Re: BUG: MAX_STACK_TRACE_ENTRIES too low!

From: Linus Torvalds
Date: Mon Mar 11 2019 - 13:48:31 EST


On Mon, Mar 11, 2019 at 8:19 AM Bart Van Assche <bvanassche@xxxxxxx> wrote:
>
> I think this issue has been fixed by a commit that went upstream yesterday. Hence:
>
> #syz fix: workqueue, lockdep: Fix an alloc_workqueue() error path

Well, syzbot just reported a problem with that fix itself ("WARNING in
lockdep_unregister_key").

Looks like now the lockdep_unregister_key() cleanup might be called
even when the lockdep map was never initialized at all in that error
case. Hmm?

I _think_ you need to split that "err_free_wq" label into "just free
the wq" and "unregister lockdep and free wq".

But I didn't look any more closely, I might be misreading things.

Linus