From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jani Nikula Subject: Re: [PATCH AUTOSEL for 4.9 36/56] drm/i915: Fix the level 0 max_wm hack on VLV/CHV Date: Fri, 17 Nov 2017 13:28:05 +0200 Message-ID: <87bmk15em2.fsf@intel.com> References: <20171115024521.5884-1-alexander.levin@verizon.com> <20171115024521.5884-36-alexander.levin@verizon.com> <20171115110805.GX10981@intel.com> <20171115164451.ogl3ku6qr3cfnbk7@sasha-lappy> <20171115170320.GK10981@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <20171115170320.GK10981@intel.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Ville =?utf-8?B?U3lyasOkbMOk?= , alexander.levin@verizon.com Cc: "stable@vger.kernel.org" , intel-gfx@lists.freedesktop.org, "linux-kernel@vger.kernel.org" , dri-devel@lists.freedesktop.org, Greg KH List-Id: dri-devel@lists.freedesktop.org CkNjOiBHcmVnCgpPbiBXZWQsIDE1IE5vdiAyMDE3LCBWaWxsZSBTeXJqw6Rsw6QgPHZpbGxlLnN5 cmphbGFAbGludXguaW50ZWwuY29tPiB3cm90ZToKPiBPbiBXZWQsIE5vdiAxNSwgMjAxNyBhdCAw NDo0NDo1NFBNICswMDAwLCBhbGV4YW5kZXIubGV2aW5AdmVyaXpvbi5jb20gd3JvdGU6Cj4+IE9u IFdlZCwgTm92IDE1LCAyMDE3IGF0IDAxOjA4OjA1UE0gKzAyMDAsIFZpbGxlIFN5cmrDpGzDpCB3 cm90ZToKPj4gPk9uIFdlZCwgTm92IDE1LCAyMDE3IGF0IDAyOjQ1OjQzQU0gKzAwMDAsIGFsZXhh bmRlci5sZXZpbkB2ZXJpem9uLmNvbSB3cm90ZToKPj4gPj4gRnJvbTogVmlsbGUgU3lyasODwqRs w4PCpCA8dmlsbGUuc3lyamFsYUBsaW51eC5pbnRlbC5jb20+Cj4+ID4+Cj4+ID4+IFsgVXBzdHJl YW0gY29tbWl0IDFiZTRkMzc5M2Q1YTkzZGFkZGNkOWJlNjU3YzQyOWIzOGFkNzUwYTMgXQo+PiA+ Pgo+PiA+PiBUaGUgd2F0ZXJtYXJrIHNob3VsZCBuZXZlciBleGNlZWQgdGhlIEZJRk8gc2l6ZSwg c28gd2UgbmVlZCB0bwo+PiA+PiBjaGVjayBhZ2FpbnN0IHRoZSBjdXJyZW50IEZJRk8gc2l6ZSBp bnN0ZWFkIG9mIHRoZSB0aGVvcmV0aWNhbAo+PiA+PiBtYXhpbXVtIHdoZW4gd2UgY2xhbXAgdGhl IGxldmVsIDAgd2F0ZXJtYXJrLgo+PiA+Pgo+PiA+PiBTaWduZWQtb2ZmLWJ5OiBWaWxsZSBTeXJq w4PCpGzDg8KkIDx2aWxsZS5zeXJqYWxhQGxpbnV4LmludGVsLmNvbT4KPj4gPj4gTGluazogaHR0 cHM6Ly91cmxkZWZlbnNlLnByb29mcG9pbnQuY29tL3YyL3VybD91PWh0dHAtM0FfX3BhdGNod29y ay5mcmVlZGVza3RvcC5vcmdfcGF0Y2hfbXNnaWRfMTQ4MDM1NDYzNy0yRDE0MjA5LTJENC0yRGdp dC0yRHNlbmQtMkRlbWFpbC0yRHZpbGxlLnN5cmphbGEtNDBsaW51eC5pbnRlbC5jb20mZD1Ed0lE QXcmYz11ZEJUUnZGdlhDNURocWc3VUhwSmxQcHMzbVozTFJ4cGI2X18wUG9tQlRRJnI9YlV0YWFD OW1sQmlqNE9qRUdfRC1LUHVsXzMzNWF6WXpmQzRSamdvbW9ibyZtPWl1UHRVYXItVkVHYkgxam1W SF9VVHI0QzAyWDhmbWpIVWZOWWl4LVljMFkmcz1oYV9GMHpQM0ExQXp0cDVTNWU2X2JxZGhpdXVQ WGhuMGRSV1E1OHZ2M0lzJmU9Cj4+ID4+IFJldmlld2VkLWJ5OiBNYWFydGVuIExhbmtob3JzdCA8 bWFhcnRlbi5sYW5raG9yc3RAbGludXguaW50ZWwuY29tPgo+PiA+PiBTaWduZWQtb2ZmLWJ5OiBT YXNoYSBMZXZpbiA8YWxleGFuZGVyLmxldmluQHZlcml6b24uY29tPgo+PiA+Cj4+ID5XaHkgYXJl IHRoZXNlIHBhdGNoZXMgYmVpbmcgcHJvcG9zZWQgZm9yIHN0YWJsZT8gVGhleSdyZSBub3Qgc3Ry