From a5bde5d8fde8a8cb28e59a672d5ddc5b9c1e7656 Mon Sep 17 00:00:00 2001 From: Breno Leitao Date: Wed, 5 Aug 2026 07:52:36 -0700 Subject: workqueue: skip the node_nr_active update for non-unbound workqueues apply_wqattrs_commit() updates node_nr_active->max unconditionally. wq->node_nr_active[] is only allocated for unbound workqueues, so guard the call before per-cpu workqueues start using this path. No functional change: only unbound workqueues reach apply_wqattrs_*() today. Signed-off-by: Breno Leitao Signed-off-by: Tejun Heo --- lib/test_free_pages.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) create mode 100644 lib/test_free_pages.c (limited to 'lib/test_free_pages.c') diff --git a/lib/test_free_pages.c b/lib/test_free_pages.c new file mode 100644 index 000000000..48952364c --- /dev/null +++ b/lib/test_free_pages.c @@ -0,0 +1,48 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * test_free_pages.c: Check that free_pages() doesn't leak memory + * Copyright (c) 2020 Oracle + * Author: Matthew Wilcox + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include + +static void test_free_pages(gfp_t gfp) +{ + unsigned int i; + + for (i = 0; i < 1000 * 1000; i++) { + unsigned long addr = __get_free_pages(gfp, 3); + struct page *page = virt_to_page((void *)addr); + + /* Simulate page cache getting a speculative reference */ + get_page(page); + free_pages(addr, 3); + put_page(page); + } +} + +static int m_in(void) +{ + pr_info("Testing with GFP_KERNEL\n"); + test_free_pages(GFP_KERNEL); + pr_info("Testing with GFP_KERNEL | __GFP_COMP\n"); + test_free_pages(GFP_KERNEL | __GFP_COMP); + pr_info("Test completed\n"); + + return 0; +} + +static void m_ex(void) +{ +} + +module_init(m_in); +module_exit(m_ex); +MODULE_AUTHOR("Matthew Wilcox "); +MODULE_DESCRIPTION("Check that free_pages() doesn't leak memory"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1