From owner-freebsd-mips@FreeBSD.ORG Mon Sep 16 17:17:17 2013 Return-Path: Delivered-To: freebsd-mips@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTP id 5412276E for ; Mon, 16 Sep 2013 17:17:17 +0000 (UTC) (envelope-from juli@clockworksquid.com) Received: from mail-la0-f44.google.com (mail-la0-f44.google.com [209.85.215.44]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id D2ABF2D1E for ; Mon, 16 Sep 2013 17:17:16 +0000 (UTC) Received: by mail-la0-f44.google.com with SMTP id eo20so3421963lab.31 for ; Mon, 16 Sep 2013 10:17:09 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:sender:in-reply-to:references:from :date:message-id:subject:to:cc:content-type; bh=A6wDkCouYkWgI++S6EUnWDDWzXwpZeZ3Pjl8ahdjLEc=; b=lr+TO8TXKvU6+zkh9256oC9J2Fj322Rzp8EkpTpePACi1E+LQlS/ghM0I7nGwrdng1 kCGPnsJ4lRpZbIr5ZLWImcJPT8JFBNnjndsaR1FVh7YcjOmWayucU7Bz5ciqL+z8pkYR imoI4ygZ9ipLA7LOlQ3fFmER37DAB+SP0t/96f0kUDNZSVpBZenOQ/NjlBTkgZhtz3Co sNbnBJk7AUk73w45xFih4r54IqwJ7J+MttRFUo7I4QUavPg+gX5NeWiMcU3+ywnbfJwT euYSEwAZQf4sZrPQfKfSJ/T2PYgzHyFsrmB+MOwTIUQmkTNeLh78R8unG5rG+KRHC0uC tx9A== X-Gm-Message-State: ALoCoQmQLlytTEfs0ksoY6IES1zRGYjNt0cKRsKpeEf6ZfRMnbYRmBKk7Q90WW9i9tN1/237iCHb X-Received: by 10.112.167.230 with SMTP id zr6mr2206578lbb.35.1379351829305; Mon, 16 Sep 2013 10:17:09 -0700 (PDT) MIME-Version: 1.0 Sender: juli@clockworksquid.com Received: by 10.152.23.101 with HTTP; Mon, 16 Sep 2013 10:16:49 -0700 (PDT) In-Reply-To: References: From: Juli Mallett Date: Mon, 16 Sep 2013 10:16:49 -0700 X-Google-Sender-Auth: ccPnet34Ml9ZqqJg4CA2NIOjNko Message-ID: Subject: Re: random MIPS TLB exceptions? To: Adrian Chadd Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.14 Cc: "freebsd-mips@freebsd.org" X-BeenThere: freebsd-mips@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Porting FreeBSD to MIPS List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 16 Sep 2013 17:17:17 -0000 On Mon, Sep 16, 2013 at 1:09 AM, Adrian Chadd wrote: > Hiya, > > I just saw a random panic on MIPS in kernel code where it shouldn't occur. > It hasn't happened after a reboot. > > Has anyone else seen occasional TLB exceptions? > Not enough information. There is no "MIPS" kernel and no "MIPS" platform, so it's hard to make sense of the problem space here. My instinct would be that sporadic issues of this kind could often be caused by a driver or similar, so it would be helpful to know what hardware you're using, what kernel you're running, and what kind of workload is going on. It could be something that others simply haven't hit for circumstantial reasons (say, a problem related to swapping), or based on what drivers and hardware are in-use. (Is there wireless involved? Doesn't that bring in all kinds of timers and occasional beacons that could be received? That kind of thing seems like it could result in sporadic crashes.) Did you get any kind of backtrace? Was it actually a "TLB exception" (which has a specific meaning), or do you really just mean you're seeing random panics and that you think the TLB might be implicated? What kind of TLB exception? Load, store, modify? I haven't seen anything like what you describe, I don't think, but I'm also not sure what you're describing. Hopefully we can track this down. Thanks, Juli.