YWlnaHQgdXAKPj4gPmZpeGVzIGZvciBrbm93biBpc3N1ZXMsIGFuZCB0aGVyZSdzIGFsd2F5cyBh IGNoYW5jZSB0aGF0IHNvbWV0aGluZyB3aWxsCj4+ID5icmVhay4gV2hvIGlzIGRvaW5nIHRoZSBx YSBvbiB0aGlzPwo+PiAKPj4gSGkgVmlsbGUsCj4+IAo+PiBUaGV5IHdlcmUgc2VsZWN0ZWQgYXV0 b21hdGljYWxseSBhcyBwYXJ0IG9mIGEgbmV3IHByb2Nlc3Mgd2UncmUgdHJ5aW5nCj4+IG91dC4g SWYgeW91IGRpc2FncmVlIHdpdGggdGhlIHNlbGVjdGlvbiBJJ2QgYmUgaGFwcHkgdG8gZHJvcCBp dC4KPgo+IEhvdyBkb2VzIHRoYXQgYXV0b21hdGljIHByb2Nlc3MgZGVjaWRlIHRoYXQgYSBwYXRj aCBzaG91bGQgYmUgYmFja3BvcnRlZD8KPgo+IGRybSBhbmQgaTkxNSBhcmUgdmVyeSBmYXN0IG1v dmluZyB0YXJnZXRzIHNvIHVuaW50ZW5kZWQgc2lkZSBlZmZlY3RzIGZyb20KPiBiYWNrcG9ydGVk IHBhdGNoZXMgaXMgYSByZWFsIHBvc3NpYmlsaXR5LiBTbyBJIHdvdWxkIHJlY29tbWVuZCBhZ2Fp bnN0Cj4gYmFja3BvcnRpbmcgYW55dGhpbmcgdGhhdCBpc24ndCBmaXhpbmcgYSByZWFsIGlzc3Vl IGFmZmVjdGluZyB1c2Vycy4gV2UKPiBkbyB0cnkgdG8gYWRkIHRoZSBjYzpzdGFibGUgdG8gc3Vj aCBwYXRjaGVzLgoKQWdyZWVkLgoKRmlyc3QsIEkgdGhpbmsgYW4gYXV0b21hdGljIGJhY2twb3J0 IHByb2Nlc3MgaXMgYWdhaW5zdCB0aGUgc3RhYmxlCmtlcm5lbCBydWxlcyAoZS5nLiAiSXQgbXVz dCBmaXggYSByZWFsIGJ1ZyB0aGF0IGJvdGhlcnMgcGVvcGxlIikuCgpTZWNvbmQsIHdlIGNhbid0 IGFuZCB3b24ndCB0YWtlIGFueSByZXNwb25zaWJpbGl0eSBmb3IgYmFja3BvcnRzIHdlCmRpZG4n dCBpbmRpY2F0ZSB3aXRoIENjOiBzdGFibGUsIGEgRml4ZXM6IHRhZywgb3IgYSBzcGVjaWZpYyBi YWNrcG9ydApyZXF1ZXN0LgoKSWYgeW91IHRoaW5rIHRoZXJlJ3MgYSBjb21taXQgdGhhdCBzaG91 bGQgYmUgYmFja3BvcnRlZCBhbmQgaXMga25vd24gdG8KZml4IGEgdXNlciB2aXNpYmxlIGlzc3Vl IChhcyBwZXIgdGhlIHN0YWJsZSBydWxlcyEpLCBwbGVhc2UgY2hlY2sgd2l0aAp1cyBmaXJzdC4K CgpCUiwKSmFuaS4KCi0tIApKYW5pIE5pa3VsYSwgSW50ZWwgT3BlbiBTb3VyY2UgVGVjaG5vbG9n eSBDZW50ZXIKX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18K SW50ZWwtZ2Z4IG1haWxpbmcgbGlzdApJbnRlbC1nZnhAbGlzdHMuZnJlZWRlc2t0b3Aub3JnCmh0 dHBzOi8vbGlzdHMuZnJlZWRlc2t0b3Aub3JnL21haWxtYW4vbGlzdGluZm8vaW50ZWwtZ2Z4Cg== From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753968AbdKQL0y convert rfc822-to-8bit (ORCPT ); Fri, 17 Nov 2017 06:26:54 -0500 Received: from mga11.intel.com ([192.55.52.93]:64824 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753778AbdKQL0p (ORCPT ); Fri, 17 Nov 2017 06:26:45 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.44,408,1505804400"; d="scan'208";a="3746255" From: Jani Nikula To: Ville =?utf-8?B?U3lyasOkbMOk?= , alexander.levin@verizon.com Cc: dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, "linux-kernel\@vger.kernel.org" , "stable\@vger.kernel.org" , Greg KH Subject: Re: [PATCH AUTOSEL for 4.9 36/56] drm/i915: Fix the level 0 max_wm hack on VLV/CHV In-Reply-To: <20171115170320.GK10981@intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <20171115024521.5884-1-alexander.levin@verizon.com> <20171115024521.5884-36-alexander.levin@verizon.com> <20171115110805.GX10981@intel.com> <20171115164451.ogl3ku6qr3cfnbk7@sasha-lappy> <20171115170320.GK10981@intel.com> Date: Fri, 17 Nov 2017 13:28:05 +0200 Message-ID: <87bmk15em2.