diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 5cc3506574e9..116a35051be6 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -358,6 +358,16 @@ config DEBUG_KMEMLEAK In order to access the kmemleak file, debugfs needs to be mounted (usually at /sys/kernel/debug). +config DEBUG_KMEMLEAK_TEST + tristate "Simple test for the kernel memory leak detector" + depends on DEBUG_KMEMLEAK + help + Say Y or M here to build a test for the kernel memory leak + detector. This option enables a module that explicitly leaks + memory. + + If unsure, say N. + config DEBUG_PREEMPT bool "Debug preemptible kernel" depends on DEBUG_KERNEL && PREEMPT && (TRACE_IRQFLAGS_SUPPORT || PPC64) diff --git a/mm/Makefile b/mm/Makefile index cb84a025fdbf..e89acb090b4d 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -39,3 +39,4 @@ endif obj-$(CONFIG_QUICKLIST) += quicklist.o obj-$(CONFIG_CGROUP_MEM_RES_CTLR) += memcontrol.o page_cgroup.o obj-$(CONFIG_DEBUG_KMEMLEAK) += kmemleak.o +obj-$(CONFIG_DEBUG_KMEMLEAK_TEST) += kmemleak-test.o diff --git a/mm/kmemleak-test.c b/mm/kmemleak-test.c new file mode 100644 index 000000000000..d5292fc6f523 --- /dev/null +++ b/mm/kmemleak-test.c @@ -0,0 +1,111 @@ +/* + * mm/kmemleak-test.c + * + * Copyright (C) 2008 ARM Limited + * Written by Catalin Marinas + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +struct test_node { + long header[25]; + struct list_head list; + long footer[25]; +}; + +static LIST_HEAD(test_list); +static DEFINE_PER_CPU(void *, test_pointer); + +/* + * Some very simple testing. This function needs to be extended for + * proper testing. + */ +static int __init kmemleak_test_init(void) +{ + struct test_node *elem; + int i; + + printk(KERN_INFO "Kmemleak testing\n"); + + /* make some orphan objects */ + pr_info("kmemleak: kmalloc(32) = %p\n", kmalloc(32, GFP_KERNEL)); + pr_info("kmemleak: kmalloc(32) = %p\n", kmalloc(32, GFP_KERNEL)); + pr_info("kmemleak: kmalloc(1024) = %p\n", kmalloc(1024, GFP_KERNEL)); + pr_info("kmemleak: kmalloc(1024) = %p\n", kmalloc(1024, GFP_KERNEL)); + pr_info("kmemleak: kmalloc(2048) = %p\n", kmalloc(2048, GFP_KERNEL)); + pr_info("kmemleak: kmalloc(2048) = %p\n", kmalloc(2048, GFP_KERNEL)); + pr_info("kmemleak: kmalloc(4096) = %p\n", kmalloc(4096, GFP_KERNEL)); + pr_info("kmemleak: kmalloc(4096) = %p\n", kmalloc(4096, GFP_KERNEL)); +#ifndef CONFIG_MODULES + pr_info("kmemleak: kmem_cache_alloc(files_cachep) = %p\n", + kmem_cache_alloc(files_cachep, GFP_KERNEL)); + pr_info("kmemleak: kmem_cache_alloc(files_cachep) = %p\n", + kmem_cache_alloc(files_cachep, GFP_KERNEL)); +#endif + pr_info("kmemleak: vmalloc(64) = %p\n", vmalloc(64)); + pr_info("kmemleak: vmalloc(64) = %p\n", vmalloc(64)); + pr_info("kmemleak: vmalloc(64) = %p\n", vmalloc(64)); + pr_info("kmemleak: vmalloc(64) = %p\n", vmalloc(64)); + pr_info("kmemleak: vmalloc(64) = %p\n", vmalloc(64)); + + /* + * Add elements to a list. They should only appear as orphan + * after the module is removed. + */ + for (i = 0; i < 10; i++) { + elem = kmalloc(sizeof(*elem), GFP_KERNEL); + pr_info("kmemleak: kmalloc(sizeof(*elem)) = %p\n", elem); + if (!elem) + return -ENOMEM; + memset(elem, 0, sizeof(*elem)); + INIT_LIST_HEAD(&elem->list); + + list_add_tail(&elem->list, &test_list); + } + + for_each_possible_cpu(i) { + per_cpu(test_pointer, i) = kmalloc(129, GFP_KERNEL); + pr_info("kmemleak: kmalloc(129) = %p\n", + per_cpu(test_pointer, i)); + } + + return 0; +} +module_init(kmemleak_test_init); + +static void __exit kmemleak_test_exit(void) +{ + struct test_node *elem, *tmp; + + /* + * Remove the list elements without actually freeing the + * memory. + */ + list_for_each_entry_safe(elem, tmp, &test_list, list) + list_del(&elem->list); +} +module_exit(kmemleak_test_exit); + +MODULE_LICENSE("GPL");