From: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
To: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: "David S. Miller" <davem@davemloft.net>,
"Eric Dumazet" <edumazet@google.com>,
netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
"Alexandre FOURNIER" <alexandre.fournier@wisp-e.com>,
"Ezequiel Garcia" <ezequiel.garcia@free-electrons.com>,
"Marcin Wojtas" <mw@semihalf.com>,
"Gregory Clément" <gregory.clement@free-electrons.com>
Subject: Re: RCU stall in af_unix.c, should use spin_lock_irqsave?
Date: Tue, 21 Oct 2014 12:13:04 +0200 [thread overview]
Message-ID: <20141021121304.076d5acd@free-electrons.com> (raw)
In-Reply-To: <1413886132.32553.14.camel@localhost>
Dear Hannes Frederic Sowa,
On Tue, 21 Oct 2014 12:08:52 +0200, Hannes Frederic Sowa wrote:
> On Di, 2014-10-21 at 10:03 +0200, Thomas Petazzoni wrote:
> > So, the question is: is this patch the correct solution (but then other
> > usage of spin_lock in af_unix.c might also need fixing) ? Or is the
> > network driver at fault?
>
> It feels like a false positive. Do you see one core spinning tightly on
> a lock? Does the system get unusable?
Interrupts are still enabled (for example, sysrq are still working),
but scheduling no longer takes place (all processes are blocked).
Best regards,
Thomas
--
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
prev parent reply other threads:[~2014-10-21 10:13 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-10-21 8:03 RCU stall in af_unix.c, should use spin_lock_irqsave? Thomas Petazzoni
2014-10-21 10:04 ` Eric Dumazet
2014-10-21 10:10 ` Thomas Petazzoni
2014-10-21 10:28 ` Eric Dumazet
2014-10-21 11:58 ` Thomas Petazzoni
2014-10-21 10:08 ` Hannes Frederic Sowa
2014-10-21 10:13 ` Thomas Petazzoni [this message]
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