Date: Mon, 22 Apr 2013 15:16:16 -0400 From: Juan Mojica <jmojica@gmail.com> To: Gleb Smirnoff <glebius@freebsd.org> Cc: FreeBSD Net <freebsd-net@freebsd.org> Subject: Re: ARP: Error Message in if_ether.c "arprequest: cannot find matching address" Message-ID: <CAPKuH-xH=Ev=yxzHen_XAtBjPUMHaKDH2VXp8=1kRUmjBwTM3w@mail.gmail.com> In-Reply-To: <CAPKuH-wQnyxdddMozTN328V3U_GLpiCOp-nuKiYEKXO-FWhmVg@mail.gmail.com> References: <CAPKuH-w4ugf4KSWBKMoURbNsSrs1O-XNmWdn47VKn9MkCOgRDw@mail.gmail.com> <20130422095759.GC76816@FreeBSD.org> <CAPKuH-wQnyxdddMozTN328V3U_GLpiCOp-nuKiYEKXO-FWhmVg@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
I'll provide my revision shortly.
On Mon, Apr 22, 2013 at 2:48 PM, Juan Mojica <jmojica@gmail.com> wrote:
> Thanks Gleb. I do not believe this path can triggered by an incoming
> frame. I am planning on adding a KASSERT here to get a core when we
> exercise this code in our debug images.
>
> -Juan
>
>
> On Mon, Apr 22, 2013 at 5:57 AM, Gleb Smirnoff <glebius@freebsd.org>wrote:
>
>> On Wed, Apr 17, 2013 at 08:46:42AM -0400, Juan Mojica wrote:
>> J> We manage to hit the following message with some regularity.
>> J>
>> J> arprequest: cannot find matching address
>> J>
>> J> The code shows a printf:
>> J>
>> J> printf("%s: cannot find matching address\n", __func__);
>> J>
>> J>
>> J> Any reason this is a printf and not a
>> J>
>> J> log(LOG_ERR,
>> J>
>> J> The only things I can come up with are:
>> J>
>> J> a) it is a really severe and should be printed out, which if that is
>> the
>> J> case why isn't there an assert there?
>> J> b) whoops, that should probably be a log(LOG_ERR,
>> J> On our end we need to figure out exactly why we're intermittently
>> hitting
>> J> this patch of code.
>>
>> Can you please try this patch? Let's see what's going on.
>>
>> printf()ing in kernel is especially unsafe when the event can be triggered
>> remotely. The arprequest() is called on output path of a packet, however
>> I'm not sure that it can't be triggered by incoming packet.
>>
>> --
>> Totus tuus, Glebius.
>>
>
>
>
> --
> Juan Mojica
> Email: jmojica@gmail.com
>
--
Juan Mojica
Email: jmojica@gmail.com
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CAPKuH-xH=Ev=yxzHen_XAtBjPUMHaKDH2VXp8=1kRUmjBwTM3w>