From 32ffed055dcee17f6705f545b069e44a66067808 Mon Sep 17 00:00:00 2001 From: Jiasheng Jiang Date: Wed, 5 Feb 2025 00:43:43 +0000 Subject: regmap-irq: Add missing kfree() Add kfree() for "d->main_status_buf" to the error-handling path to prevent a memory leak. Fixes: a2d21848d921 ("regmap: regmap-irq: Add main status register support") Cc: stable@vger.kernel.org # v5.1+ Signed-off-by: Jiasheng Jiang Link: https://patch.msgid.link/20250205004343.14413-1-jiashengjiangcool@gmail.com Signed-off-by: Mark Brown --- drivers/base/regmap/regmap-irq.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/base') diff --git a/drivers/base/regmap/regmap-irq.c b/drivers/base/regmap/regmap-irq.c index 0bcd81389a29..978613407ea3 100644 --- a/drivers/base/regmap/regmap-irq.c +++ b/drivers/base/regmap/regmap-irq.c @@ -906,6 +906,7 @@ err_alloc: kfree(d->wake_buf); kfree(d->mask_buf_def); kfree(d->mask_buf); + kfree(d->main_status_buf); kfree(d->status_buf); kfree(d->status_reg_buf); if (d->config_buf) { @@ -981,6 +982,7 @@ void regmap_del_irq_chip(int irq, struct regmap_irq_chip_data *d) kfree(d->wake_buf); kfree(d->mask_buf_def); kfree(d->mask_buf); + kfree(d->main_status_buf); kfree(d->status_reg_buf); kfree(d->status_buf); if (d->config_buf) { -- cgit v1.2.3 From 7585946243d614bd2cd4e13377be2c711c9539e0 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sat, 8 Feb 2025 18:54:28 +0100 Subject: PM: sleep: core: Restrict power.set_active propagation Commit 3775fc538f53 ("PM: sleep: core: Synchronize runtime PM status of parents and children") exposed an issue related to simple_pm_bus_pm_ops that uses pm_runtime_force_suspend() and pm_runtime_force_resume() as bus type PM callbacks for the noirq phases of system-wide suspend and resume. The problem is that pm_runtime_force_suspend() does not distinguish runtime-suspended devices from devices for which runtime PM has never been enabled, so if it sees a device with runtime PM status set to RPM_ACTIVE, it will assume that runtime PM is enabled for that device and so it will attempt to suspend it with the help of its runtime PM callbacks which may not be ready for that. As it turns out, this causes simple_pm_bus_runtime_suspend() to crash due to a NULL pointer dereference. Another problem related to the above commit and simple_pm_bus_pm_ops is that setting runtime PM status of a device handled by the latter to RPM_ACTIVE will actually prevent it from being resumed because pm_runtime_force_resume() only resumes devices with runtime PM status set to RPM_SUSPENDED. To mitigate these issues, do not allow power.set_active to propagate beyond the parent of the device with DPM_FLAG_SMART_SUSPEND set that will need to be resumed, which should be a sufficient stop-gap for the time being, but they will need to be properly addressed in the future because in general during system-wide resume it is necessary to resume all devices in a dependency chain in which at least one device is going to be resumed. Fixes: 3775fc538f53 ("PM: sleep: core: Synchronize runtime PM status of parents and children") Closes: https://lore.kernel.org/linux-pm/1c2433d4-7e0f-4395-b841-b8eac7c25651@nvidia.com/ Reported-by: Jon Hunter Tested-by: Johan Hovold Signed-off-by: Rafael J. Wysocki Link: https://patch.msgid.link/6137505.lOV4Wx5bFT@rjwysocki.net --- drivers/base/power/main.c | 21 +++++++++------------ 1 file changed, 9 insertions(+), 12 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index d497d448e4b2..40e1d8d8a589 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -1191,24 +1191,18 @@ static pm_message_t resume_event(pm_message_t sleep_state) return PMSG_ON; } -static void dpm_superior_set_must_resume(struct device *dev, bool set_active) +static void dpm_superior_set_must_resume(struct device *dev) { struct device_link *link; int idx; - if (dev->parent) { + if (dev->parent) dev->parent->power.must_resume = true; - if (set_active) - dev->parent->power.set_active = true; - } idx = device_links_read_lock(); - list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node) { + list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node) link->supplier->power.must_resume = true; - if (set_active) - link->supplier->power.set_active = true; - } device_links_read_unlock(idx); } @@ -1287,9 +1281,12 @@ Skip: dev->power.must_resume = true; if (dev->power.must_resume) { - dev->power.set_active = dev->power.set_active || - dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND); - dpm_superior_set_must_resume(dev, dev->power.set_active); + if (dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND)) { + dev->power.set_active = true; + if (dev->parent && !dev->parent->power.ignore_children) + dev->parent->power.set_active = true; + } + dpm_superior_set_must_resume(dev); } Complete: -- cgit v1.2.3 From 35fa2d88ca9481e5caf533d58b99ca259c63b2fe Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Mon, 10 Feb 2025 13:30:25 +0100 Subject: driver core: add a faux bus for use when a simple device/bus is needed MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Many drivers abuse the platform driver/bus system as it provides a simple way to create and bind a device to a driver-specific set of probe/release functions. Instead of doing that, and wasting all of the memory associated with a platform device, here is a "faux" bus that can be used instead. Reviewed-by: Jonathan Cameron Reviewed-by: Danilo Krummrich Reviewed-by: Lyude Paul Reviewed-by: Thomas Weißschuh Reviewed-by: Zijun Hu Link: https://lore.kernel.org/r/2025021026-atlantic-gibberish-3f0c@gregkh Signed-off-by: Greg Kroah-Hartman --- drivers/base/Makefile | 2 +- drivers/base/base.h | 1 + drivers/base/faux.c | 232 ++++++++++++++++++++++++++++++++++++++++++++++++++ drivers/base/init.c | 1 + 4 files changed, 235 insertions(+), 1 deletion(-) create mode 100644 drivers/base/faux.c (limited to 'drivers/base') diff --git a/drivers/base/Makefile b/drivers/base/Makefile index 7fb21768ca36..8074a10183dc 100644 --- a/drivers/base/Makefile +++ b/drivers/base/Makefile @@ -6,7 +6,7 @@ obj-y := component.o core.o bus.o dd.o syscore.o \ cpu.o firmware.o init.o map.o devres.o \ attribute_container.o transport_class.o \ topology.o container.o property.o cacheinfo.o \ - swnode.o + swnode.o faux.o obj-$(CONFIG_AUXILIARY_BUS) += auxiliary.o obj-$(CONFIG_DEVTMPFS) += devtmpfs.o obj-y += power/ diff --git a/drivers/base/base.h b/drivers/base/base.h index 8cf04a557bdb..0042e4774b0c 100644 --- a/drivers/base/base.h +++ b/drivers/base/base.h @@ -137,6 +137,7 @@ int hypervisor_init(void); static inline int hypervisor_init(void) { return 0; } #endif int platform_bus_init(void); +int faux_bus_init(void); void cpu_dev_init(void); void container_dev_init(void); #ifdef CONFIG_AUXILIARY_BUS diff --git a/drivers/base/faux.c b/drivers/base/faux.c new file mode 100644 index 000000000000..531e9d789ee0 --- /dev/null +++ b/drivers/base/faux.c @@ -0,0 +1,232 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2025 Greg Kroah-Hartman + * Copyright (c) 2025 The Linux Foundation + * + * A "simple" faux bus that allows devices to be created and added + * automatically to it. This is to be used whenever you need to create a + * device that is not associated with any "real" system resources, and do + * not want to have to deal with a bus/driver binding logic. It is + * intended to be very simple, with only a create and a destroy function + * available. + */ +#include +#include +#include +#include +#include +#include +#include "base.h" + +/* + * Internal wrapper structure so we can hold a pointer to the + * faux_device_ops for this device. + */ +struct faux_object { + struct faux_device faux_dev; + const struct faux_device_ops *faux_ops; +}; +#define to_faux_object(dev) container_of_const(dev, struct faux_object, faux_dev.dev) + +static struct device faux_bus_root = { + .init_name = "faux", +}; + +static int faux_match(struct device *dev, const struct device_driver *drv) +{ + /* Match always succeeds, we only have one driver */ + return 1; +} + +static int faux_probe(struct device *dev) +{ + struct faux_object *faux_obj = to_faux_object(dev); + struct faux_device *faux_dev = &faux_obj->faux_dev; + const struct faux_device_ops *faux_ops = faux_obj->faux_ops; + int ret = 0; + + if (faux_ops && faux_ops->probe) + ret = faux_ops->probe(faux_dev); + + return ret; +} + +static void faux_remove(struct device *dev) +{ + struct faux_object *faux_obj = to_faux_object(dev); + struct faux_device *faux_dev = &faux_obj->faux_dev; + const struct faux_device_ops *faux_ops = faux_obj->faux_ops; + + if (faux_ops && faux_ops->remove) + faux_ops->remove(faux_dev); +} + +static const struct bus_type faux_bus_type = { + .name = "faux", + .match = faux_match, + .probe = faux_probe, + .remove = faux_remove, +}; + +static struct device_driver faux_driver = { + .name = "faux_driver", + .bus = &faux_bus_type, + .probe_type = PROBE_FORCE_SYNCHRONOUS, +}; + +static void faux_device_release(struct device *dev) +{ + struct faux_object *faux_obj = to_faux_object(dev); + + kfree(faux_obj); +} + +/** + * faux_device_create_with_groups - Create and register with the driver + * core a faux device and populate the device with an initial + * set of sysfs attributes. + * @name: The name of the device we are adding, must be unique for + * all faux devices. + * @parent: Pointer to a potential parent struct device. If set to + * NULL, the device will be created in the "root" of the faux + * device tree in sysfs. + * @faux_ops: struct faux_device_ops that the new device will call back + * into, can be NULL. + * @groups: The set of sysfs attributes that will be created for this + * device when it is registered with the driver core. + * + * Create a new faux device and register it in the driver core properly. + * If present, callbacks in @faux_ops will be called with the device that + * for the caller to do something with at the proper time given the + * device's lifecycle. + * + * Note, when this function is called, the functions specified in struct + * faux_ops can be called before the function returns, so be prepared for + * everything to be properly initialized before that point in time. + * + * Return: + * * NULL if an error happened with creating the device + * * pointer to a valid struct faux_device that is registered with sysfs + */ +struct faux_device *faux_device_create_with_groups(const char *name, + struct device *parent, + const struct faux_device_ops *faux_ops, + const struct attribute_group **groups) +{ + struct faux_object *faux_obj; + struct faux_device *faux_dev; + struct device *dev; + int ret; + + faux_obj = kzalloc(sizeof(*faux_obj), GFP_KERNEL); + if (!faux_obj) + return NULL; + + /* Save off the callbacks so we can use them in the future */ + faux_obj->faux_ops = faux_ops; + + /* Initialize the device portion and register it with the driver core */ + faux_dev = &faux_obj->faux_dev; + dev = &faux_dev->dev; + + device_initialize(dev); + dev->release = faux_device_release; + if (parent) + dev->parent = parent; + else + dev->parent = &faux_bus_root; + dev->bus = &faux_bus_type; + dev->groups = groups; + dev_set_name(dev, "%s", name); + + ret = device_add(dev); + if (ret) { + pr_err("%s: device_add for faux device '%s' failed with %d\n", + __func__, name, ret); + put_device(dev); + return NULL; + } + + return faux_dev; +} +EXPORT_SYMBOL_GPL(faux_device_create_with_groups); + +/** + * faux_device_create - create and register with the driver core a faux device + * @name: The name of the device we are adding, must be unique for all + * faux devices. + * @parent: Pointer to a potential parent struct device. If set to + * NULL, the device will be created in the "root" of the faux + * device tree in sysfs. + * @faux_ops: struct faux_device_ops that the new device will call back + * into, can be NULL. + * + * Create a new faux device and register it in the driver core properly. + * If present, callbacks in @faux_ops will be called with the device that + * for the caller to do something with at the proper time given the + * device's lifecycle. + * + * Note, when this function is called, the functions specified in struct + * faux_ops can be called before the function returns, so be prepared for + * everything to be properly initialized before that point in time. + * + * Return: + * * NULL if an error happened with creating the device + * * pointer to a valid struct faux_device that is registered with sysfs + */ +struct faux_device *faux_device_create(const char *name, + struct device *parent, + const struct faux_device_ops *faux_ops) +{ + return faux_device_create_with_groups(name, parent, faux_ops, NULL); +} +EXPORT_SYMBOL_GPL(faux_device_create); + +/** + * faux_device_destroy - destroy a faux device + * @faux_dev: faux device to destroy + * + * Unregisters and cleans up a device that was created with a call to + * faux_device_create() + */ +void faux_device_destroy(struct faux_device *faux_dev) +{ + struct device *dev = &faux_dev->dev; + + if (!faux_dev) + return; + + device_del(dev); + + /* The final put_device() will clean up the memory we allocated for this device. */ + put_device(dev); +} +EXPORT_SYMBOL_GPL(faux_device_destroy); + +int __init faux_bus_init(void) +{ + int ret; + + ret = device_register(&faux_bus_root); + if (ret) { + put_device(&faux_bus_root); + return ret; + } + + ret = bus_register(&faux_bus_type); + if (ret) + goto error_bus; + + ret = driver_register(&faux_driver); + if (ret) + goto error_driver; + + return ret; + +error_driver: + bus_unregister(&faux_bus_type); + +error_bus: + device_unregister(&faux_bus_root); + return ret; +} diff --git a/drivers/base/init.c b/drivers/base/init.c index c4954835128c..9d2b06d65dfc 100644 --- a/drivers/base/init.c +++ b/drivers/base/init.c @@ -32,6 +32,7 @@ void __init driver_init(void) /* These are also core pieces, but must come after the * core core pieces. */ + faux_bus_init(); of_core_init(); platform_bus_init(); auxiliary_bus_init(); -- cgit v1.2.3