From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DD513C31E49 for ; Wed, 19 Jun 2019 07:49:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9D5712075E for ; Wed, 19 Jun 2019 07:49:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=ffwll.ch header.i=@ffwll.ch header.b="jWHFk6Xq" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731241AbfFSHtD (ORCPT ); Wed, 19 Jun 2019 03:49:03 -0400 Received: from mail-ed1-f65.google.com ([209.85.208.65]:33241 "EHLO mail-ed1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725980AbfFSHtC (ORCPT ); Wed, 19 Jun 2019 03:49:02 -0400 Received: by mail-ed1-f65.google.com with SMTP id i11so25796470edq.0 for ; Wed, 19 Jun 2019 00:49:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=sender:date:from:to:cc:subject:message-id:mail-followup-to :references:mime-version:content-disposition :content-transfer-encoding:in-reply-to:user-agent; bh=9yRPqLsy9SzgWIOIK5gO9H41NqMgtH7z8Lf0epnTSe8=; b=jWHFk6XqsoYXocFpSE0gn/gHZJ/0TrxElZKm42Ipe0ZdlxBiXBmyo9fX4/WGgeDDO3 8AYZ0F+ufO1zlDHVBmH9vwwSvpWZI8HJCpZq3I4Sx2ZL54GWsm81cgHwZAzplxF8c3Me oI3KswqH2dD74mtl53UCCeWZ6zPk1dUxbOPMc= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :mail-followup-to:references:mime-version:content-disposition :content-transfer-encoding:in-reply-to:user-agent; bh=9yRPqLsy9SzgWIOIK5gO9H41NqMgtH7z8Lf0epnTSe8=; b=XcQyYj4AT9CzjAaaBQ3hz778vsC3sFThe5DTwcJDTRYgXqspeFYrPbdcGzuZ11UDkt NRqhb2GEU/tUVYNMH/0EE+Qr9fIroy/Y+LJ0jb7jKA9zPbgNQOB6NntG9Vtr9/KlJuKB FATLYuFEmUKLIka11dbVakg0bCEAWG6x8lyiGliIkFEDSX7fI6aF6qjdAtYPH958fsDs 2hGr2+eqEClHcUK49kxQaLlG8sQYN2yKnIBVAV4V1a5a9lqyilvT0glfxhnqvCqeULAx hnrQiZcC8TcoobfHJquyUbedrN3tthdMJZCOANRmqPeDYOium0dBxMjVwAWWMmM/ilrR w3jw== X-Gm-Message-State: APjAAAXmJZXe+nqDQIKORzoFVwTfTas5QtCExELVX858Vh7Uns19frfW o4Forgr/cdu48FObu83RJNB+IQ== X-Google-Smtp-Source: APXvYqzcQ/qJVFreUUsYyuaxNjvBsBySdJhnXRVOLZg1dyo7u4fZwHatDwiE/NN42tCU6BsQTm39fg== X-Received: by 2002:a50:883b:: with SMTP id b56mr36295341edb.178.1560930540342; Wed, 19 Jun 2019 00:49:00 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:569e:0:3106:d637:d723:e855]) by smtp.gmail.com with ESMTPSA id x4sm5546030eda.22.2019.06.19.00.48.59 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Wed, 19 Jun 2019 00:48:59 -0700 (PDT) Date: Wed, 19 Jun 2019 09:48:56 +0200 From: Daniel Vetter To: Rodrigo Siqueira Cc: Maarten Lankhorst , Maxime Ripard , Sean Paul , David Airlie , Daniel Vetter , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org, intel-gfx@lists.freedesktop.org Subject: Re: [PATCH V4] drm/drm_vblank: Change EINVAL by the correct errno Message-ID: <20190619074856.GJ12905@phenom.ffwll.local> Mail-Followup-To: Rodrigo Siqueira , Maarten Lankhorst , Maxime Ripard , Sean Paul , David Airlie , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org, intel-gfx@lists.freedesktop.org References: <20190619020750.swzerehjbvx6sbk2@smtp.