lib/test_rhashtable: Make test_insert_dup() allocate its hash table dynamically

The test_insert_dup() function from lib/test_rhashtable.c passes a
pointer to a stack object to rhltable_init(). Allocate the hash table
dynamically to avoid that the following is reported with object
debugging enabled:

ODEBUG: object (ptrval) is on stack (ptrval), but NOT annotated.
WARNING: CPU: 0 PID: 1 at lib/debugobjects.c:368 __debug_object_init+0x312/0x480
Modules linked in:
EIP: __debug_object_init+0x312/0x480
Call Trace:
? debug_object_init+0x1a/0x20
? __init_work+0x16/0x30
? rhashtable_init+0x1e1/0x460
? sched_clock_cpu+0x57/0xe0
? rhltable_init+0xb/0x20
? test_insert_dup+0x32/0x20f
? trace_hardirqs_on+0x38/0xf0
? ida_dump+0x10/0x10
? jhash+0x130/0x130
? my_hashfn+0x30/0x30
? test_rht_init+0x6aa/0xab4
? ida_dump+0x10/0x10
? test_rhltable+0xc5c/0xc5c
? do_one_initcall+0x67/0x28e
? trace_hardirqs_off+0x22/0xe0
? restore_all_kernel+0xf/0x70
? trace_hardirqs_on_thunk+0xc/0x10
? restore_all_kernel+0xf/0x70
? kernel_init_freeable+0x142/0x213
? rest_init+0x230/0x230
? kernel_init+0x10/0x110
? schedule_tail_wrapper+0x9/0xc
? ret_from_fork+0x19/0x24

Cc: Thomas Graf <[e-mail]>
Cc: Herbert Xu <[e-mail]>
Cc: [e-mail]
Cc: [e-mail]
Signed-off-by: Bart Van Assche <[e-mail]>
Acked-by: Herbert Xu <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

lib/test_rhashtable.c

···
 static int __init test_insert_dup(struct test_obj_rhl *rhl_test_objects,
 				  int cnt, bool slow)
 {
-	struct rhltable rhlt;
+	struct rhltable *rhlt;
 	unsigned int i, ret;
 	const char *key;
 	int err = 0;
 
-	err = rhltable_init(&rhlt, &test_rht_params_dup);
-	if (WARN_ON(err))
+	rhlt = kmalloc(sizeof(*rhlt), GFP_KERNEL);
+	if (WARN_ON(!rhlt))
+		return -EINVAL;
+
+	err = rhltable_init(rhlt, &test_rht_params_dup);
+	if (WARN_ON(err)) {
+		kfree(rhlt);
 		return err;
+	}
 
 	for (i = 0; i < cnt; i++) {
 		rhl_test_objects[i].value.tid = i;
-		key = rht_obj(&rhlt.ht, &rhl_test_objects[i].list_node.rhead);
+		key = rht_obj(&rhlt->ht, &rhl_test_objects[i].list_node.rhead);
 		key += test_rht_params_dup.key_offset;
 
 		if (slow) {
-			err = PTR_ERR(rhashtable_insert_slow(&rhlt.ht, key,
+			err = PTR_ERR(rhashtable_insert_slow(&rhlt->ht, key,
 							     &rhl_test_objects[i].list_node.rhead));
 			if (err == -EAGAIN)
 				err = 0;
 		} else
-			err = rhltable_insert(&rhlt,
+			err = rhltable_insert(rhlt,
 					      &rhl_test_objects[i].list_node,
 					      test_rht_params_dup);
 		if (WARN(err, "error %d on element %d/%d (%s)\n", err, i, cnt, slow? "slow" : "fast"))
 			goto skip_print;
 	}
 
-	ret = print_ht(&rhlt);
+	ret = print_ht(rhlt);
 	WARN(ret != cnt, "missing rhltable elements (%d != %d, %s)\n", ret, cnt, slow? "slow" : "fast");
 
 skip_print:
-	rhltable_destroy(&rhlt);
+	rhltable_destroy(rhlt);
+	kfree(rhlt);
 
 	return 0;
 }