diff options
32 files changed, 856 insertions, 233 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-platform b/Documentation/ABI/testing/sysfs-bus-platform index 5172a6124b27..194ca700e962 100644 --- a/Documentation/ABI/testing/sysfs-bus-platform +++ b/Documentation/ABI/testing/sysfs-bus-platform @@ -18,3 +18,13 @@ Description: devices to opt-out of driver binding using a driver_override name such as "none". Only a single driver may be specified in the override, there is no support for parsing delimiters. + +What: /sys/bus/platform/devices/.../numa_node +Date: June 2020 +Contact: Barry Song <song.bao.hua@hisilicon.com> +Description: + This file contains the NUMA node to which the platform device + is attached. It won't be visible if the node is unknown. The + value comes from an ACPI _PXM method or a similar firmware + source. Initial users for this file would be devices like + arm smmu which are populated by arm64 acpi_iort. diff --git a/Documentation/ABI/testing/sysfs-class-devlink b/Documentation/ABI/testing/sysfs-class-devlink new file mode 100644 index 000000000000..64791b65c9a3 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-class-devlink @@ -0,0 +1,126 @@ +What: /sys/class/devlink/.../ +Date: May 2020 +Contact: Saravana Kannan <saravanak@google.com> +Description: + Provide a place in sysfs for the device link objects in the + kernel at any given time. The name of a device link directory, + denoted as ... above, is of the form <supplier>--<consumer> + where <supplier> is the supplier device name and <consumer> is + the consumer device name. + +What: /sys/class/devlink/.../auto_remove_on +Date: May 2020 +Contact: Saravana Kannan <saravanak@google.com> +Description: + This file indicates if the device link will ever be + automatically removed by the driver core when the consumer and + supplier devices themselves are still present. + + This will be one of the following strings: + + 'consumer unbind' + 'supplier unbind' + 'never' + + 'consumer unbind' means the device link will be removed when + the consumer's driver is unbound from the consumer device. + + 'supplier unbind' means the device link will be removed when + the supplier's driver is unbound from the supplier device. + + 'never' means the device link will not be automatically removed + when as long as the supplier and consumer devices themselves + are still present. + +What: /sys/class/devlink/.../consumer +Date: May 2020 +Contact: Saravana Kannan <saravanak@google.com> +Description: + This file is a symlink to the consumer device's sysfs directory. + +What: /sys/class/devlink/.../runtime_pm +Date: May 2020 +Contact: Saravana Kannan <saravanak@google.com> +Description: + This file indicates if the device link has any impact on the + runtime power management behavior of the consumer and supplier + devices. For example: Making sure the supplier doesn't enter + runtime suspend while the consumer is active. + + This will be one of the following strings: + + '0' - Does not affect runtime power management + '1' - Affects runtime power management + +What: /sys/class/devlink/.../status +Date: May 2020 +Contact: Saravana Kannan <saravanak@google.com> +Description: + This file indicates the status of the device link. The status + of a device link is affected by whether the supplier and + consumer devices have been bound to their corresponding + drivers. The status of a device link also affects the binding + and unbinding of the supplier and consumer devices with their + drivers and also affects whether the software state of the + supplier device is synced with the hardware state of the + supplier device after boot up. + See also: sysfs-devices-state_synced. + + This will be one of the following strings: + + 'not tracked' + 'dormant' + 'available' + 'consumer probing' + 'active' + 'supplier unbinding' + 'unknown' + + 'not tracked' means this device link does not track the status + and has no impact on the binding, unbinding and syncing the + hardware and software device state. + + 'dormant' means the supplier and the consumer devices have not + bound to their