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20190619020750.swzerehjbvx6sbk2@smtp.gmail.com> X-Operating-System: Linux phenom 4.19.0-5-amd64 User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 18, 2019 at 11:07:50PM -0300, Rodrigo Siqueira wrote: > For historical reason, the function drm_wait_vblank_ioctl always return > -EINVAL if something gets wrong. This scenario limits the flexibility > for the userspace make detailed verification of the problem and take > some action. In particular, the validation of “if (!dev->irq_enabled)” > in the drm_wait_vblank_ioctl is responsible for checking if the driver > support vblank or not. If the driver does not support VBlank, the > function drm_wait_vblank_ioctl returns EINVAL which does not represent > the real issue; this patch changes this behavior by return EOPNOTSUPP. > Additionally, some operations are unsupported by this function, and > returns EINVAL; this patch also changes the return value to EOPNOTSUPP > in this case. Lastly, the function drm_wait_vblank_ioctl is invoked by > libdrm, which is used by many compositors; because of this, it is > important to check if this change breaks any compositor. In this sense, > the following projects were examined: > > * Drm-hwcomposer > * Kwin > * Sway > * Wlroots > * Wayland-core > * Weston > * Xorg (67 different drivers) > > For each repository the verification happened in three steps: > > * Update the main branch > * Look for any occurrence "drmWaitVBlank" with the command: > git grep -n "drmWaitVBlank" > * Look in the git history of the project with the command: > git log -SdrmWaitVBlank > > Finally, none of the above projects validate the use of EINVAL which > make safe, at least for these projects, to change the return values. > > Change since V3: > - Return EINVAL for _DRM_VBLANK_SIGNAL (Daniel) > > Change since V2: > Daniel Vetter and Chris Wilson > - Replace ENOTTY by EOPNOTSUPP > - Return EINVAL if the parameters are wrong > Reviewed-by: Daniel Vetter Apologies for the confusion on the last time around. btw if someone tells you "r-b (or a-b) with these changes", then just apply the r-b/a-b tag next time around. Otherwise people will re-review the same thing over and over again. -Daniel > Signed-off-by: Rodrigo Siqueira > --- > drivers/gpu/drm/drm_vblank.