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 Cc: Greg On Wed, 15 Nov 2017, Ville Syrjälä wrote: > On Wed, Nov 15, 2017 at 04:44:54PM +0000, alexander.levin@verizon.com wrote: >> On Wed, Nov 15, 2017 at 01:08:05PM +0200, Ville Syrjälä wrote: >> >On Wed, Nov 15, 2017 at 02:45:43AM +0000, alexander.levin@verizon.com wrote: >> >> From: Ville Syrjälä >> >> >> >> [ Upstream commit 1be4d3793d5a93daddcd9be657c429b38ad750a3 ] >> >> >> >> The watermark should never exceed the FIFO size, so we need to >> >> check against the current FIFO size instead of the theoretical >> >> maximum when we clamp the level 0 watermark. >> >> >> >> Signed-off-by: Ville Syrjälä >> >> Link: https://urldefense.proofpoint.com/v2/url?u=http-3A__patchwork.freedesktop.org_patch_msgid_1480354637-2D14209-2D4-2Dgit-2Dsend-2Demail-2Dville.syrjala-40linux.intel.com&d=DwIDAw&c=udBTRvFvXC5Dhqg7UHpJlPps3mZ3LRxpb6__0PomBTQ&r=bUtaaC9mlBij4OjEG_D-KPul_335azYzfC4Rjgomobo&m=iuPtUar-VEGbH1jmVH_UTr4C02X8fmjHUfNYix-Yc0Y&s=ha_F0zP3A1Aztp5S5e6_bqdhiuuPXhn0dRWQ58vv3Is&e= >> >> Reviewed-by: Maarten Lankhorst >> >> Signed-off-by: Sasha Levin >> > >> >Why are these patches being proposed for stable? They're not straight up >> >fixes for known issues, and there's always a chance that something will >> >break. Who is doing the qa on this? >> >> Hi Ville, >> >> They were selected automatically as part of a new process we're trying >> out. If you disagree with the selection I'd be happy to drop it. > > How does that automatic process decide that a patch should be backported? > > drm and i915 are very fast moving targets so unintended side effects from > backported patches is a real possibility. So I would recommend against > backporting anything that isn't fixing a real issue affecting users. We > do try to add the cc:stable to such patches. Agreed. First, I think an automatic backport process is against the stable kernel rules (e.g. "It must fix a real bug that bothers people"). Second, we can't and won't take any responsibility for backports we didn't indicate with Cc: stable, a Fixes: tag, or a specific backport request. If you think there's a commit that should be backported and is known to fix a user visible issue (as per the stable rules!), please check with us first. BR, Jani. -- Jani Nikula, Intel Open Source Technology Center