3 files changed, 42 insertions, 3 deletions

diff --git a/drivers/cxl/core/pmem.c b/drivers/cxl/core/pmem.c
index 2e402f0b2a10..b5fca97b0a07 100644
--- a/drivers/cxl/core/pmem.c
+++ b/drivers/cxl/core/pmem.c
@@ -51,10 +51,16 @@ struct cxl_nvdimm_bridge *to_cxl_nvdimm_bridge(struct device *dev)
 }
 EXPORT_SYMBOL_NS_GPL(to_cxl_nvdimm_bridge, CXL);
 
-__mock int match_nvdimm_bridge(struct device *dev, const void *data)
+bool is_cxl_nvdimm_bridge(struct device *dev)
 {
 	return dev->type == &cxl_nvdimm_bridge_type;
 }
+EXPORT_SYMBOL_NS_GPL(is_cxl_nvdimm_bridge, CXL);
+
+__mock int match_nvdimm_bridge(struct device *dev, const void *data)
+{
+	return is_cxl_nvdimm_bridge(dev);
+}
 
 struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_nvdimm *cxl_nvd)
 {
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 3af704e9b448..ab4596f0b751 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -196,6 +196,13 @@ struct cxl_decoder {
 };
 
 
+/**
+ * enum cxl_nvdimm_brige_state - state machine for managing bus rescans
+ * @CXL_NVB_NEW: Set at bridge create and after cxl_pmem_wq is destroyed
+ * @CXL_NVB_DEAD: Set at brige unregistration to preclude async probing
+ * @CXL_NVB_ONLINE: Target state after successful ->probe()
+ * @CXL_NVB_OFFLINE: Target state after ->remove() or failed ->probe()
+ */
 enum cxl_nvdimm_brige_state {
 	CXL_NVB_NEW,
 	CXL_NVB_DEAD,
@@ -308,6 +315,7 @@ struct cxl_nvdimm_bridge *devm_cxl_add_nvdimm_bridge(struct device *host,
 						     struct cxl_port *port);
 struct cxl_nvdimm *to_cxl_nvdimm(struct device *dev);
 bool is_cxl_nvdimm(struct device *dev);
+bool is_cxl_nvdimm_bridge(struct device *dev);
 int devm_cxl_add_nvdimm(struct device *host, struct cxl_memdev *cxlmd);
 struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_nvdimm *cxl_nvd);
 
diff --git a/drivers/cxl/pmem.c b/drivers/cxl/pmem.c
index 17e82ae90456..b65a272a2d6d 100644
--- a/drivers/cxl/pmem.c
+++ b/drivers/cxl/pmem.c
@@ -315,6 +315,31 @@ static struct cxl_driver cxl_nvdimm_bridge_driver = {
 	.id = CXL_DEVICE_NVDIMM_BRIDGE,
 };
 
+/*
+ * Return all bridges to the CXL_NVB_NEW state to invalidate any
+ * ->state_work referring to the now destroyed cxl_pmem_wq.
+ */
+static int cxl_nvdimm_bridge_reset(struct device *dev, void *data)
+{
+	struct cxl_nvdimm_bridge *cxl_nvb;
+
+	if (!is_cxl_nvdimm_bridge(dev))
+		return 0;
+
+	cxl_nvb = to_cxl_nvdimm_bridge(dev);
+	device_lock(dev);
+	cxl_nvb->state = CXL_NVB_NEW;
+	device_unlock(dev);
+
+	return 0;
+}
+
+static void destroy_cxl_pmem_wq(void)
+{
+	destroy_workqueue(cxl_pmem_wq);
+	bus_for_each_dev(&cxl_bus_type, NULL, NULL, cxl_nvdimm_bridge_reset);
+}
+
 static __init int cxl_pmem_init(void)
 {
 	int rc;
@@ -340,7 +365,7 @@ static __init int cxl_pmem_init(void)
 err_nvdimm:
 	cxl_driver_unregister(&cxl_nvdimm_bridge_driver);
 err_bridge:
-	destroy_workqueue(cxl_pmem_wq);
+	destroy_cxl_pmem_wq();
 	return rc;
 }
 
@@ -348,7 +373,7 @@ static __exit void cxl_pmem_exit(void)
 {
 	cxl_driver_unregister(&cxl_nvdimm_driver);
 	cxl_driver_unregister(&cxl_nvdimm_bridge_driver);
-	destroy_workqueue(cxl_pmem_wq);
+	destroy_cxl_pmem_wq();
 }
 
 MODULE_LICENSE("GPL v2");