driver. + + 'available' means the supplier has bound to its driver and is + available to supply resources to the consumer device. + + 'consumer probing' means the consumer device is currently + trying to bind to its driver. + + 'active' means the supplier and consumer devices have both + bound successfully to their drivers. + + 'supplier unbinding' means the supplier devices is currently in + the process of unbinding from its driver. + + 'unknown' means the state of the device link is not any of the + above. If this is ever the value, there's a bug in the kernel. + +What: /sys/class/devlink/.../supplier +Date: May 2020 +Contact: Saravana Kannan <saravanak@google.com> +Description: + This file is a symlink to the supplier device's sysfs directory. + +What: /sys/class/devlink/.../sync_state_only +Date: May 2020 +Contact: Saravana Kannan <saravanak@google.com> +Description: + This file indicates if the device link is limited to only + affecting the syncing of the hardware and software state of the + supplier device. + + This will be one of the following strings: + + '0' + '1' - Affects runtime power management + + '0' means the device link can affect other device behaviors + like binding/unbinding, suspend/resume, runtime power + management, etc. + + '1' means the device link will only affect the syncing of + hardware and software state of the supplier device after boot + up and doesn't not affect other behaviors of the devices. diff --git a/Documentation/ABI/testing/sysfs-devices-consumer b/Documentation/ABI/testing/sysfs-devices-consumer new file mode 100644 index 000000000000..1f06d74d1c3c --- /dev/null +++ b/Documentation/ABI/testing/sysfs-devices-consumer @@ -0,0 +1,8 @@ +What: /sys/devices/.../consumer:<consumer> +Date: May 2020 +Contact: Saravana Kannan <saravanak@google.com> +Description: + The /sys/devices/.../consumer:<consumer> are symlinks to device + links where this device is the supplier. <consumer> denotes the + name of the consumer in that device link. There can be zero or + more of these symlinks for a given device. diff --git a/Documentation/ABI/testing/sysfs-devices-state_synced b/Documentation/ABI/testing/sysfs-devices-state_synced new file mode 100644 index 000000000000..0c922d7d02fc --- /dev/null +++ b/Documentation/ABI/testing/sysfs-devices-state_synced @@ -0,0 +1,24 @@ +What: /sys/devices/.../state_synced +Date: May 2020 +Contact: Saravana Kannan <saravanak@google.com> +Description: + The /sys/devices/.../state_synced attribute is only present for + devices whose bus types or driver provides the .sync_state() + callback. The number read from it (0 or 1) reflects the value + of the device's 'state_synced' field. A value of 0 means the + .sync_state() callback hasn't been called yet. A value of 1 + means the .sync_state() callback has been called. + + Generally, if a device has sync_state() support and has some of + the resources it provides enabled at the time the kernel starts + (Eg: enabled by hardware reset or bootloader or anything that + run before the kernel starts), then it'll keep those resources + enabled and in a state that's compatible with the state they + were in at the start of the kernel. The device will stop doing + this only when the sync_state() callback has been called -- + which happens only when all its consumer devices are registered + and have probed successfully. Resources that were left disabled + at the time the kernel starts are not affected or limited in + any way by sync_state() callbacks. + + diff --git a/Documentation/ABI/testing/sysfs-devices-supplier b/Documentation/ABI/testing/sysfs-devices-supplier new file mode 100644 index 000000000000..a919e0db5e90 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-devices-supplier @@ -0,0 +1,8 @@ +What: /sys/devices/.../supplier:<supplier> +Date: May 2020 +Contact: Saravana Kannan <saravanak@google.com> +Description: + The /sys/devices/.../supplier:<supplier> are symlinks to device + links where this device is the consumer. <supplier> denotes the + name of the supplier in that device link. There can be zero or + more of these symlinks