From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1752068AbbJCJfn (ORCPT <rfc822;w@1wt.eu>);
	Sat, 3 Oct 2015 05:35:43 -0400
Received: from mail.skyhub.de ([78.46.96.112]:42908 "EHLO mail.skyhub.de"
	rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
	id S1751894AbbJCJfl (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
	Sat, 3 Oct 2015 05:35:41 -0400
Date: Sat, 3 Oct 2015 11:35:38 +0200
From: Borislav Petkov <bp@alien8.de>
To: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>, 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>,
        Christian =?utf-8?B?S8O2bmln?= <christian.koenig@amd.com>,
        Maling list - DRI developers 
	<dri-devel@lists.freedesktop.org>,
        lkml <linux-kernel@vger.kernel.org>
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
Message-ID: <20151003093538.GA3786@pd.tnic>
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>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
In-Reply-To: <560F8583.2010403@linux.intel.com>
User-Agent: Mutt/1.5.23 (2014-03-12)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Sat, Oct 03, 2015 at 03:36:35PM +0800, Jiang Liu wrote:
> The above change is not needed, pcibios_disable_irq() will
> first check !pci_has_managed_irq(dev) before actually freeing
> PCI irq. pci_has_managed_irq(dev) only returns true if
> pcibios_alloc_irq() succeeds.
> 
> 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?

Yap, that works too. I've got only this ontop of 4.3+tip:

---
diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index dc78a4a9a466..a4687aa6c1fb 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -675,6 +675,9 @@ int pcibios_add_device(struct pci_dev *dev)
 
 int pcibios_alloc_irq(struct pci_dev *dev)
 {
+	if (pci_dev_msi_enabled(dev))
+		return -EBUSY;
+
 	return pcibios_enable_irq(dev);
 }
 
---

and it suspend+resumed fine.

I guess it is time for Joerg to write a proper patch. :-)

Thanks.

-- 
Regards/Gruss,
    Boris.

ECO tip #101: Trim your mails when you reply.