From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?Q?Michel_D=c3=a4nzer?= Subject: Re: BUG caused by "Use new drm_fb_helper functions" series Date: Wed, 3 Feb 2016 18:30:54 +0900 Message-ID: <56B1C8CE.1090607@daenzer.net> References: <56AFC1F1.5080507@hurleysoftware.com> <56B03CB4.8020503@codeaurora.org> <56B0F7B3.3020704@hurleysoftware.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from mail.gna.ch (darkcity.gna.ch [195.226.6.51]) by gabe.freedesktop.org (Postfix) with ESMTP id 926B87A04F for ; Wed, 3 Feb 2016 01:31:01 -0800 (PST) In-Reply-To: <56B0F7B3.3020704@hurleysoftware.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: Peter Hurley , Archit Taneja , Daniel Vetter , Ben Skeggs Cc: Linux kernel , "dri-devel@lists.freedesktop.org" List-Id: dri-devel@lists.freedesktop.org T24gMDMuMDIuMjAxNiAwMzozOCwgUGV0ZXIgSHVybGV5IHdyb3RlOgo+IE9uIDAyLzAxLzIwMTYg MDk6MjAgUE0sIEFyY2hpdCBUYW5lamEgd3JvdGU6Cj4+IEhpIFBldGVyLAo+Pgo+PiBPbiAwMi8w Mi8yMDE2IDAyOjA3IEFNLCBQZXRlciBIdXJsZXkgd3JvdGU6Cj4+PiBIaSBBcmNoaXQsCj4+Pgo+ Pj4gSnVzdCBib290aW5nIDQuNC1yYzUrLCBJIGdvdCB0aGlzIHNwbGF0IFsxXQo+Pj4gQXQgZmly c3QgZ2xhbmNlLCB0aGlzIGFwcGVhcnMgdG8gYmUgYSBzaW1wbGUgZml4Lgo+Pgo+PiBUaGFua3Mg Zm9yIHNoYXJpbmcgdGhpcy4KPj4KPj4+Cj4+PiBIb3dldmVyLCBJJ20gY29uY2VybmVkIHRoYXQg ZmJjb24gZnVuY3Rpb25zLCB3aGljaCBtYXkgYmUgY2FsbGVkIHdpdGgKPj4+IGludGVycnVwdHMg ZGlzYWJsZWQsIGFyZSBub3cgaG9va2VkIHVwIHRvIGZiZGV2IGZ1bmN0aW9ucyB3aGljaCBtYXkg YXNzdW1lCj4+PiBpbnRlcnJ1cHRzIGFyZSBub3QgZGlzYWJsZWQgKGFzIGlzIHRoZSBjYXNlIHdp dGggY2ZiX2ltYWdlYmxpdCgpKS4KPj4KPj4gSW4gdGhlIGNhc2Ugd2hlbiBDT05GSUdfRkIgaXMg ZW5hYmxlZCwgZHJtX2ZiX2hlbHBlcl9jZmJfaW1hZ2VibGl0Cj4+IGhlbHBlciBzaW1wbHkgd3Jh cHMgYXJvdW5kIGNmZ19pbWFnZWJsaXQsIHNvIEkgZG9uJ3Qgc2VlIGhvdyB3ZSdkIGhhdmUKPj4g YW55IGRpZmZlcmVuY2UgaW4gYmVoYXZpb3VyLgo+IAo+IAo+IFNvcnJ5OyB0ZXJyaWJsZSBhdHRy aWJ1dGlvbiBvbiBteSBwYXJ0Lgo+IFRoaXMgYnVnIGNsZWFybHkgaGFzIG5vdGhpbmcgdG8gZG8g d2l0aCB0aGlzIHNlcmllcy4KPiAKPiBCdXQgYSBiZXR0ZXIgbG9vayBoYXMgbWUgd29uZGVyaW5n IGhvdyBhbGwgdGhlc2UgZ3B1cyBhcmUgc3luY2luZwo+IHRoZSBmcmFtZWJ1ZmZlciBmb3IgZGly ZWN0IGFjY2VzcyB2aWEgY2ZiX2ltYWdlYmxpdCBhbmQgZnJpZW5kcy4gSSBvbmx5IHNlZQo+IG5v dXZlYXUgYW5kIGludGVsIGdtYSBldmVuIHRyeWluZy4KClByb2JhYmx5IG5vIG90aGVyIERSTSBk cml2ZXIgdXNlcyBoYXJkd2FyZSBhY2NlbGVyYXRpb24gZm9yIGZiY29uLgoKCi0tIApFYXJ0aGxp bmcgTWljaGVsIETDpG56ZXIgICAgICAgICAgICAgICB8ICAgICAgICAgICAgICAgaHR0cDovL3d3 dy5hbWQuY29tCkxpYnJlIHNvZnR3YXJlIGVudGh1c2lhc3QgICAgICAgICAgICAgfCAgICAgICAg ICAgICBNZXNhIGFuZCBYIGRldmVsb3BlcgpfX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fXwpkcmktZGV2ZWwgbWFpbGluZyBsaXN0CmRyaS1kZXZlbEBsaXN0cy5m cmVlZGVza3RvcC5vcmcKaHR0cDovL2xpc3RzLmZyZWVkZXNrdG9wLm9yZy9tYWlsbWFuL2xpc3Rp bmZvL2RyaS1kZXZlbAo= From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753078AbcBCJbH (ORCPT ); Wed, 3 Feb 2016 04:31:07 -0500 Received: from darkcity.gna.ch ([195.226.6.51]:50708 "EHLO mail.gna.ch" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751533AbcBCJbF (ORCPT ); Wed, 3 Feb 2016 04:31:05 -0500 Subject: Re: BUG caused by "Use new drm_fb_helper functions" series To: Peter Hurley , Archit Taneja , Daniel Vetter , Ben Skeggs References: <56AFC1F1.5080507@hurleysoftware.com> <56B03CB4.8020503@codeaurora.org> <56B0F7B3.3020704@hurleysoftware.com> Cc: Linux kernel , "dri-devel@lists.freedesktop.org" From: =?UTF-8?Q?Michel_D=c3=a4nzer?= X-Enigmail-Draft-Status: N1110 Message-ID: <56B1C8CE.1090607@daenzer.net> Date: Wed, 3 Feb 2016 18:30:54 +0900 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Icedove/38.5.0 MIME-Version: 1.0 In-Reply-To: <56B0F7B3.3020704@hurleysoftware.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03.02.2016 03:38, Peter Hurley wrote: > On 02/01/2016 09:20 PM, Archit Taneja wrote: >> Hi Peter, >> >> On 02/02/2016 02:07 AM, Peter Hurley wrote: >>> Hi Archit, >>> >>> Just booting 4.4-rc5+, I got this splat [1] >>> At first glance, this appears to be a simple fix. >> >> Thanks for sharing this. >> >>> >>> However, I'm concerned that fbcon functions, which may be called with >>> interrupts disabled, are now hooked up to fbdev functions which may assume >>> interrupts are not disabled (as is the case with cfb_imageblit()). >> >> In the case when CONFIG_FB is enabled, drm_fb_helper_cfb_imageblit >> helper simply wraps around cfg_imageblit, so I don't see how we'd have >> any difference in behaviour. > > > Sorry; terrible attribution on my part. > This bug clearly has nothing to do with this series. > > But a better look has me wondering how all these gpus are syncing > the framebuffer for direct access via cfb_imageblit and friends. I only see > nouveau and intel gma even trying. Probably no other DRM driver uses hardware acceleration for fbcon. -- Earthling Michel Dänzer | http://www.amd.com Libre software enthusiast | Mesa and X developer