On Thu, Apr 21, 2022 at 08:33:29AM -0700, Dan Williams wrote:
> In response to an attempt to expand dev->lockdep_mutex for device_lock()
> validation [1], Peter points out [2] that the lockdep API already has
> the ability to assign a dedicated lock class per subsystem device-type.
>
> Use lockdep_set_class() to override the default device_lock()
> '__lockdep_no_validate__' class for each NVDIMM subsystem device-type. This
> enables lockdep to detect deadlocks and recursive locking within the
> device-driver core and the subsystem.
>
> Link:
> https://lore.kernel.org/r/164982968798.684294.15817853329823976469.st...@dwillia2-desk3.amr.corp.intel.com
> [1]
> Link:
> https://lore.kernel.org/r/ylf0dewci8myl...@hirez.programming.kicks-ass.net [2]
> Suggested-by: Peter Zijlstra <pet...@infradead.org>
> Cc: Vishal Verma <vishal.l.ve...@intel.com>
> Cc: Dave Jiang <dave.ji...@intel.com>
> Cc: Ira Weiny <ira.we...@intel.com>
> Signed-off-by: Dan Williams <dan.j.willi...@intel.com>
Reviewed-by: Ira Weiny <ira.we...@intel.com>
> ---
> drivers/nvdimm/btt_devs.c | 7 +++++--
> drivers/nvdimm/bus.c | 14 +++++++-------
> drivers/nvdimm/dax_devs.c | 4 ++--
> drivers/nvdimm/dimm_devs.c | 4 ++++
> drivers/nvdimm/namespace_devs.c | 10 +++++++++-
> drivers/nvdimm/nd-core.h | 2 +-
> drivers/nvdimm/pfn_devs.c | 7 +++++--
> drivers/nvdimm/region_devs.c | 4 ++++
> 8 files changed, 37 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/nvdimm/btt_devs.c b/drivers/nvdimm/btt_devs.c
> index e5a58520d398..120821796668 100644
> --- a/drivers/nvdimm/btt_devs.c
> +++ b/drivers/nvdimm/btt_devs.c
> @@ -178,6 +178,8 @@ bool is_nd_btt(struct device *dev)
> }
> EXPORT_SYMBOL(is_nd_btt);
>
> +static struct lock_class_key nvdimm_btt_key;
> +
> static struct device *__nd_btt_create(struct nd_region *nd_region,
> unsigned long lbasize, uuid_t *uuid,
> struct nd_namespace_common *ndns)
> @@ -205,6 +207,7 @@ static struct device *__nd_btt_create(struct nd_region
> *nd_region,
> dev->parent = &nd_region->dev;
> dev->type = &nd_btt_device_type;
> device_initialize(&nd_btt->dev);
> + lockdep_set_class(&nd_btt->dev.mutex, &nvdimm_btt_key);
> if (ndns && !__nd_attach_ndns(&nd_btt->dev, ndns, &nd_btt->ndns)) {
> dev_dbg(&ndns->dev, "failed, already claimed by %s\n",
> dev_name(ndns->claim));
> @@ -225,7 +228,7 @@ struct device *nd_btt_create(struct nd_region *nd_region)
> {
> struct device *dev = __nd_btt_create(nd_region, 0, NULL, NULL);
>
> - __nd_device_register(dev);
> + nd_device_register(dev);
> return dev;
> }
>
> @@ -324,7 +327,7 @@ static int __nd_btt_probe(struct nd_btt *nd_btt,
> if (!nd_btt->uuid)
> return -ENOMEM;
>
> - __nd_device_register(&nd_btt->dev);
> + nd_device_register(&nd_btt->dev);
>
> return 0;
> }
> diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c
> index 7b0d1443217a..85ffa04e93c2 100644
> --- a/drivers/nvdimm/bus.c
> +++ b/drivers/nvdimm/bus.c
> @@ -334,6 +334,8 @@ struct nvdimm_bus *nvdimm_to_bus(struct nvdimm *nvdimm)
> }
> EXPORT_SYMBOL_GPL(nvdimm_to_bus);
>
> +static struct lock_class_key nvdimm_bus_key;
> +
> struct nvdimm_bus *nvdimm_bus_register(struct device *parent,
> struct nvdimm_bus_descriptor *nd_desc)
> {
> @@ -360,6 +362,7 @@ struct nvdimm_bus *nvdimm_bus_register(struct device
> *parent,
> nvdimm_bus->dev.bus = &nvdimm_bus_type;
> nvdimm_bus->dev.of_node = nd_desc->of_node;
> device_initialize(&nvdimm_bus->dev);
> + lockdep_set_class(&nvdimm_bus->dev.mutex, &nvdimm_bus_key);