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c > index 603ab105125d..bed233361614 100644 > --- a/drivers/gpu/drm/drm_vblank.c > +++ b/drivers/gpu/drm/drm_vblank.c > @@ -1582,7 +1582,7 @@ int drm_wait_vblank_ioctl(struct drm_device *dev, void *data, > unsigned int flags, pipe, high_pipe; > > if (!dev->irq_enabled) > - return -EINVAL; > + return -EOPNOTSUPP; > > if (vblwait->request.type & _DRM_VBLANK_SIGNAL) > return -EINVAL; > -- > 2.21.0 -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Vetter Date: Wed, 19 Jun 2019 07:48:56 +0000 Subject: Re: [PATCH V4] drm/drm_vblank: Change EINVAL by the correct errno Message-Id: <20190619074856.GJ12905@phenom.ffwll.local> List-Id: References: <20190619020750.swzerehjbvx6sbk2@smtp.gmail.com> In-Reply-To: <20190619020750.swzerehjbvx6sbk2@smtp.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit To: Rodrigo Siqueira Cc: Maxime Ripard , kernel-janitors@vger.kernel.org, intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, David Airlie On Tue, Jun 18, 2019 at 11:07:50PM -0300, Rodrigo Siqueira wrote: > For historical reason, the function drm_wait_vblank_ioctl always return > -EINVAL if something gets wrong. This scenario limits the flexibility > for the userspace make detailed verification of the problem and take > some action. In particular, the validation of “if (!dev->irq_enabled)” > in the drm_wait_vblank_ioctl is responsible for checking if the driver > support vblank or not. If the driver does not support VBlank, the > function drm_wait_vblank_ioctl returns EINVAL which does not represent > the real issue; this patch changes this behavior by return EOPNOTSUPP. > Additionally, some operations are unsupported by this function, and > returns EINVAL; this patch also changes the return value to EOPNOTSUPP > in this case. Lastly, the function drm_wait_vblank_ioctl is invoked by > libdrm, which is used by many compositors; because of this, it is > important to check if this change breaks any compositor. In this sense, > the following projects were examined: > > * Drm-hwcomposer > * Kwin > * Sway > * Wlroots > * Wayland-core > * Weston > * Xorg (67 different drivers) > > For each repository the verification happened in three steps: > > * Update the main branch > * Look for any occurrence "drmWaitVBlank" with the command: > git grep -n "drmWaitVBlank" > * Look in the git history of the project with the command: > git log -SdrmWaitVBlank > > Finally, none of the above projects validate the use of EINVAL which > make safe, at least for these projects, to change the return values. > > Change since V3: > - Return EINVAL for _DRM_VBLANK_SIGNAL (Daniel) > > Change since V2: > Daniel Vetter and Chris Wilson > - Replace ENOTTY by EOPNOTSUPP > - Return EINVAL if the parameters are wrong > Reviewed-by: Daniel Vetter Apologies for the confusion on the last time around. btw if someone tells you "r-b (or a-b) with these changes", then just apply the r-b/a-b tag next time around. Otherwise people will re-review the same thing over and over again. -Daniel > Signed-off-by: Rodrigo Siqueira > --- > drivers/gpu/drm/drm_vblank.