Re: WARNING: at kernel/workqueue.c:1473 __queue_work+0x3b8/0x3d0

From: Daniel Jordan
Date: Mon Mar 02 2020 - 12:26:06 EST


On Sun, Mar 01, 2020 at 06:53:51PM +0100, Corentin Labbe wrote:
> I tried to bisect this problem, but the result is:
...
> # first bad commit: [81ff5d2cba4f86cd850b9ee4a530cd221ee45aa3] Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
>
> The only interesting thing I see in this MR is: "Add fuzz testing to testmgr"
>
> But this wont help.

Hm, that merge commit has only a couple lines of powerpc build change, so maybe
there's something nondeterministic going on.

Does this fix it? I can't verify but figure it's worth trying the simplest
explanation first, which is that the work isn't initialized by the time it's
queued.

thanks,
daniel

---8<---

Subject: [PATCH] module: statically initialize init section freeing data

Signed-off-by: Daniel Jordan <daniel.m.jordan@xxxxxxxxxx>
---
kernel/module.c | 13 +++----------
1 file changed, 3 insertions(+), 10 deletions(-)

diff --git a/kernel/module.c b/kernel/module.c
index 33569a01d6e1..db0cda206167 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -88,8 +88,9 @@ 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

@@ -3501,14 +3502,6 @@ 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.
*
--
2.25.1