From 663336ee2628096df0ce2b546b148cb74b5249fe Mon Sep 17 00:00:00 2001 From: Joe Perches Date: Wed, 9 May 2018 08:15:46 -0700 Subject: device: Add #define dev_fmt similar to #define pr_fmt Add a prefixing macro to dev_ uses similar to the pr_fmt prefixing macro used in pr_ calls. This can help avoid some string duplication in dev_ uses. The default, like pr_fmt, is an empty #define dev_fmt(fmt) fmt Rename the existing dev_ functions to _dev_ and introduce #define dev_ _dev_ macros that use the new #define dev_fmt Miscellanea: o Consistently use #defines with fmt, ... and ##__VA_ARGS__ o Remove unnecessary externs Signed-off-by: Joe Perches Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'drivers/base/core.c') diff --git a/drivers/base/core.c b/drivers/base/core.c index df3e1a44707a..ceb8ce90aebb 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -3002,12 +3002,12 @@ void func(const struct device *dev, const char *fmt, ...) \ } \ EXPORT_SYMBOL(func); -define_dev_printk_level(dev_emerg, KERN_EMERG); -define_dev_printk_level(dev_alert, KERN_ALERT); -define_dev_printk_level(dev_crit, KERN_CRIT); -define_dev_printk_level(dev_err, KERN_ERR); -define_dev_printk_level(dev_warn, KERN_WARNING); -define_dev_printk_level(dev_notice, KERN_NOTICE); +define_dev_printk_level(_dev_emerg, KERN_EMERG); +define_dev_printk_level(_dev_alert, KERN_ALERT); +define_dev_printk_level(_dev_crit, KERN_CRIT); +define_dev_printk_level(_dev_err, KERN_ERR); +define_dev_printk_level(_dev_warn, KERN_WARNING); +define_dev_printk_level(_dev_notice, KERN_NOTICE); define_dev_printk_level(_dev_info, KERN_INFO); #endif -- cgit v1.2.3 From 46d3a03781ea70e25360660ac53bbb838de11c97 Mon Sep 17 00:00:00 2001 From: Shaokun Zhang Date: Sun, 15 Jul 2018 18:08:56 +0800 Subject: driver core: remove unnecessary function extern declare device_private_init is called only in core.c, extern declare is unnecessary and make it static. Cc: Greg Kroah-Hartman Cc: "Rafael J. Wysocki" Signed-off-by: Shaokun Zhang Signed-off-by: Greg Kroah-Hartman --- drivers/base/base.h | 2 -- drivers/base/core.c | 2 +- 2 files changed, 1 insertion(+), 3 deletions(-) (limited to 'drivers/base/core.c') diff --git a/drivers/base/base.h b/drivers/base/base.h index a75c3025fb78..7a419a7a6235 100644 --- a/drivers/base/base.h +++ b/drivers/base/base.h @@ -84,8 +84,6 @@ struct device_private { #define to_device_private_bus(obj) \ container_of(obj, struct device_private, knode_bus) -extern int device_private_init(struct device *dev); - /* initialisation functions */ extern int devices_init(void); extern int buses_init(void); diff --git a/drivers/base/core.c b/drivers/base/core.c index ceb8ce90aebb..9a6c71038616 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -1736,7 +1736,7 @@ static void device_remove_sys_dev_entry(struct device *dev) } } -int device_private_init(struct device *dev) +static int device_private_init(struct device *dev) { dev->p = kzalloc(sizeof(*dev->p), GFP_KERNEL); if (!dev->p) -- cgit v1.2.3 From 726e41097920a73e4c7c33385dcc0debb1281e18 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Tue, 10 Jul 2018 10:29:10 +1000 Subject: drivers: core: Remove glue dirs from sysfs earlier For devices with a class, we create a "glue" directory between the parent device and the new device with the class name. This directory is never "explicitely" removed when empty however, this is left to the implicit sysfs removal done by kobject_release() when the object loses its last reference via kobject_put(). This is problematic because as long as it's not been removed from sysfs, it is still present in the class kset and in sysfs directory structure. The presence in the class kset exposes a use after free bug fixed by the previous patch, but the presence in sysfs means that until the kobject is released, which can take a while (especially with kobject debugging), any attempt at re-creating such as binding a new device for that class/parent pair, will result in a sysfs duplicate file name error. This fixes it by instead doing an explicit kobject_del() when the glue dir is empty, by keeping track of the number of child devices of the gluedir. This is made easy by the fact that all glue dir operations are done with a global mutex, and there's already a function (cleanup_glue_dir) called in all the right places taking that mutex that can be enhanced for this. It appears that this was in fact the intent of the function, but the