From: David Miller <davem@davemloft.net>
To: jkacur@gmail.com
Cc: linux-rt-users@vger.kernel.org, linux-kernel@vger.kernel.org,
mingo@elte.hu, tglx@linutronix.de, rostedt@goodmis.org,
a.p.zijlstra@chello.nl
Subject: Re: [PATCH] BUG: using smp_processor_id() in preemptible [00000000] code: caller is __qdisc_run
Date: Mon, 11 Aug 2008 14:00:14 -0700 (PDT) [thread overview]
Message-ID: <20080811.140014.94581847.davem@davemloft.net> (raw)
In-Reply-To: <520f0cf10808110611y62f6a4e2v94a0d0cde1d5d79d@mail.gmail.com>
From: "John Kacur" <jkacur@gmail.com>
Date: Mon, 11 Aug 2008 15:11:46 +0200
> __qdisc_run() calls qdisc_restart() which calls
> handle_dev_cpu_collision(skb, dev, q); and then the problem shows up
> here:
> __get_cpu_var(netdev_rx_stat).cpu_collision++;
>
> The solution is to disable interrupts around the above increment. Here
> is an attached patch to do so. (Thank's to Peter Zijlstra for help in
> the analysis and dropping the answer in my lap, so if I got it right
> it is due to his help, but if I messed it up, then I did that part all
> by myself.)
__qdisc_run() always runs in software interrupt context,
so I guess this is some problem with the -rt stuff running
software interrupts in threads?
next prev parent reply other threads:[~2008-08-11 21:00 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-08-11 13:11 John Kacur
2008-08-11 21:00 ` David Miller [this message]
2008-08-11 21:09 ` Peter Zijlstra
2008-08-11 21:23 ` David Miller
2008-08-12 1:22 ` Steven Rostedt
2008-08-12 2:06 ` Gregory Haskins
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