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c > index 603ab105125d..bed233361614 100644 > --- a/drivers/gpu/drm/drm_vblank.c > +++ b/drivers/gpu/drm/drm_vblank.c > @@ -1582,7 +1582,7 @@ int drm_wait_vblank_ioctl(struct drm_device *dev, void *data, > unsigned int flags, pipe, high_pipe; > > if (!dev->irq_enabled) > - return -EINVAL; > + return -EOPNOTSUPP; > > if (vblwait->request.type & _DRM_VBLANK_SIGNAL) > return -EINVAL; > -- > 2.21.0 -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Vetter Subject: Re: [PATCH V4] drm/drm_vblank: Change EINVAL by the correct errno Date: Wed, 19 Jun 2019 09:48:56 +0200 Message-ID: <20190619074856.GJ12905@phenom.ffwll.local> References: <20190619020750.swzerehjbvx6sbk2@smtp.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Content-Disposition: inline In-Reply-To: <20190619020750.swzerehjbvx6sbk2@smtp.gmail.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Rodrigo Siqueira Cc: Maxime Ripard , kernel-janitors@vger.kernel.org, intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, David Airlie List-Id: dri-devel@lists.freedesktop.org T24gVHVlLCBKdW4gMTgsIDIwMTkgYXQgMTE6MDc6NTBQTSAtMDMwMCwgUm9kcmlnbyBTaXF1ZWly YSB3cm90ZToKPiBGb3IgaGlzdG9yaWNhbCByZWFzb24sIHRoZSBmdW5jdGlvbiBkcm1fd2FpdF92 YmxhbmtfaW9jdGwgYWx3YXlzIHJldHVybgo+IC1FSU5WQUwgaWYgc29tZXRoaW5nIGdldHMgd3Jv bmcuIFRoaXMgc2NlbmFyaW8gbGltaXRzIHRoZSBmbGV4aWJpbGl0eQo+IGZvciB0aGUgdXNlcnNw YWNlIG1ha2UgZGV0YWlsZWQgdmVyaWZpY2F0aW9uIG9mIHRoZSBwcm9ibGVtIGFuZCB0YWtlCj4g c29tZSBhY3Rpb24uIEluIHBhcnRpY3VsYXIsIHRoZSB2YWxpZGF0aW9uIG9mIOKAnGlmICghZGV2 LT5pcnFfZW5hYmxlZCnigJ0KPiBpbiB0aGUgZHJtX3dhaXRfdmJsYW5rX2lvY3RsIGlzIHJlc3Bv bnNpYmxlIGZvciBjaGVja2luZyBpZiB0aGUgZHJpdmVyCj4gc3VwcG9ydCB2Ymxhbmsgb3Igbm90 LiBJZiB0aGUgZHJpdmVyIGRvZXMgbm90IHN1cHBvcnQgVkJsYW5rLCB0aGUKPiBmdW5jdGlvbiBk cm1fd2FpdF92YmxhbmtfaW9jdGwgcmV0dXJucyBFSU5WQUwgd2hpY2ggZG9lcyBub3QgcmVwcmVz ZW50Cj4gdGhlIHJlYWwgaXNzdWU7IHRoaXMgcGF0Y2ggY2hhbmdlcyB0aGlzIGJlaGF2aW9yIGJ5 IHJldHVybiBFT1BOT1RTVVBQLgo+IEFkZGl0aW9uYWxseSwgc29tZSBvcGVyYXRpb25zIGFyZSB1 bnN1cHBvcnRlZCBieSB0aGlzIGZ1bmN0aW9uLCBhbmQKPiByZXR1cm5zIEVJTlZBTDsgdGhpcyBw YXRjaCBhbHNvIGNoYW5nZXMgdGhlIHJldHVybiB2YWx1ZSB0byBFT1BOT1RTVVBQCj4gaW4gdGhp cyBjYXNlLiBMYXN0bHksIHRoZSBmdW5jdGlvbiBkcm1fd2FpdF92YmxhbmtfaW9jdGwgaXMgaW52 b2tlZCBieQo+IGxpYmRybSwgd2hpY2ggaXMgdXNlZCBieSBtYW55IGNvbXBvc2l0b3JzOyBiZWNh dXNlIG9mIHRoaXMsIGl0IGlzCj4gaW1wb3J0YW50IHRvIGNoZWNrIGlmIHRoaXMgY2hhbmdlIGJy