From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= Subject: Re: drivers/gpu/drm/i915/display/intel_display.c:3934 skl_plane_stride() error: testing array offset 'color_plane' after use. Date: Mon, 16 Sep 2019 15:43:40 +0300 Message-ID: <20190916124340.GF1208@intel.com> References: <20190914040858.GT20699@kadam> <87lfuou27c.fsf@intel.com> <20190916075913.GZ20699@kadam> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by gabe.freedesktop.org (Postfix) with ESMTPS id 297146E96B for ; Mon, 16 Sep 2019 12:43:44 +0000 (UTC) Content-Disposition: inline In-Reply-To: <20190916075913.GZ20699@kadam> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Dan Carpenter Cc: Jani Nikula , intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, kbuild@01.org, kbuild-all@01.org List-Id: intel-gfx@lists.freedesktop.org T24gTW9uLCBTZXAgMTYsIDIwMTkgYXQgMTA6NTk6MTNBTSArMDMwMCwgRGFuIENhcnBlbnRlciB3 cm90ZToKPiBPbiBNb24sIFNlcCAxNiwgMjAxOSBhdCAxMDozMTozNUFNICswMzAwLCBKYW5pIE5p a3VsYSB3cm90ZToKPiA+IE9uIFNhdCwgMTQgU2VwIDIwMTksIERhbiBDYXJwZW50ZXIgPGRhbi5j YXJwZW50ZXJAb3JhY2xlLmNvbT4gd3JvdGU6Cj4gPiA+IHRyZWU6ICAgaHR0cHM6Ly9rZXJuZWwu Z29vZ2xlc291cmNlLmNvbS9wdWIvc2NtL2xpbnV4L2tlcm5lbC9naXQvdG9ydmFsZHMvbGludXgu Z2l0IG1hc3Rlcgo+ID4gPiBoZWFkOiAgIGE3Zjg5NjE2YjczNzY0OTU0MjRmNjgyYjYwODZlMGMz OTFhODlhMWQKPiA+ID4gY29tbWl0OiBkZjA1NjZhNjQxZjk1OTEwOGMxNTJiZTc0OGEwYTU4Nzk0 MjgwZTBlIGRybS9pOTE1OiBtb3ZlIG1vZGVzZXR0aW5nIGNvcmUgY29kZSB1bmRlciBkaXNwbGF5 Lwo+ID4gPiBkYXRlOiAgIDMgbW9udGhzIGFnbwo+ID4gPgo+ID4gPiBJZiB5b3UgZml4IHRoZSBp c3N1ZSwga2luZGx5IGFkZCBmb2xsb3dpbmcgdGFnCj4gPiA+IFJlcG9ydGVkLWJ5OiBrYnVpbGQg dGVzdCByb2JvdCA8bGtwQGludGVsLmNvbT4KPiA+ID4gUmVwb3J0ZWQtYnk6IERhbiBDYXJwZW50 ZXIgPGRhbi5jYXJwZW50ZXJAb3JhY2xlLmNvbT4KPiA+ID4KPiA+ID4gTmV3IHNtYXRjaCB3YXJu aW5nczoKPiA+ID4gZHJpdmVycy9ncHUvZHJtL2k5MTUvZGlzcGxheS9pbnRlbF9kaXNwbGF5LmM6 MzkzNCBza2xfcGxhbmVfc3RyaWRlKCkgZXJyb3I6IHRlc3RpbmcgYXJyYXkgb2Zmc2V0ICdjb2xv cl9wbGFuZScgYWZ0ZXIgdXNlLgoKVGhlIGNvZGUgbG9va3MgZmluZSB0byBtZS4gaW50IGNvbG9y X3BsYW5lIGlzIDAgb3IgMSBzbyB3ZSBrbm93CnRoZSBjb2xvcl9wbGFuZVtdIGFycmF5IGlzIGhh cyBlbm91Z2ggZWxlbWVudHMuIEJ1dCBpZgpmYi0+bnVtX3BsYW5lcz09MSB3ZSBkb24ndCBhY3R1 YWxseSB3YW50IHRvIGxvb2sgYXQgY29sb3JfcGxhbmVbMV0uCgo+ID4gPiBkcml2ZXJzL2dwdS9k cm0vaTkxNS9kaXNwbGF5L2ludGVsX2Rpc3BsYXkuYzoxNjMyOCBpbnRlbF9zYW5pdGl6ZV9lbmNv ZGVyKCkgZXJyb3I6IHdlIHByZXZpb3VzbHkgYXNzdW1lZCAnY3J0YycgY291bGQgYmUgbnVsbCAo c2VlIGxpbmUgMTYzMTgpCgpJZiBjcnRjX3N0YXRlIT1OVUxMIHRoZW4gY3J0YyE9TlVMTC4gTG9v a3Mgc2FmZSB0byBtZS4KCj4gPiAKPiA+IE9kZCwgd2hhdCBjaGFuZ2VkIHRvIHByb3Zva2UgdGhl IHdhcm5pbmdzIG5vdz8gT3IgaXMgdGhlIHNtYXRjaCB0ZXN0Cj4gPiBuZXc/Cj4gPiAKPiAKPiBJ dCBsb29rcyBsaWtlIHRoZSBjcm9zcyBmdW5jdGlvbiBEQiBpcyBvdXQgb2YgZGF0YSBzbGlnaHRs eS4gIE1heWJlCj4gYmVjYXVzZSB0aGUgZmlsZSBtb3ZlZD8gIE9uIG15IHN5c3RlbSBTbWF0Y2gg a25vd3MgdGhhdCBjb2xvcl9wbGFuZSBpcwo+IDAtMSBhbmQgcGxhbmVfc3RhdGUtPmNvbG9yX3Bs YW5lW10gaXMgYSB0d28gZWxlbWVudCBhcnJheSBzbyBpdCBkb2Vzbid0Cj4gcHJpbnQgdGhlIHdh cm5pbmcuCj4gCj4gVGhpcyBpcyBqdXN0IGEgc2FuaXR5IGNoZWNrIHdoaWNoIGlzIG5ldmVyIHRy