From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jani Nikula Subject: Re: [PATCH v2] drm/i915: Fix lock dropping in intel_tv_detect() Date: Tue, 02 Sep 2014 10:41:05 +0300 Message-ID: <87egvuii5q.fsf@intel.com> References: <20140901085022.GB11648@nuc-i3427.alporthouse.com> <1409566060-21337-1-git-send-email-ville.syrjala@linux.intel.com> <20140901102009.GD11648@nuc-i3427.alporthouse.com> <20140901103637.GB4193@intel.com> <20140901104356.GE11648@nuc-i3427.alporthouse.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTP id 7CAEA6E41F for ; Tue, 2 Sep 2014 00:41:09 -0700 (PDT) In-Reply-To: <20140901104356.GE11648@nuc-i3427.alporthouse.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Chris Wilson , Ville =?utf-8?B?U3lyasOkbMOk?= Cc: David Airlie , Daniel Vetter , intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, Tibor Billes List-Id: intel-gfx@lists.freedesktop.org T24gTW9uLCAwMSBTZXAgMjAxNCwgQ2hyaXMgV2lsc29uIDxjaHJpc0BjaHJpcy13aWxzb24uY28u dWs+IHdyb3RlOgo+IE9uIE1vbiwgU2VwIDAxLCAyMDE0IGF0IDAxOjM2OjM3UE0gKzAzMDAsIFZp bGxlIFN5cmrDpGzDpCB3cm90ZToKPj4gT24gTW9uLCBTZXAgMDEsIDIwMTQgYXQgMTE6MjA6MDlB TSArMDEwMCwgQ2hyaXMgV2lsc29uIHdyb3RlOgo+PiA+IE9uIE1vbiwgU2VwIDAxLCAyMDE0IGF0 IDAxOjA3OjQwUE0gKzAzMDAsIHZpbGxlLnN5cmphbGFAbGludXguaW50ZWwuY29tIHdyb3RlOgo+ PiA+ID4gRnJvbTogVmlsbGUgU3lyasOkbMOkIDx2aWxsZS5zeXJqYWxhQGxpbnV4LmludGVsLmNv bT4KPj4gPiA+IAo+PiA+ID4gV2hlbiBpbnRlbF90dl9kZXRlY3QoKSBmYWlscyB0byBkbyBsb2Fk IGRldGVjdGlvbiBpdCB3b3VsZCBmb3JnZXQgdG8KPj4gPiA+IGRyb3AgdGhlIGxvY2tzIGFuZCBj bGVhbiB1cCB0aGUgYWNxdWlyZSBjb250ZXh0LiBGaXggaXQgdXAuCj4+ID4gPiAKPj4gPiA+IFRo aXMgaXMgYSByZWdyZXNzaW9uIGZyb206Cj4+ID4gPiAgY29tbWl0IDIwOGJmOWZkY2QzNTc1YWE0 YTVkNDhiM2UwMjk1ZjdjZGFmNmZjNDQKPj4gPiA+ICBBdXRob3I6IFZpbGxlIFN5cmrDpGzDpCA8 dmlsbGUuc3lyamFsYUBsaW51eC5pbnRlbC5jb20+Cj4+ID4gPiAgRGF0ZTogICBNb24gQXVnIDEx IDEzOjE1OjM1IDIwMTQgKzAzMDAKPj4gPiA+IAo+PiA+ID4gICAgIGRybS9pOTE1OiBGaXggbG9j a2luZyBmb3IgaW50ZWxfZW5hYmxlX3BpcGVfYSgpCj4+ID4gPiAKPj4gPiA+IHYyOiBNYWtlIHRo ZSBjb2RlIG1vcmUgcmVhZGFibGUgKENocmlzKQo+PiA+ID4gCj4+ID4gPiBDYzogVGlib3IgQmls bGVzIDx0YmlsbGVzQGdteC5jb20+Cj4+ID4gPiBTaWduZWQtb2ZmLWJ5OiBWaWxsZSBTeXJqw6Rs w6QgPHZpbGxlLnN5cmphbGFAbGludXguaW50ZWwuY29tPgo+PiA+IAo+PiA+IEhtbSwgaWYgd2Ug dXNlIFdBUk5fT04oKSB5b3Ugc2hvdWxkIGluaXQgdHlwZS4KPj4gCj4+IHR5cGUgaXMgYWx3YXlz IHNldCBpbiB0aGUgYnJhbmNoIHRoYXQgc2V0cyBzdGF0dXM9Y29ubmVjdGVkLgo+Cj4gQmFjayB0 byB0aGlua2luZyBhYm91dCByZWFkYWJpbGl0eSBhbmQgbWFraW5nIHN1cmUgdGhhdCB0aGUgV0FS Tl9PTgo+IG5ldmVyIGhhcHBlbnMgd2l0aCBqdXN0IGEgZ2xhbmNlLiBPdGhlcndpc2UsIHRoZSBX QVJOX09OIHdvdWxkIGJlIGJldHRlcgo+IGFzIFdBUk5fT04odW5zaWduZWQpdHlwZSA+PSBsYXN0 X3R2X3R5cGUpOyBPciBzb21ldGhpbmcuIEFud2F5LCB0YWtlCj4geW91ciBwaWNrIGFuZCBzbGFw IG15IHItYiBvbiBpdC4gOikKClZpbGxlPwoKSi4KCgo+IC1DaHJpcwo+Cj4gLS0gCj4gQ2hyaXMg V2lsc29uLCBJbnRlbCBPcGVuIFNvdXJjZSBUZWNobm9sb2d5IENlbnRyZQoKLS0gCkphbmkgTmlr