> device_set_pm_not_required(&nvdimm_bus->dev);
> rc = dev_set_name(&nvdimm_bus->dev, "ndbus%d", nvdimm_bus->id);
> if (rc)
> @@ -511,7 +514,7 @@ static void nd_async_device_unregister(void *d,
> async_cookie_t cookie)
> put_device(dev);
> }
>
> -void __nd_device_register(struct device *dev)
> +void nd_device_register(struct device *dev)
> {
> if (!dev)
> return;
> @@ -537,12 +540,6 @@ void __nd_device_register(struct device *dev)
> async_schedule_dev_domain(nd_async_device_register, dev,
> &nd_async_domain);
> }
> -
> -void nd_device_register(struct device *dev)
> -{
> - device_initialize(dev);
> - __nd_device_register(dev);
> -}
> EXPORT_SYMBOL(nd_device_register);
>
> void nd_device_unregister(struct device *dev, enum nd_async_mode mode)
> @@ -724,6 +721,8 @@ static void ndctl_release(struct device *dev)
> kfree(dev);
> }
>
> +static struct lock_class_key nvdimm_ndctl_key;
> +
> int nvdimm_bus_create_ndctl(struct nvdimm_bus *nvdimm_bus)
> {
> dev_t devt = MKDEV(nvdimm_bus_major, nvdimm_bus->id);
> @@ -734,6 +733,7 @@ int nvdimm_bus_create_ndctl(struct nvdimm_bus *nvdimm_bus)
> if (!dev)
> return -ENOMEM;
> device_initialize(dev);
> + lockdep_set_class(&dev->mutex, &nvdimm_ndctl_key);
> device_set_pm_not_required(dev);
> dev->class = nd_class;
> dev->parent = &nvdimm_bus->dev;
> diff --git a/drivers/nvdimm/dax_devs.c b/drivers/nvdimm/dax_devs.c
> index 99965077bac4..7f4a9d28b670 100644
> --- a/drivers/nvdimm/dax_devs.c
> +++ b/drivers/nvdimm/dax_devs.c
> @@ -80,7 +80,7 @@ struct device *nd_dax_create(struct nd_region *nd_region)
> nd_dax = nd_dax_alloc(nd_region);
> if (nd_dax)
> dev = nd_pfn_devinit(&nd_dax->nd_pfn, NULL);
> - __nd_device_register(dev);
> + nd_device_register(dev);
> return dev;
> }
>
> @@ -119,7 +119,7 @@ int nd_dax_probe(struct device *dev, struct
> nd_namespace_common *ndns)
> nd_detach_ndns(dax_dev, &nd_pfn->ndns);
> put_device(dax_dev);
> } else
> - __nd_device_register(dax_dev);
> + nd_device_register(dax_dev);
>
> return rc;
> }
> diff --git a/drivers/nvdimm/dimm_devs.c b/drivers/nvdimm/dimm_devs.c
> index ee507eed42b5..27b8f8cd1b48 100644
> --- a/drivers/nvdimm/dimm_devs.c
> +++ b/drivers/nvdimm/dimm_devs.c
> @@ -570,6 +570,8 @@ bool is_nvdimm(struct device *dev)
> return dev->type == &nvdimm_device_type;
> }
>
> +static struct lock_class_key nvdimm_key;
> +
> struct nvdimm *__nvdimm_create(struct nvdimm_bus *nvdimm_bus,
> void *provider_data, const struct attribute_group **groups,
> unsigned long flags, unsigned long cmd_mask, int num_flush,
> @@ -613,6 +615,8 @@ struct nvdimm *__nvdimm_create(struct nvdimm_bus
> *nvdimm_bus,
> /* get security state and extended (master) state */
> nvdimm->sec.flags = nvdimm_security_flags(nvdimm, NVDIMM_USER);
> nvdimm->sec.ext_flags = nvdimm_security_flags(nvdimm, NVDIMM_MASTER);
> + device_initialize(dev);
> + lockdep_set_class(&dev->mutex, &nvdimm_key);
> nd_device_register(dev);
>
> return nvdimm;
> diff --git a/drivers/nvdimm/namespace_devs.c b/drivers/nvdimm/namespace_devs.c
> index 62b83b2e26e3..5197a813849d 100644
> --- a/drivers/nvdimm/namespace_devs.c
> +++ b/drivers/nvdimm/namespace_devs.c
> @@ -1830,6 +1830,8 @@ static struct device *nd_namespace_pmem_create(struct
> nd_region *nd_region)
> return dev;
> }
>
> +static struct lock_class_key nvdimm_namespace_key;
> +
> void nd_region_create_ns_seed(struct nd_region *nd_region)
> {
> WARN_ON(!is_nvdimm_bus_locked(&nd_region->dev));