aWdnZXJlZC4gIFNob3VsZCB0aGUgc2FuaXR5Cj4gY2hlY2sgYmUgbW92ZT8gIFdoYXQgd2FzIG9y aWdpbmFsbHkgaW50ZW5kZWQ/ICBJdCdzIGhhcmQgdG8gc2F5Lgo+IAo+IHJlZ2FyZHMsCj4gZGFu IGNhcnBlbnRlcgoKLS0gClZpbGxlIFN5cmrDpGzDpApJbnRlbApfX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fXwpJbnRlbC1nZnggbWFpbGluZyBsaXN0CkludGVs LWdmeEBsaXN0cy5mcmVlZGVza3RvcC5vcmcKaHR0cHM6Ly9saXN0cy5mcmVlZGVza3RvcC5vcmcv bWFpbG1hbi9saXN0aW5mby9pbnRlbC1nZng= 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=-7.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 C5D2DC49ED7 for ; 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Mon, 16 Sep 2019 15:43:40 +0300 Date: Mon, 16 Sep 2019 15:43:40 +0300 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= To: Dan Carpenter Cc: Jani Nikula , kbuild@01.org, kbuild-all@01.org, linux-kernel@vger.kernel.org, Chris Wilson , intel-gfx@lists.freedesktop.org Subject: Re: drivers/gpu/drm/i915/display/intel_display.c:3934 skl_plane_stride() error: testing array offset 'color_plane' after use. Message-ID: <20190916124340.GF1208@intel.com> References: <20190914040858.GT20699@kadam> <87lfuou27c.fsf@intel.com> <20190916075913.GZ20699@kadam> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20190916075913.GZ20699@kadam> 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 Mon, Sep 16, 2019 at 10:59:13AM +0300, Dan Carpenter wrote: > On Mon, Sep 16, 2019 at 10:31:35AM +0300, Jani Nikula wrote: > > On Sat, 14 Sep 2019, Dan Carpenter wrote: > > > tree: https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux.git master > > > head: a7f89616b7376495424f682b6086e0c391a89a1d > > > commit: df0566a641f959108c152be748a0a58794280e0e drm/i915: move modesetting core code under display/ > > > date: 3 months ago > > > > > > If you fix the issue, kindly add following tag > > > Reported-by: kbuild test robot > > > Reported-by: Dan Carpenter > > > > > > New smatch warnings: > > > drivers/gpu/drm/i915/display/intel_display.c:3934 skl_plane_stride() error: testing array offset 'color_plane' after use. The code looks fine to me. int color_plane is 0 or 1 so we know the color_plane[] array is has enough elements. But if fb->num_planes==1 we don't actually want to look at color_plane[1]. > > > drivers/gpu/drm/i915/display/intel_display.c:16328 intel_sanitize_encoder() error: we previously assumed 'crtc' could be null (see line 16318) If crtc_state!=NULL then crtc!=NULL. Looks safe to me. > > > > Odd, what changed to provoke the warnings now? Or is the smatch test > > new? > > > > It looks like the cross function DB is out of data slightly. Maybe > because the file moved? On my system Smatch knows that color_plane is > 0-1 and plane_state->color_plane[] is a two element array so it doesn't > print the warning. > > This is just a sanity check which is never triggered. Should the sanity > check be move? What was originally intended? It's hard to say. > > regards, > dan carpenter -- Ville Syrjälä Intel