dWxhLCBJbnRlbCBPcGVuIFNvdXJjZSBUZWNobm9sb2d5IENlbnRlcgpfX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fXwpJbnRlbC1nZnggbWFpbGluZyBsaXN0Cklu dGVsLWdmeEBsaXN0cy5mcmVlZGVza3RvcC5vcmcKaHR0cDovL2xpc3RzLmZyZWVkZXNrdG9wLm9y Zy9tYWlsbWFuL2xpc3RpbmZvL2ludGVsLWdmeAo= From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752768AbaIBHlL (ORCPT ); Tue, 2 Sep 2014 03:41:11 -0400 Received: from mga02.intel.com ([134.134.136.20]:45621 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750722AbaIBHlJ convert rfc822-to-8bit (ORCPT ); Tue, 2 Sep 2014 03:41:09 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.04,447,1406617200"; d="scan'208";a="566985341" From: Jani Nikula To: Chris Wilson , Ville =?utf-8?B?U3lyasOkbMOk?= Cc: intel-gfx@lists.freedesktop.org, David Airlie , Daniel Vetter , linux-kernel@vger.kernel.org, Tibor Billes Subject: Re: [PATCH v2] drm/i915: Fix lock dropping in intel_tv_detect() In-Reply-To: <20140901104356.GE11648@nuc-i3427.alporthouse.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <20140901085022.GB11648@nuc-i3427.alporthouse.com> <1409566060-21337-1-git-send-email-ville.syrjala@linux.intel.com> <20140901102009.GD11648@nuc-i3427.alporthouse.com> <20140901103637.GB4193@intel.com> <20140901104356.GE11648@nuc-i3427.alporthouse.com> User-Agent: Notmuch/0.18.1+84~g658a00e (http://notmuchmail.org) Emacs/23.4.1 (x86_64-pc-linux-gnu) Date: Tue, 02 Sep 2014 10:41:05 +0300 Message-ID: <87egvuii5q.fsf@intel.com> MIME-Version: 1.0 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 Mon, 01 Sep 2014, Chris Wilson wrote: > On Mon, Sep 01, 2014 at 01:36:37PM +0300, Ville Syrjälä wrote: >> On Mon, Sep 01, 2014 at 11:20:09AM +0100, Chris Wilson wrote: >> > On Mon, Sep 01, 2014 at 01:07:40PM +0300, ville.syrjala@linux.intel.com wrote: >> > > From: Ville Syrjälä >> > > >> > > When intel_tv_detect() fails to do load detection it would forget to >> > > drop the locks and clean up the acquire context. Fix it up. >> > > >> > > This is a regression from: >> > > commit 208bf9fdcd3575aa4a5d48b3e0295f7cdaf6fc44 >> > > Author: Ville Syrjälä >> > > Date: Mon Aug 11 13:15:35 2014 +0300 >> > > >> > > drm/i915: Fix locking for intel_enable_pipe_a() >> > > >> > > v2: Make the code more readable (Chris) >> > > >> > > Cc: Tibor Billes >> > > Signed-off-by: Ville Syrjälä >> > >> > Hmm, if we use WARN_ON() you should init type. >> >> type is always set in the branch that sets status=connected. > > Back to thinking about readability and making sure that the WARN_ON > never happens with just a glance. Otherwise, the WARN_ON would be better > as WARN_ON(unsigned)type >= last_tv_type); Or something. Anway, take > your pick and slap my r-b on it. :) Ville? J. > -Chris > > -- > Chris Wilson, Intel Open Source Technology Centre -- Jani Nikula, Intel Open Source Technology Center