> @@ -1845,8 +1847,12 @@ void nd_region_create_ns_seed(struct nd_region
> *nd_region)
> */
> if (!nd_region->ns_seed)
> dev_err(&nd_region->dev, "failed to create namespace\n");
> - else
> + else {
> + device_initialize(nd_region->ns_seed);
> + lockdep_set_class(&nd_region->ns_seed->mutex,
> + &nvdimm_namespace_key);
> nd_device_register(nd_region->ns_seed);
> + }
> }
>
> void nd_region_create_dax_seed(struct nd_region *nd_region)
> @@ -2200,6 +2206,8 @@ int nd_region_register_namespaces(struct nd_region
> *nd_region, int *err)
> if (id < 0)
> break;
> dev_set_name(dev, "namespace%d.%d", nd_region->id, id);
> + device_initialize(dev);
> + lockdep_set_class(&dev->mutex, &nvdimm_namespace_key);
> nd_device_register(dev);
> }
> if (i)
> diff --git a/drivers/nvdimm/nd-core.h b/drivers/nvdimm/nd-core.h
> index 448f9dcb4bb7..99b04106434b 100644
> --- a/drivers/nvdimm/nd-core.h
> +++ b/drivers/nvdimm/nd-core.h
> @@ -106,7 +106,7 @@ void nd_region_create_dax_seed(struct nd_region
> *nd_region);
> int nvdimm_bus_create_ndctl(struct nvdimm_bus *nvdimm_bus);
> void nvdimm_bus_destroy_ndctl(struct nvdimm_bus *nvdimm_bus);
> void nd_synchronize(void);
> -void __nd_device_register(struct device *dev);
> +void nd_device_register(struct device *dev);
> struct nd_label_id;
> char *nd_label_gen_id(struct nd_label_id *label_id, const uuid_t *uuid,
> u32 flags);
> diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c
> index c31e184bfa45..0cd396d0024c 100644
> --- a/drivers/nvdimm/pfn_devs.c
> +++ b/drivers/nvdimm/pfn_devs.c
> @@ -291,6 +291,8 @@ bool is_nd_pfn(struct device *dev)
> }
> EXPORT_SYMBOL(is_nd_pfn);
>
> +static struct lock_class_key nvdimm_pfn_key;
> +
> struct device *nd_pfn_devinit(struct nd_pfn *nd_pfn,
> struct nd_namespace_common *ndns)
> {
> @@ -303,6 +305,7 @@ struct device *nd_pfn_devinit(struct nd_pfn *nd_pfn,
> nd_pfn->align = nd_pfn_default_alignment();
> dev = &nd_pfn->dev;
> device_initialize(&nd_pfn->dev);
> + lockdep_set_class(&nd_pfn->dev.mutex, &nvdimm_pfn_key);
> if (ndns && !__nd_attach_ndns(&nd_pfn->dev, ndns, &nd_pfn->ndns)) {
> dev_dbg(&ndns->dev, "failed, already claimed by %s\n",
> dev_name(ndns->claim));
> @@ -346,7 +349,7 @@ struct device *nd_pfn_create(struct nd_region *nd_region)
> nd_pfn = nd_pfn_alloc(nd_region);
> dev = nd_pfn_devinit(nd_pfn, NULL);
>
> - __nd_device_register(dev);
> + nd_device_register(dev);
> return dev;
> }
>
> @@ -643,7 +646,7 @@ int nd_pfn_probe(struct device *dev, struct
> nd_namespace_common *ndns)
> nd_detach_ndns(pfn_dev, &nd_pfn->ndns);
> put_device(pfn_dev);
> } else
> - __nd_device_register(pfn_dev);
> + nd_device_register(pfn_dev);
>
> return rc;
> }
> diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c
> index 0cb274c2b508..8650e8d39c89 100644
> --- a/drivers/nvdimm/region_devs.c
> +++ b/drivers/nvdimm/region_devs.c
> @@ -949,6 +949,8 @@ static unsigned long default_align(struct nd_region
> *nd_region)
> return align;
> }
>
> +static struct lock_class_key nvdimm_region_key;
> +
> static struct nd_region *nd_region_create(struct nvdimm_bus *nvdimm_bus,
> struct nd_region_desc *ndr_desc,
> const struct device_type *dev_type, const char *caller)
> @@ -1035,6 +1037,8 @@ static struct nd_region *nd_region_create(struct
> nvdimm_bus *nvdimm_bus,
> else
> nd_region->flush = NULL;
>
> + device_initialize(dev);
> + lockdep_set_class(&dev->mutex, &nvdimm_region_key);
> nd_device_register(dev);
>
> return nd_region;
>
