| 1 | // SPDX-License-Identifier: GPL-2.0+ |
|---|---|
| 2 | /* |
| 3 | * test_free_pages.c: Check that free_pages() doesn't leak memory |
| 4 | * Copyright (c) 2020 Oracle |
| 5 | * Author: Matthew Wilcox <willy@infradead.org> |
| 6 | */ |
| 7 | |
| 8 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| 9 | |
| 10 | #include <linux/gfp.h> |
| 11 | #include <linux/mm.h> |
| 12 | #include <linux/module.h> |
| 13 | |
| 14 | static void test_free_pages(gfp_t gfp) |
| 15 | { |
| 16 | unsigned int i; |
| 17 | |
| 18 | for (i = 0; i < 1000 * 1000; i++) { |
| 19 | unsigned long addr = __get_free_pages(gfp_mask: gfp, order: 3); |
| 20 | struct page *page = virt_to_page((void *)addr); |
| 21 | |
| 22 | /* Simulate page cache getting a speculative reference */ |
| 23 | get_page(page); |
| 24 | free_pages(addr, order: 3); |
| 25 | put_page(page); |
| 26 | } |
| 27 | } |
| 28 | |
| 29 | static int m_in(void) |
| 30 | { |
| 31 | pr_info("Testing with GFP_KERNEL\n"); |
| 32 | test_free_pages(GFP_KERNEL); |
| 33 | pr_info("Testing with GFP_KERNEL | __GFP_COMP\n"); |
| 34 | test_free_pages(GFP_KERNEL | __GFP_COMP); |
| 35 | pr_info("Test completed\n"); |
| 36 | |
| 37 | return 0; |
| 38 | } |
| 39 | |
| 40 | static void m_ex(void) |
| 41 | { |
| 42 | } |
| 43 | |
| 44 | module_init(m_in); |
| 45 | module_exit(m_ex); |
| 46 | MODULE_AUTHOR("Matthew Wilcox <willy@infradead.org>"); |
| 47 | MODULE_LICENSE("GPL"); |
| 48 |