From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jiang Liu <jiang.liu@linux.intel.com>
Subject: Re: WARNING: CPU: 4 PID: 863 at include/drm/drm_crtc.h:1577
 drm_helper_choose_encoder_dpms+0x88/0x90() - evildoer found and neutralized
Date: Tue, 6 Oct 2015 21:13:11 +0800
Message-ID: <5613C8E7.8000308@linux.intel.com>
References: <20150923160621.GA3446@pd.tnic> <20150923161839.GB3446@pd.tnic>
 <20150926164651.GA3640@pd.tnic> <560A50DC.1040505@linux.intel.com>
 <20150929105138.GA12037@nazgul.tnic> <560B9323.6000309@linux.intel.com>
 <20150930124432.GS3036@8bytes.org> <560C153C.10600@linux.intel.com>
 <20150930173619.GA3826@pd.tnic> <560F8583.2010403@linux.intel.com>
 <20151005100354.GB12506@8bytes.org>
Mime-Version: 1.0
Content-Type: text/plain; charset=windows-1252
Content-Transfer-Encoding: 7bit
Return-path: <linux-kernel-owner@vger.kernel.org>
In-Reply-To: <20151005100354.GB12506@8bytes.org>
Sender: linux-kernel-owner@vger.kernel.org
To: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@alien8.de>, Daniel Vetter <daniel@ffwll.ch>, Thomas Gleixner <tglx@linutronix.de>, Bjorn Helgaas <bhelgaas@google.com>, Alex Deucher <alexdeucher@gmail.com>, Alex Deucher <alexander.deucher@amd.com>, =?UTF-8?Q?Christian_K=c3=b6nig?= <christian.koenig@amd.com>, Maling list - DRI developers <dri-devel@lists.freedesktop.org>, lkml <linux-kernel@vger.kernel.org>
List-Id: dri-devel@lists.freedesktop.org

On 2015/10/5 18:03, Joerg Roedel wrote:
> Hi Jiang,
> 
> On Sat, Oct 03, 2015 at 03:36:35PM +0800, Jiang Liu wrote:
>> So to summary, I think we only need following change to fix the
>> regression:
>>  int pcibios_alloc_irq(struct pci_dev *dev)
>>  {
>> +	if (pci_dev_msi_enabled(dev))
>> +		return -EBUSY;
>>
>> What do you think?
> 
> Yes, that works too and has the added benefit that no driver can attach
> to the iommu device and get in the way of the driver.
> 
> Will you send the patch for this change or should I do it?
Hi Joerg,
	We are on leave for Chinese National Holiday and has limited
access to my working environment. It would be appreciated if you could
help to send out a patch for it. Otherwise I will send out a patch
within 2-3 days.
Thanks!
Gerry