for a given device. diff --git a/Documentation/ABI/testing/sysfs-devices-waiting_for_supplier b/Documentation/ABI/testing/sysfs-devices-waiting_for_supplier new file mode 100644 index 000000000000..59d073d20db6 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-devices-waiting_for_supplier @@ -0,0 +1,17 @@ +What: /sys/devices/.../waiting_for_supplier +Date: May 2020 +Contact: Saravana Kannan <saravanak@google.com> +Description: + The /sys/devices/.../waiting_for_supplier attribute is only + present when fw_devlink kernel command line option is enabled + and is set to something stricter than "permissive". It is + removed once a device probes successfully (because the + information is no longer relevant). The number read from it (0 + or 1) reflects whether the device is waiting for one or more + suppliers to be added and then linked to using device links + before the device can probe. + + A value of 0 means the device is not waiting for any suppliers + to be added before it can probe. A value of 1 means the device + is waiting for one or more suppliers to be added before it can + probe. diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index fb95fad81c79..6766a308ad96 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -827,6 +827,21 @@ useful to also enable the page_owner functionality. on: enable the feature + debugfs= [KNL] This parameter enables what is exposed to userspace + and debugfs internal clients. + Format: { on, no-mount, off } + on: All functions are enabled. + no-mount: + Filesystem is not registered but kernel clients can + access APIs and a crashkernel can be used to read + its content. There is nothing to mount. + off: Filesystem is not registered and clients + get a -EPERM as result when trying to register files + or directories within debugfs. + This is equivalent of the runtime functionality if + debugfs was not enabled in the kernel at all. + Default value is set in build-time with a kernel configuration. + debugpat [X86] Enable PAT debugging decnet.addr= [HW,NET] diff --git a/Documentation/driver-api/driver-model/platform.rst b/Documentation/driver-api/driver-model/platform.rst index 334dd4071ae4..1fe5c6c6199c 100644 --- a/Documentation/driver-api/driver-model/platform.rst +++ b/Documentation/driver-api/driver-model/platform.rst @@ -108,7 +108,7 @@ field to hold additional information. Embedded systems frequently need one or more clocks for platform devices, which are normally kept off until they're actively needed (to save power). -System setup also associates those clocks with the device, so that that +System setup also associates those clocks with the device, so that calls to clk_get(&pdev->dev, clock_name) return them as needed. diff --git a/drivers/base/core.c b/drivers/base/core.c index 05d414e9e8a4..4d05868d9356 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -236,6 +236,210 @@ void device_pm_move_to_tail(struct device *dev) device_links_read_unlock(idx); } +#define to_devlink(dev) container_of((dev), struct device_link, link_dev) + +static ssize_t status_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + char *status; + + switch (to_devlink(dev)->status) { + case DL_STATE_NONE: + status = "not tracked"; break; + case DL_STATE_DORMANT: + status = "dormant"; break; + case DL_STATE_AVAILABLE: + status = "available"; break; + case DL_STATE_CONSUMER_PROBE: + status = "consumer probing"; break; + case DL_STATE_ACTIVE: + status = "active"; break; + case DL_STATE_SUPPLIER_UNBIND: + status = "supplier unbinding"; break; + default: + status = "unknown"; break; + } + return sprintf(buf, "%s\n", status); +} +static DEVICE_ATTR_RO(status); + +static ssize_t auto_remove_on_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct device_link *link = to_devlink(dev); + char *str; + + if (link->flags & DL_FLAG_AUTOREMOVE_SUPPLIER) + str = "supplier unbind"; + else if (link->flags & DL_FLAG_AUTOREMOVE_CONSUMER) + str = "consumer unbind"; + else + str = "never"; + + return sprintf(buf, "%s\n", str); +} +static DEVICE_ATTR_RO(auto_remove_on); + +static ssize_t runtime_pm_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct device_link *link = to_devlink(dev); + + return sprintf(buf, "%d\n", !!