); if (ktype == &device_ktype) { - struct device *dev = to_dev(kobj); + struct device *dev = kobj_to_dev(kobj); if (dev->bus) return 1; if (dev->class) @@ -232,7 +231,7 @@ static int dev_uevent_filter(struct kset *kset, struct kobject *kobj) static const char *dev_uevent_name(struct kset *kset, struct kobject *kobj) { - struct device *dev = to_dev(kobj); + struct device *dev = kobj_to_dev(kobj); if (dev->bus) return dev->bus->name; @@ -244,7 +243,7 @@ static const char *dev_uevent_name(struct kset *kset, struct kobject *kobj) static int dev_uevent(struct kset *kset, struct kobject *kobj, struct kobj_uevent_env *env) { - struct device *dev = to_dev(kobj); + struct device *dev = kobj_to_dev(kobj); int retval = 0; /* add device node properties if present */ @@ -1132,7 +1131,7 @@ int device_register(struct device *dev) */ struct device *get_device(struct device *dev) { - return dev ? to_dev(kobject_get(&dev->kobj)) : NULL; + return dev ? kobj_to_dev(kobject_get(&dev->kobj)) : NULL; } /** diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c index 5401814..803cfc1 100644 --- a/drivers/base/firmware_class.c +++ b/drivers/base/firmware_class.c @@ -22,8 +22,6 @@ #include #include -#define to_dev(obj) container_of(obj, struct device, kobj) - MODULE_AUTHOR("Manuel Estrada Sainz"); MODULE_DESCRIPTION("Multi purpose firmware loading support"); MODULE_LICENSE("GPL"); @@ -290,7 +288,7 @@ static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj, struct bin_attribute *bin_attr, char *buffer, loff_t offset, size_t count) { - struct device *dev = to_dev(kobj); + struct device *dev = kobj_to_dev(kobj); struct firmware_priv *fw_priv = to_firmware_priv(dev); struct firmware *fw; ssize_t ret_count; @@ -384,7 +382,7 @@ static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj, struct bin_attribute *bin_attr, char *buffer, loff_t offset, size_t count) { - struct device *dev = to_dev(kobj); + struct device *dev = kobj_to_dev(kobj); struct firmware_priv *fw_priv = to_firmware_priv(dev); struct firmware *fw; ssize_t retval; -- cgit v1.1 From eed5d2150752bd08b22333d739f3120151773d28 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 12 Jul 2012 11:51:48 +0200 Subject: PM / Runtime: Do not increment device usage counts before probing The pm_runtime_get_noresume() calls before really_probe() and before executing __device_attach() for each driver on the device's bus cause problems to happen if probing fails and if the driver has enabled runtime PM for the device in its .probe() callback. Namely, in that case, if the device has been resumed by the driver after enabling its runtime PM and if it turns out that .probe() should return an error, the driver is supposed to suspend the device and disable its runtime PM before exiting .probe(). However, because the device's runtime PM usage counter was incremented by the core before calling .probe(), the driver's attempt to suspend the device will not succeed and the device will remain in the full-power state after the failing .probe() has returned. To fix this issue, remove the pm_runtime_get_noresume() calls from driver_probe_device() and from device_attach() and replace the corresponding pm_runtime_put_sync() calls with pm_runtime_idle() to preserve the existing behavior (which is to check if the device is idle and to suspend it eventually in that case after probing). Reported-and-tested-by: Kevin Hilman Reviewed-by: Kevin Hilman Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman --- drivers/base/dd.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/dd.c b/drivers/base/dd.c index 9b0aca4..e3bbed8 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -369,10 +369,9 @@ int driver_probe_device(struct device_driver *drv, struct device *dev) pr_debug("bus: '%s': %s: matched device %s with driver %s\n", drv->bus->name, __func__, dev_name(dev), drv->name); - pm_runtime_get_noresume(dev); pm_runtime_barrier(dev); ret = really_probe(dev, drv); - pm_runtime_put_sync(dev); + pm_runtime_idle(dev); return ret; } @@ -419,9 +418,8 @@ int device_attach(struct device *dev) ret = 0; } } else { - pm_runtime_get_noresume(dev); ret = bus_for_each_drv(dev->bus, NULL, dev, __device_attach); - pm_runtime_put_sync(dev); + pm_runtime_idle(dev); } out_unlock: device_unlock(dev); -- cgit v1.1 From a14af325641794d1ce8e676e9c4967342349195c Mon Sep 17 00:00:00 2001 From: Sebastian Ott Date: Tue, 17 Jul 2012 10:39:10 +0200 Subject: driver core: don't trigger uevent after failure Do not send the uevent if driver_add_groups failed. Reported-by: Ming Lei Signed-off-by: Sebastian Ott Signed-off-by: Greg Kroah-Hartman --- drivers/base/driver.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/driver.c b/drivers/base/driver.c index 1b500d6..974e301 100644 --- a/drivers/base/driver.c +++ b/drivers/base/driver.c @@ -185,9 +185,10 @@ int driver_register(struct device_driver *drv) if (ret) return ret; ret = driver_add_groups(drv, drv->groups); - if (ret) + if (ret) { bus_remove_driver(drv); - + return ret; + } kobject_uevent(&drv->p->kobj, KOBJ_ADD); return ret; -- cgit v1.1