implementation was wrong. Signed-off-by: Benjamin Herrenschmidt Acked-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 2 ++ include/linux/kobject.h | 17 +++++++++++++++++ 2 files changed, 19 insertions(+) (limited to 'drivers/base/core.c') diff --git a/drivers/base/core.c b/drivers/base/core.c index 9a6c71038616..cf8c605ec32e 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -1597,6 +1597,8 @@ static void cleanup_glue_dir(struct device *dev, struct kobject *glue_dir) return; mutex_lock(&gdp_mutex); + if (!kobject_has_children(glue_dir)) + kobject_del(glue_dir); kobject_put(glue_dir); mutex_unlock(&gdp_mutex); } diff --git a/include/linux/kobject.h b/include/linux/kobject.h index 7f6f93c3df9c..270b40515e79 100644 --- a/include/linux/kobject.h +++ b/include/linux/kobject.h @@ -116,6 +116,23 @@ extern void kobject_put(struct kobject *kobj); extern const void *kobject_namespace(struct kobject *kobj); extern char *kobject_get_path(struct kobject *kobj, gfp_t flag); +/** + * kobject_has_children - Returns whether a kobject has children. + * @kobj: the object to test + * + * This will return whether a kobject has other kobjects as children. + * + * It does NOT account for the presence of attribute files, only sub + * directories. It also assumes there is no concurrent addition or + * removal of such children, and thus relies on external locking. + */ +static inline bool kobject_has_children(struct kobject *kobj) +{ + WARN_ON_ONCE(kref_read(&kobj->kref) == 0); + + return kobj->sd && kobj->sd->dir.subdirs; +} + struct kobj_type { void (*release)(struct kobject *kobj); const struct sysfs_ops *sysfs_ops; -- cgit v1.2.3 From 3297c8fc65af5d40501ea7cddff1b195cae57e4e Mon Sep 17 00:00:00 2001 From: Pingfan Liu Date: Thu, 19 Jul 2018 13:14:58 +0800 Subject: drivers/base: stop new probing during shutdown There is a race window in device_shutdown(), which may cause -1. parent device shut down before child or -2. no shutdown on a new probing device. For 1st, taking the following scenario: device_shutdown new plugin device list_del_init(parent_dev); spin_unlock(list_lock); device_add(child) probe child shutdown parent_dev --> now child is on the tail of devices_kset For 2nd, taking the following scenario: device_shutdown new plugin device device_add(dev) device_lock(dev); ... device_unlock(dev); probe dev --> now, the new occurred dev has no opportunity to shutdown To fix this race issue, just prevent the new probing request. With this logic, device_shutdown() is more similar to dpm_prepare(). Signed-off-by: Pingfan Liu Reviewed-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/base/core.c') diff --git a/drivers/base/core.c b/drivers/base/core.c index cf8c605ec32e..5411af447418 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -2811,6 +2811,9 @@ void device_shutdown(void) { struct device *dev, *parent; + wait_for_device_probe(); + device_block_probing(); + spin_lock(&devices_kset->list_lock); /* * Walk the devices list backward, shutting down each in turn. -- cgit v1.2.3 From e16f4f3e0b7daecd48d4f944ab4147c1a6cb16a8 Mon Sep 17 00:00:00 2001 From: Benjamin Gaignard Date: Mon, 16 Jul 2018 13:37:44 +0200 Subject: base: core: Remove WARN_ON from link dependencies check In some cases the link between between customer and supplier already exist, for example when a device use its parent as a supplier. Do not warn about already existing dependencies because device_link_add() takes care of this case. Link: http://lkml.kernel.org/r/20180709111753eucas1p1f32e66fb2f7ea3216097cd72a132355d~-rzycA5Rg0378203782eucas1p1C@eucas1p1.samsung.com Reported-by: Marek Szyprowski Reviewed-by: Mark Brown Signed-off-by: Benjamin Gaignard Reviewed-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/base/core.c') diff --git a/drivers/base/core.c b/drivers/base/core.c index 5411af447418..2300d834d11f 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -105,7 +105,7 @@ static int device_is_dependent(struct device *dev, void *target) struct device_link *link; int ret; - if (WARN_ON(dev == target)) + if (dev == target) return 1; ret = device_for_each_child(dev, target, device_is_dependent); @@ -113,7 +113,7 @@ static int device_is_dependent(struct device *dev, void *target) return ret; list_for_each_entry(link, &dev->links.consumers, s_node) { - if (WARN_ON(link->consumer == target)) + if (link->consumer == target) return 1; ret = device_is_dependent(link->consumer, target); -- cgit v1.2.3