(link->flags & DL_FLAG_PM_RUNTIME)); +} +static DEVICE_ATTR_RO(runtime_pm); + +static ssize_t sync_state_only_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct device_link *link = to_devlink(dev); + + return sprintf(buf, "%d\n", !!(link->flags & DL_FLAG_SYNC_STATE_ONLY)); +} +static DEVICE_ATTR_RO(sync_state_only); + +static struct attribute *devlink_attrs[] = { + &dev_attr_status.attr, + &dev_attr_auto_remove_on.attr, + &dev_attr_runtime_pm.attr, + &dev_attr_sync_state_only.attr, + NULL, +}; +ATTRIBUTE_GROUPS(devlink); + +static void device_link_free(struct device_link *link) +{ + while (refcount_dec_not_one(&link->rpm_active)) + pm_runtime_put(link->supplier); + + put_device(link->consumer); + put_device(link->supplier); + kfree(link); +} + +#ifdef CONFIG_SRCU +static void __device_link_free_srcu(struct rcu_head *rhead) +{ + device_link_free(container_of(rhead, struct device_link, rcu_head)); +} + +static void devlink_dev_release(struct device *dev) +{ + struct device_link *link = to_devlink(dev); + + call_srcu(&device_links_srcu, &link->rcu_head, __device_link_free_srcu); +} +#else +static void devlink_dev_release(struct device *dev) +{ + device_link_free(to_devlink(dev)); +} +#endif + +static struct class devlink_class = { + .name = "devlink", + .owner = THIS_MODULE, + .dev_groups = devlink_groups, + .dev_release = devlink_dev_release, +}; + +static int devlink_add_symlinks(struct device *dev, + struct class_interface *class_intf) +{ + int ret; + size_t len; + struct device_link *link = to_devlink(dev); + struct device *sup = link->supplier; + struct device *con = link->consumer; + char *buf; + + len = max(strlen(dev_name(sup)), strlen(dev_name(con))); + len += strlen("supplier:") + 1; + buf = kzalloc(len, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + ret = sysfs_create_link(&link->link_dev.kobj, &sup->kobj, "supplier"); + if (ret) + goto out; + + ret = sysfs_create_link(&link->link_dev.kobj, &con->kobj, "consumer"); + if (ret) + goto err_con; + + snprintf(buf, len, "consumer:%s", dev_name(con)); + ret = sysfs_create_link(&sup->kobj, &link->link_dev.kobj, buf); + if (ret) + goto err_con_dev; + + snprintf(buf, len, "supplier:%s", dev_name(sup)); + ret = sysfs_create_link(&con->kobj, &link->link_dev.kobj, buf); + if (ret) + goto err_sup_dev; + + goto out; + +err_sup_dev: + snprintf(buf, len, "consumer:%s", dev_name(con)); + sysfs_remove_link(&sup->kobj, buf); +err_con_dev: + sysfs_remove_link(&link->link_dev.kobj, "consumer"); +err_con: + sysfs_remove_link(&link->link_dev.kobj, "supplier"); +out: + kfree(buf); + return ret; +} + +static void devlink_remove_symlinks(struct device *dev, + struct class_interface *class_intf) +{ + struct device_link *link = to_devlink(dev); + size_t len; + struct device *sup = link->supplier; + struct device *con = link->consumer; + char *buf; + + sysfs_remove_link(&link->link_dev.kobj, "consumer"); + sysfs_remove_link(&link->link_dev.kobj, "supplier"); + + len = max(strlen(dev_name(sup)), strlen(dev_name(con))); + len += strlen("supplier:") + 1; + buf = kzalloc(len, GFP_KERNEL); + if (!buf) { + WARN(1, "Unable to properly free device link symlinks!\n"); + return; + } + + snprintf(buf, len, "supplier:%s", dev_name(sup)); + sysfs_remove_link(&con->kobj, buf); + snprintf(buf, len, "consumer:%s", dev_name(con)); + sysfs_remove_link(&sup->kobj, buf); + kfree(buf); +} + +static struct class_interface devlink_class_intf = { + .class = &devlink_class, + .add_dev = devlink_add_symlinks, + .remove_dev = devlink_remove_symlinks, +}; + +static int __init devlink_class_init(void) +{ + int ret; + + ret = class_register(&devlink_class); + if (ret) + return ret; + + ret = class_interface_register(&devlink_class_intf); + if (ret) + class_unregister(&devlink_class); + + return ret; +} +postcore_initcall(devlink_class_init); + #define DL_MANAGED_LINK_FLAGS (DL_FLAG_AUTOREMOVE_CONSUMER | \ DL_FLAG_AUTOREMOVE_SUPPLIER | \ DL_FLAG_AUTOPROBE_CONSUMER | \ @@ -408,13 +612,6 @@ struct device_link *device_link_add(struct device *consumer, refcount_set(&link->rpm_active, 1); - if (flags & DL_FLAG_PM_RUNTIME) { - if (flags & DL_FLAG_RPM_ACTIVE) - refcount_inc(&link->rpm_active); - - pm_runtime_new_link(consumer); - } - get_device(supplier); link->supplier = supplier; INIT_LIST_HEAD(&link->s_node); @@ -424,6 +621,25 @@ struct device_link *device_link_add(struct device *consumer, link->flags = flags; kref_init(&link->kref); + link->link_dev.class = &devlink_class; + device_set_pm_not_required(&link->link_dev); + dev_set_name(&link->link_dev, "%s--%s", + dev_name(supplier), dev_name(consumer)); + if (device_register(&link->link_dev)) { + put_device(consumer); + put_device(supplier); + kfree(link); + link = NULL; + goto out; + } + + if (flags & DL_FLAG_PM_RUNTIME) { + if (flags & DL_FLAG_RPM_ACTIVE) + refcount_inc(&link->rpm_active); + + pm_runtime_new_link(consumer); + } + /* Determine the initial link state. */ if (flags & DL_FLAG_STATELESS) link->status = DL_STATE_NONE; @@ -539,22 +755,7 @@ static void device_link_add_missing_supplier_links(void) mutex_unlock(&wfs_lock); } -static void device_link_free(struct device_link *link) -{ - while (refcount_dec_not_one(&link->rpm_active)) - pm_runtime_put(link->supplier); - - put_device(link->consumer); - put_device(link->supplier); - kfree(link); -} - #ifdef CONFIG_SRCU -static void __device_link_free_srcu(struct rcu_head *rhead) -{ - device_link_free(container_of(rhead, struct device_link, rcu_head)); -} - static void __device_link_del(struct kref *kref) { struct device_link *link = container_of(kref, struct device_link, kref); @@ -567,7 +768,7 @@ static void __device_link_del(struct kref *kref) list_del_rcu(&link->s_node); list_del_rcu(&link->c_node); - call_srcu(&device_links_srcu, &link->rcu_head, __device_link_free_srcu); + device_unregister(&link->link_dev); } #else /* !CONFIG_SRCU */ static void __device_link_del(struct kref *kref) @@ -582,7 +783,7 @@ static void __device_link_del(struct kref *kref) list_del(&link->s_node); list_del(&link->c_node); - device_link_free(link); + device_unregister(&link->link_dev); } #endif /* !CONFIG_SRCU */ @@ -850,6 +1051,22 @@ static void device_link_drop_managed(struct device_link *link) kref_put(&link->kref, __device_link_del); } +static ssize_t waiting_for_supplier_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + bool val; + + device_lock(dev); + mutex_lock(&wfs_lock); + val = !list_empty(&dev->links.needs_suppliers) + && dev->links.need_for_probe; + mutex_unlock(&wfs_lock); + device_unlock(dev); + return sprintf(buf, "%u\n", val); +} +static DEVICE_ATTR_RO(waiting_for_supplier); + /** * device_links_driver_bound - Update device links after probing its driver. * @dev: Device to update the links for. @@ -874,6 +1091,7 @@ void device_links_driver_bound(struct device *dev) mutex_lock(&wfs_lock); list_del_init(&dev->links.needs_suppliers); mutex_unlock(&wfs_lock); + device_remove_file(dev, &dev_attr_waiting_for_supplier); device_links_write_lock(); @@ -1160,6 +1378,9 @@ static void device_links_purge(struct device *dev) { struct device_link *link, *ln; + if (dev->class == &devlink_class) + return; + mutex_lock(&wfs_lock); list_del(&dev->links.needs_suppliers); mutex_unlock(&wfs_lock); @@ -1969,8 +2190,16 @@ static int device_add_attrs(struct device *dev) goto err_remove_dev_groups; } + if (fw_devlink_flags && !fw_devlink_is_permissive()) { + error = device_create_file(dev, &dev_attr_waiting_for_supplier); + if (error) + goto err_remove_dev_online; + } + return 0; + err_remove_dev_online: + device_remove_file(dev, &dev_attr_online); err_remove_dev_groups: device_remove_groups(dev, dev->groups); err_remove_type_groups: @@ -1988,6 +2217,7 @@ static void device_remove_attrs(struct device *dev) struct class *class = dev->class; const struct device_type *type = dev->type; + device_remove_file(dev, &dev_attr_waiting_for_supplier); device_remove_file(dev, &dev_attr_online); device_remove_groups(dev, dev->groups); diff --git a/drivers/base/dd.c b/drivers/base/dd.c index 48ca81cb8ebc..fce8e35b6367 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -276,7 +276,7 @@ static void deferred_probe_timeout_work_func(struct work_struct *work) list_for_each_entry_safe(private, p, &deferred_probe_pending_list, deferred_probe) dev_info(private->device, "deferred probe pending\n"); - wake_up(&probe_timeout_waitqueue); + wake_up_all(&probe_timeout_waitqueue); } static DECLARE_DELAYED_WORK(deferred_probe_timeout_work, deferred_probe_timeout_work_func); @@ -425,10 +425,9 @@ static void driver_sysfs_remove(struct device *dev) * Allow manual attachment of a driver to a device. * Caller must have already set @dev->driver. * - * Note that this does not modify the bus reference count - * nor take the bus's rwsem. Please verify those are accounted - * for before calling this. (It is ok to call with no other effort - * from a driver's probe() method.) + * Note that this does not modify the bus reference count. + * Please verify that is accounted 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 the device lock held. */ @@ -458,6 +457,18 @@ static void driver_deferred_probe_add_trigger(struct device *dev, driver_deferred_probe_trigger(); } +static ssize_t state_synced_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + bool val; + + device_lock(dev); + val = dev->state_synced; + device_unlock(dev); + return sprintf(buf, "%u\n", val); +} +static DEVICE_ATTR_RO(state_synced); + static int really_probe(struct device *dev, struct device_driver *drv) { int ret = -EPROBE_DEFER; @@ -487,7 +498,8 @@ static int really_probe(struct device *dev, struct device_driver *drv) drv->bus->name, __func__, drv->name, dev_name(dev)); if (!list_empty(&dev->devres_head)) { dev_crit(dev, "Resources present before probing\n"); - return -EBUSY; + ret = -EBUSY; + goto done; } re_probe: @@ -531,9 +543,16 @@ re_probe: goto dev_groups_failed; } + if (dev_has_sync_state(dev) && + device_create_file(dev, &dev_attr_state_synced)) { + dev_err(dev, "state_synced sysfs add failed\n"); + goto dev_sysfs_state_synced_failed; + } + if (test_remove) { test_remove = false; + device_remove_file(dev, &dev_attr_state_synced); device_remove_groups(dev, drv->dev_groups); if (dev->bus->remove) @@ -563,6 +582,8 @@ re_probe: drv->bus->name, __func__, dev_name(dev), drv->name); goto done; +dev_sysfs_state_synced_failed: + device_remove_groups(dev, drv->dev_groups); dev_groups_failed: if (dev->bus->remove) dev->bus->remove(dev); @@ -607,7 +628,7 @@ pinctrl_bind_failed: ret = 0; done: atomic_dec(&probe_count); - wake_up(&probe_waitqueue); + wake_up_all(&probe_waitqueue); return ret; } @@ -1100,6 +1121,7 @@ static void __device_release_driver(struct device *dev, struct device *parent) pm_runtime_put_sync(dev); + device_remove_file(dev, &dev_attr_state_synced); device_remove_groups(dev, drv->dev_groups); if (dev->bus && dev->bus->remove) diff --git a/drivers/base/devres.c b/drivers/base/devres.c index 0bbb328bd17f..ed615d3b9cf1 100644 --- a/drivers/base/devres.c +++ b/drivers/base/devres.c @@ -89,15 +89,23 @@ static struct devres_group * node_to_group(struct devres_node *node) return NULL; } +static bool check_dr_size(size_t size, size_t *tot_size) +{ + /* We must catch any near-SIZE_MAX cases that could overflow. */ + if (unlikely(check_add_overflow(sizeof(struct devres), + size, tot_size))) + return false; + + return true; +} + static __always_inline struct devres * alloc_dr(dr_release_t release, size_t size, gfp_t gfp, int nid) { size_t tot_size; struct devres *dr; - /* We must catch any near-SIZE_MAX cases that could overflow. */ - if (unlikely(check_add_overflow(sizeof(struct devres), size, - &tot_size))) + if (!check_dr_size(size, &tot_size)) return NULL; dr = kmalloc_node_track_caller(tot_size, gfp, nid); @@ -807,10 +815,13 @@ static int devm_kmalloc_match(struct device *dev, void *res, void *data) * RETURNS: * Pointer to allocated memory on success, NULL on failure. */ -void * devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) +void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp) { struct devres *dr; + if (unlikely(!size)) + return ZERO_SIZE_PTR; + /* use raw alloc_dr for kmalloc caller tracing */ dr = alloc_dr(devm_kmal |