diff options
| -rw-r--r-- | drivers/cxl/acpi.c | 10 | ||||
| -rw-r--r-- | drivers/cxl/core/pmem.c | 4 | ||||
| -rw-r--r-- | drivers/cxl/core/port.c | 47 | ||||
| -rw-r--r-- | drivers/cxl/cxl.h | 81 | ||||
| -rw-r--r-- | drivers/cxl/pmem.c | 12 | ||||
| -rw-r--r-- | drivers/nvdimm/nd-core.h | 2 | ||||
| -rw-r--r-- | lib/Kconfig.debug | 23 |
7 files changed, 154 insertions, 25 deletions
diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c index 4e8086525edc..93d1dc56892a 100644 --- a/drivers/cxl/acpi.c +++ b/drivers/cxl/acpi.c @@ -176,14 +176,14 @@ static struct cxl_dport *find_dport_by_dev(struct cxl_port *port, struct device { struct cxl_dport *dport; - device_lock(&port->dev); + cxl_device_lock(&port->dev); list_for_each_entry(dport, &port->dports, list) if (dport->dport == dev) { - device_unlock(&port->dev); + cxl_device_unlock(&port->dev); return dport; } - device_unlock(&port->dev); + cxl_device_unlock(&port->dev); return NULL; } @@ -264,9 +264,9 @@ static int add_host_bridge_uport(struct device *match, void *arg) if (IS_ERR(cxld)) return PTR_ERR(cxld); - device_lock(&port->dev); + cxl_device_lock(&port->dev); dport = list_first_entry(&port->dports, typeof(*dport), list); - device_unlock(&port->dev); + cxl_device_unlock(&port->dev); single_port_map[0] = dport->port_id; diff --git a/drivers/cxl/core/pmem.c b/drivers/cxl/core/pmem.c index b5fca97b0a07..40b3f5030496 100644 --- a/drivers/cxl/core/pmem.c +++ b/drivers/cxl/core/pmem.c @@ -115,10 +115,10 @@ static void unregister_nvb(void *_cxl_nvb) * work to flush. Once the state has been changed to 'dead' then no new * work can be queued by user-triggered bind. */ - device_lock(&cxl_nvb->dev); + cxl_device_lock(&cxl_nvb->dev); flush = cxl_nvb->state != CXL_NVB_NEW; cxl_nvb->state = CXL_NVB_DEAD; - device_unlock(&cxl_nvb->dev); + cxl_device_unlock(&cxl_nvb->dev); /* * Even though the device core will trigger device_release_driver() diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c index f287d87da6d6..9285cdb734b2 100644 --- a/drivers/cxl/core/port.c +++ b/drivers/cxl/core/port.c @@ -111,7 +111,7 @@ static ssize_t target_list_show(struct device *dev, ssize_t offset = 0; int i, rc = 0; - device_lock(dev); + cxl_device_lock(dev); for (i = 0; i < cxld->interleave_ways; i++) { struct cxl_dport *dport = cxld->target[i]; struct cxl_dport *next = NULL; @@ -127,7 +127,7 @@ static ssize_t target_list_show(struct device *dev, break; offset += rc; } - device_unlock(dev); + cxl_device_unlock(dev); if (rc < 0) return rc; @@ -214,6 +214,12 @@ bool is_root_decoder(struct device *dev) } EXPORT_SYMBOL_NS_GPL(is_root_decoder, CXL); +bool is_cxl_decoder(struct device *dev) +{ + return dev->type->release == cxl_decoder_release; +} +EXPORT_SYMBOL_NS_GPL(is_cxl_decoder, CXL); + struct cxl_decoder *to_cxl_decoder(struct device *dev) { if (dev_WARN_ONCE(dev, dev->type->release != cxl_decoder_release, @@ -235,10 +241,10 @@ static void cxl_port_release(struct device *dev) struct cxl_port *port = to_cxl_port(dev); struct cxl_dport *dport, *_d; - device_lock(dev); + cxl_device_lock(dev); list_for_each_entry_safe(dport, _d, &port->dports, list) cxl_dport_release(dport); - device_unlock(dev); + cxl_device_unlock(dev); ida_free(&cxl_port_ida, port->id); kfree(port); } @@ -254,6 +260,12 @@ static const struct device_type cxl_port_type = { .groups = cxl_port_attribute_groups, }; +bool is_cxl_port(struct device *dev) +{ + return dev->type == &cxl_port_type; +} +EXPORT_SYMBOL_NS_GPL(is_cxl_port, CXL); + struct cxl_port *to_cxl_port(struct device *dev) { if (dev_WARN_ONCE(dev, dev->type != &cxl_port_type, @@ -261,13 +273,14 @@ struct cxl_port *to_cxl_port(struct device *dev) return NULL; return container_of(dev, struct cxl_port, dev); } +EXPORT_SYMBOL_NS_GPL(to_cxl_port, CXL); static void unregister_port(void *_port) { struct cxl_port *port = _port; struct cxl_dport *dport; - device_lock(&port->dev); + cxl_device_lock(&port->dev); list_for_each_entry(dport, &port->dports, list) { char link_name[CXL_TARGET_STRLEN]; @@ -276,7 +289,7 @@ static void unregister_port(void *_port) continue; sysfs_remove_link(&port->dev.kobj, link_name); } - device_unlock(&port->dev); + cxl_device_unlock(&port->dev); device_unregister(&port->dev); } @@ -407,7 +420,7 @@ static int add_dport(struct cxl_port *port, struct cxl_dport *new) { struct cxl_dport *dup; - device_lock(&port->dev); + cxl_device_lock(&port->dev); dup = find_dport(port, new->port_id); if (dup) dev_err(&port->dev, @@ -416,7 +429,7 @@ static int add_dport(struct cxl_port *port, struct cxl_dport *new) dev_name(dup->dport)); else list_add_tail(&new->list, &port->dports); - device_unlock(&port->dev); + cxl_device_unlock(&port->dev); return dup ? -EEXIST : 0; } @@ -475,7 +488,7 @@ static int decoder_populate_targets(struct cxl_decoder *cxld, if (!target_map) return 0; - device_lock(&port->dev); + cxl_device_lock(&port->dev); if (list_empty(&port->dports)) { rc = -EINVAL; goto out_unlock; @@ -492,7 +505,7 @@ static int decoder_populate_targets(struct cxl_decoder *cxld, } out_unlock: - device_unlock(&port->dev); + cxl_device_unlock(&port->dev); return rc; } @@ -717,15 +730,27 @@ static int cxl_bus_match(struct device *dev, struct device_driver *drv) static int cxl_bus_probe(struct device *dev) { - return to_cxl_drv(dev->driver)->probe(dev); + int rc; + + /* + * Take the CXL nested lock since the driver core only holds + * @dev->mutex and not @dev->lockdep_mutex. + */ + cxl_nested_lock(dev); + rc = to_cxl_drv(dev->driver)->probe(dev); + cxl_nested_unlock(dev); + + return rc; } static void cxl_bus_remove(struct device *dev) { struct cxl_driver *cxl_drv = to_cxl_drv(dev->driver); + cxl_nested_lock(dev); if (cxl_drv->remove) cxl_drv->remove(dev); + cxl_nested_unlock(dev); } struct bus_type cxl_bus_type = { diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h index 7ade555076bc..6a38d2e1f3dd 100644 --- a/drivers/cxl/cxl.h +++ b/drivers/cxl/cxl.h @@ -291,6 +291,7 @@ static inline bool is_cxl_root(struct cxl_port *port) return port->uport == port->dev.parent; } +bool is_cxl_port(struct device *dev); struct cxl_port *to_cxl_port(struct device *dev); struct cxl_port *devm_cxl_add_port(struct device *host, struct device *uport, resource_size_t component_reg_phys, @@ -301,6 +302,7 @@ int cxl_add_dport(struct cxl_port *port, struct device *dport, int port_id, struct cxl_decoder *to_cxl_decoder(struct device *dev); bool is_root_decoder(struct device *dev); +bool is_cxl_decoder(struct device *dev); struct cxl_decoder *cxl_root_decoder_alloc(struct cxl_port *port, unsigned int nr_targets); struct cxl_decoder *cxl_switch_decoder_alloc(struct cxl_port *port, @@ -353,4 +355,83 @@ struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_nvdimm *cxl_nvd); #ifndef __mock #define __mock static #endif + +#ifdef CONFIG_PROVE_CXL_LOCKING +enum cxl_lock_class { + CXL_ANON_LOCK, + CXL_NVDIMM_LOCK, + CXL_NVDIMM_BRIDGE_LOCK, + CXL_PORT_LOCK, + /* + * Be careful to add new lock classes here, CXL_PORT_LOCK is + * extended by the port depth, so a maximum CXL port topology + * depth would need to be defined first. + */ +}; + +static inline void cxl_nested_lock(struct device *dev) +{ + if (is_cxl_port(dev)) { + struct cxl_port *port = to_cxl_port(dev); + + mutex_lock_nested(&dev->lockdep_mutex, + CXL_PORT_LOCK + port->depth); + } else if (is_cxl_decoder(dev)) { + struct cxl_port *port = to_cxl_port(dev->parent); + + /* + * A decoder is the immediate child of a port, so set + * its lock class equal to other child device siblings. + */ + mutex_lock_nested(&dev->lockdep_mutex, + CXL_PORT_LOCK + port->depth + 1); + } else if (is_cxl_nvdimm_bridge(dev)) + mutex_lock_nested(&dev->lockdep_mutex, CXL_NVDIMM_BRIDGE_LOCK); + else if (is_cxl_nvdimm(dev)) + mutex_lock_nested(&dev->lockdep_mutex, CXL_NVDIMM_LOCK); + else + mutex_lock_nested(&dev->lockdep_mutex, CXL_ANON_LOCK); +} + +static inline void cxl_nested_unlock(struct device *dev) +{ + mutex_unlock(&dev->lockdep_mutex); +} + +static inline void cxl_device_lock(struct device *dev) +{ + /* + * For double lock errors the lockup will happen before lockdep + * warns at cxl_nested_lock(), so assert explicitly. + */ + lockdep_assert_not_held(&dev->lockdep_mutex); + + device_lock(dev); + cxl_nested_lock(dev); +} + +static inline void cxl_device_unlock(struct device *dev) +{ + cxl_nested_unlock(dev); + device_unlock(dev); +} +#else +static inline void cxl_nested_lock(struct device *dev) +{ +} + +static inline void cxl_nested_unlock(struct device *dev) +{ +} + +static inline void cxl_device_lock(struct device *dev) +{ + device_lock(dev); +} + +static inline void cxl_device_unlock(struct device *dev) +{ + device_unlock(dev); +} +#endif #endif /* __CXL_H__ */ diff --git a/drivers/cxl/pmem.c b/drivers/cxl/pmem.c index b65a272a2d6d..15ad666ab03e 100644 --- a/drivers/cxl/pmem.c +++ b/drivers/cxl/pmem.c @@ -43,7 +43,7 @@ static int cxl_nvdimm_probe(struct device *dev) if (!cxl_nvb) return -ENXIO; - device_lock(&cxl_nvb->dev); + cxl_device_lock(&cxl_nvb->dev); if (!cxl_nvb->nvdimm_bus) { rc = -ENXIO; goto out; @@ -68,7 +68,7 @@ static int cxl_nvdimm_probe(struct device *dev) dev_set_drvdata(dev, nvdimm); rc = devm_add_action_or_reset(dev, unregister_nvdimm, nvdimm); out: - device_unlock(&cxl_nvb->dev); + cxl_device_unlock(&cxl_nvb->dev); put_device(&cxl_nvb->dev); return rc; @@ -233,7 +233,7 @@ static void cxl_nvb_update_state(struct work_struct *work) struct nvdimm_bus *victim_bus = NULL; bool release = false, rescan = false; - device_lock(&cxl_nvb->dev); + cxl_device_lock(&cxl_nvb->dev); switch (cxl_nvb->state) { case CXL_NVB_ONLINE: if (!online_nvdimm_bus(cxl_nvb)) { @@ -251,7 +251,7 @@ static void cxl_nvb_update_state(struct work_struct *work) default: break; } - device_unlock(&cxl_nvb->dev); + cxl_device_unlock(&cxl_nvb->dev); if (release) device_release_driver(&cxl_nvb->dev); @@ -327,9 +327,9 @@ static int cxl_nvdimm_bridge_reset(struct device *dev, void *data) return 0; cxl_nvb = to_cxl_nvdimm_bridge(dev); - device_lock(dev); + cxl_device_lock(dev); cxl_nvb->state = CXL_NVB_NEW; - device_unlock(dev); + cxl_device_unlock(dev); return 0; } diff --git a/drivers/nvdimm/nd-core.h b/drivers/nvdimm/nd-core.h index a11850dd475d..2650a852eeaf 100644 --- a/drivers/nvdimm/nd-core.h +++ b/drivers/nvdimm/nd-core.h @@ -185,7 +185,7 @@ static inline void devm_nsio_disable(struct device *dev, } #endif -#ifdef CONFIG_PROVE_LOCKING +#ifdef CONFIG_PROVE_NVDIMM_LOCKING extern struct class *nd_class; enum { diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 14b89aa37c5c..7dea203964f7 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1516,6 +1516,29 @@ config CSD_LOCK_WAIT_DEBUG include the IPI handler function currently executing (if any) and relevant stack traces. +choice + prompt "Lock debugging: prove subsystem device_lock() correctness" + depends on PROVE_LOCKING + help + For subsystems that have instrumented their usage of the device_lock() + with nested annotations, enable lock dependency checking. The locking + hierarchy 'subclass' identifiers are not compatible across + sub-systems, so only one can be enabled at a time. + +config PROVE_NVDIMM_LOCKING + bool "NVDIMM" + depends on LIBNVDIMM + help + Enable lockdep to validate nd_device_lock() usage. + +config PROVE_CXL_LOCKING + bool "CXL" + depends on CXL_BUS + help + Enable lockdep to validate cxl_device_lock() usage. + +endchoice + endmenu # lock debugging config TRACE_IRQFLAGS |