ZWFrcyBhbnkgY29tcG9zaXRvci4gSW4gdGhpcyBzZW5zZSwKPiB0aGUgZm9sbG93aW5nIHByb2pl Y3RzIHdlcmUgZXhhbWluZWQ6Cj4gCj4gKiBEcm0taHdjb21wb3Nlcgo+ICogS3dpbgo+ICogU3dh eQo+ICogV2xyb290cwo+ICogV2F5bGFuZC1jb3JlCj4gKiBXZXN0b24KPiAqIFhvcmcgKDY3IGRp ZmZlcmVudCBkcml2ZXJzKQo+IAo+IEZvciBlYWNoIHJlcG9zaXRvcnkgdGhlIHZlcmlmaWNhdGlv biBoYXBwZW5lZCBpbiB0aHJlZSBzdGVwczoKPiAKPiAqIFVwZGF0ZSB0aGUgbWFpbiBicmFuY2gK PiAqIExvb2sgZm9yIGFueSBvY2N1cnJlbmNlICJkcm1XYWl0VkJsYW5rIiB3aXRoIHRoZSBjb21t YW5kOgo+ICAgZ2l0IGdyZXAgLW4gImRybVdhaXRWQmxhbmsiCj4gKiBMb29rIGluIHRoZSBnaXQg aGlzdG9yeSBvZiB0aGUgcHJvamVjdCB3aXRoIHRoZSBjb21tYW5kOgo+ICAgZ2l0IGxvZyAtU2Ry bVdhaXRWQmxhbmsKPiAKPiBGaW5hbGx5LCBub25lIG9mIHRoZSBhYm92ZSBwcm9qZWN0cyB2YWxp ZGF0ZSB0aGUgdXNlIG9mIEVJTlZBTCB3aGljaAo+IG1ha2Ugc2FmZSwgYXQgbGVhc3QgZm9yIHRo ZXNlIHByb2plY3RzLCB0byBjaGFuZ2UgdGhlIHJldHVybiB2YWx1ZXMuCj4gCj4gQ2hhbmdlIHNp bmNlIFYzOgo+ICAtIFJldHVybiBFSU5WQUwgZm9yIF9EUk1fVkJMQU5LX1NJR05BTCAoRGFuaWVs KQo+IAo+IENoYW5nZSBzaW5jZSBWMjoKPiAgRGFuaWVsIFZldHRlciBhbmQgQ2hyaXMgV2lsc29u Cj4gIC0gUmVwbGFjZSBFTk9UVFkgYnkgRU9QTk9UU1VQUAo+ICAtIFJldHVybiBFSU5WQUwgaWYg dGhlIHBhcmFtZXRlcnMgYXJlIHdyb25nCj4gCgpSZXZpZXdlZC1ieTogRGFuaWVsIFZldHRlciA8 ZGFuaWVsLnZldHRlckBmZndsbC5jaD4KCkFwb2xvZ2llcyBmb3IgdGhlIGNvbmZ1c2lvbiBvbiB0 aGUgbGFzdCB0aW1lIGFyb3VuZC4gYnR3IGlmIHNvbWVvbmUgdGVsbHMKeW91ICJyLWIgKG9yIGEt Yikgd2l0aCB0aGVzZSBjaGFuZ2VzIiwgdGhlbiBqdXN0IGFwcGx5IHRoZSByLWIvYS1iIHRhZwpu ZXh0IHRpbWUgYXJvdW5kLiBPdGhlcndpc2UgcGVvcGxlIHdpbGwgcmUtcmV2aWV3IHRoZSBzYW1l IHRoaW5nIG92ZXIgYW5kCm92ZXIgYWdhaW4uCi1EYW5pZWwKCj4gU2lnbmVkLW9mZi1ieTogUm9k cmlnbyBTaXF1ZWlyYSA8cm9kcmlnb3NpcXVlaXJhbWVsb0BnbWFpbC5jb20+Cj4gLS0tCj4gIGRy aXZlcnMvZ3B1L2RybS9kcm1fdmJsYW5rLmMgfCAyICstCj4gIDEgZmlsZSBjaGFuZ2VkLCAxIGlu c2VydGlvbigrKSwgMSBkZWxldGlvbigtKQo+IAo+IGRpZmYgLS1naXQgYS9kcml2ZXJzL2dwdS9k cm0vZHJtX3ZibGFuay5jIGIvZHJpdmVycy9ncHUvZHJtL2RybV92YmxhbmsuYwo+IGluZGV4IDYw M2FiMTA1MTI1ZC4uYmVkMjMzMzYxNjE0IDEwMDY0NAo+IC0tLSBhL2RyaXZlcnMvZ3B1L2RybS9k cm1fdmJsYW5rLmMKPiArKysgYi9kcml2ZXJzL2dwdS9kcm0vZHJtX3ZibGFuay5jCj4gQEAgLTE1 ODIsNyArMTU4Miw3IEBAIGludCBkcm1fd2FpdF92YmxhbmtfaW9jdGwoc3RydWN0IGRybV9kZXZp Y2UgKmRldiwgdm9pZCAqZGF0YSwKPiAgCXVuc2lnbmVkIGludCBmbGFncywgcGlwZSwgaGlnaF9w aXBlOwo+ICAKPiAgCWlmICghZGV2LT5pcnFfZW5hYmxlZCkKPiAtCQlyZXR1cm4gLUVJTlZBTDsK PiArCQlyZXR1cm4gLUVPUE5PVFNVUFA7Cj4gIAo+ICAJaWYgKHZibHdhaXQtPnJlcXVlc3QudHlw ZSAmIF9EUk1fVkJMQU5LX1NJR05BTCkKPiAgCQlyZXR1cm4gLUVJTlZBTDsKPiAtLSAKPiAyLjIx LjAKCi0tIApEYW5pZWwgVmV0dGVyClNvZnR3YXJlIEVuZ2luZWVyLCBJbnRlbCBDb3Jwb3JhdGlv bgpodHRwOi8vYmxvZy5mZndsbC5jaApfX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fXwpJbnRlbC1nZnggbWFpbGluZyBsaXN0CkludGVsLWdmeEBsaXN0cy5mcmVl ZGVza3RvcC5vcmcKaHR0cHM6Ly9saXN0cy5mcmVlZGVza3RvcC5vcmcvbWFpbG1hbi9saXN0aW5m by9pbnRlbC1nZng=