Date: Mon, 22 Nov 2010 08:59:34 -0800 From: Garrett Cooper <gcooper@FreeBSD.org> To: Dmitry Krivenok <krivenok.dmitry@gmail.com> Cc: freebsd-hackers@freebsd.org Subject: Re: printf doesn't work from kernel modules Message-ID: <AANLkTimQ323D_YAN1Z-1uKYWLCkFqyfRvvUp6rb0K_F4@mail.gmail.com> In-Reply-To: <AANLkTinbx0NpZfJoyv4vp3HMFcFUg9Uv9Ru_YdikW6Uv@mail.gmail.com> References: <AANLkTinbx0NpZfJoyv4vp3HMFcFUg9Uv9Ru_YdikW6Uv@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Mon, Nov 22, 2010 at 5:38 AM, Dmitry Krivenok
<krivenok.dmitry@gmail.com> wrote:
> Hello Hackers,
> Recently I installed 8.1 on my laptop and recompiled the kernel.
> The system works fine, but I have a strange problem with my own
> trivial kernel module.
> I noticed that printf function doesn't produce any output (according to
> dmesg) if I call it from a module. Note, that the same module works
> perfectly on another 8.1 and CURRENT systems. Moreover, I added
> debug message (printf ("Bla bla bla\n");) =A0in my kernel and found that
> it works fine (i.e. works if compiled directly in kernel, but doesn't wor=
k
> from module). Same effect with stock 8.1 kernel.
>
> I see the same problem with examples in /usr/share/examples/kld.
>
> I don't believe this is a real problem in FreeBSD. I'm sure this is some
> kind of configuration issue, but I cannot understand what exactly is wron=
g.
>
> What could cause such behaviour?
> Any ideas?
Which example did you try and run (it looks like the dyn_sysctl test
would be a good one to try)?
-Garrett
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?AANLkTimQ323D_YAN1Z-1uKYWLCkFqyfRvvUp6rb0K_F4>