From fdf09ab887829cd1b671e45d9549f8ec1ffda0fa Mon Sep 17 00:00:00 2001 From: Daniel Jordan Date: Thu, 8 Oct 2020 13:32:20 -0400 Subject: [PATCH] module: statically initialize init section freeing data Corentin hit the following workqueue warning when running with CRYPTO_MANAGER_EXTRA_TESTS: WARNING: CPU: 2 PID: 147 at kernel/workqueue.c:1473 __queue_work+0x3b8/0x3d0 Modules linked in: ghash_generic CPU: 2 PID: 147 Comm: modprobe Not tainted 5.6.0-rc1-next-20200214-00068-g166c9264f0b1-dirty #545 Hardware name: Pine H64 model A (DT) pc : __queue_work+0x3b8/0x3d0 Call trace: __queue_work+0x3b8/0x3d0 queue_work_on+0x6c/0x90 do_init_module+0x188/0x1f0 load_module+0x1d00/0x22b0 I wasn't able to reproduce on x86 or rpi 3b+. This is WARN_ON(!list_empty(&work->entry)) from __queue_work(), and it happens because the init_free_wq work item isn't initialized in time for a crypto test that requests the gcm module. Some crypto tests were recently moved earlier in boot as explained in commit c4741b230597 ("crypto: run initcalls for generic implementations earlier"), which went into mainline less than two weeks before the Fixes commit. Avoid the warning by statically initializing init_free_wq and the corresponding llist. Link: https://lore.kernel.org/lkml/20200217204803.GA13479@Red/ Fixes: 1a7b7d922081 ("modules: Use vmalloc special flag") Reported-by: Corentin Labbe Tested-by: Corentin Labbe Tested-on: sun50i-h6-pine-h64 Tested-on: imx8mn-ddr4-evk Tested-on: sun50i-a64-bananapi-m64 Reviewed-by: Eric Biggers Signed-off-by: Daniel Jordan Signed-off-by: Jessica Yu --- kernel/module.c | 13 +++---------- 1 file changed, 3 insertions(+), 10 deletions(-) diff --git a/kernel/module.c b/kernel/module.c index 2c00059ac1c9..7ff2dd301bd1 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -91,8 +91,9 @@ EXPORT_SYMBOL_GPL(module_mutex); static LIST_HEAD(modules); /* Work queue for freeing init sections in success case */ -static struct work_struct init_free_wq; -static struct llist_head init_free_list; +static void do_free_init(struct work_struct *w); +static DECLARE_WORK(init_free_wq, do_free_init); +static LLIST_HEAD(init_free_list); #ifdef CONFIG_MODULES_TREE_LOOKUP @@ -3582,14 +3583,6 @@ static void do_free_init(struct work_struct *w) } } -static int __init modules_wq_init(void) -{ - INIT_WORK(&init_free_wq, do_free_init); - init_llist_head(&init_free_list); - return 0; -} -module_init(modules_wq_init); - /* * This is where the real work happens. *