remoteproc: Use a local copy for the name field

The current name field used in the remoteproc structure is simply
a pointer to a name field supplied during the rproc_alloc() call.
The pointer passed in by remoteproc drivers during registration is
typically a dev_name pointer, but it is possible that the pointer
will no longer remain valid if the devices themselves were created
at runtime like in the case of of_platform_populate(), and were
deleted upon any failures within the respective remoteproc driver
probe function.

So, allocate and maintain a local copy for this name field to
keep it agnostic of the logic used in the remoteproc drivers.
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Suman Anna <s-anna@ti.com>
Link: https://lore.kernel.org/r/20200417002036.24359-3-s-anna@ti.comSigned-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

drivers/remoteproc/remoteproc_core.c

@@ -1997,6 +1997,7 @@ static void rproc_type_release(struct device *dev)
 		ida_simple_remove(&rproc_dev_index, rproc->index);
 
 	kfree_const(rproc->firmware);
+	kfree_const(rproc->name);
 	kfree(rproc->ops);
 	kfree(rproc);
 }
@@ -2084,7 +2085,6 @@ struct rproc *rproc_alloc(struct device *dev, const char *name,
 	if (!rproc)
 		return NULL;
 
-	rproc->name = name;
 	rproc->priv = &rproc[1];
 	rproc->auto_boot = true;
 	rproc->elf_class = ELFCLASSNONE;
@@ -2097,6 +2097,10 @@ struct rproc *rproc_alloc(struct device *dev, const char *name,
 	rproc->dev.driver_data = rproc;
 	idr_init(&rproc->notifyids);
 
+	rproc->name = kstrdup_const(name, GFP_KERNEL);
+	if (!rproc->name)
+		goto put_device;
+
 	if (rproc_alloc_firmware(rproc, name, firmware))
 		goto put_device;