From mboxrd@z Thu Jan  1 00:00:00 1970
From: Baptiste Jonglez <baptiste@jonglez.org>
Subject: Re: i915_wait_request: BUG_ON(seqno == 0) triggered on
 IvyBridge
Date: Mon, 19 Dec 2011 10:14:12 +0100
Message-ID: <20111219091412.GA30888@archminux>
References: <20111219062517.GA10945@localhost>
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To: Wu Fengguang <fengguang.wu@intel.com>
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On Mon, Dec 19, 2011 at 02:25:17PM +0800, Wu Fengguang wrote:
> Hi,
> 
> I managed to trigger the below BUG_ON when switching modes in an IvyBridge box.
> 
> i915_wait_request():
> 
>         BUG_ON(seqno == 0);
> 
> The call trace is at the bottom of the following dmesg.  Any ideas?

See commit ed4a51842a9d9e618d4f4c31349b15b974dba5df on Linus' tree
(see also [1] and [2])

[1] https://lkml.org/lkml/2011/12/14/395
[2] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/903010

> Thanks,
> Fengguang

Regards,
Baptiste