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=-6.6 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 autolearn=unavailable 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 4EEBDC352A3 for ; Tue, 11 Feb 2020 17:02:43 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 270F82082F for ; Tue, 11 Feb 2020 17:02:43 +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="Uf6lwNUR" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 270F82082F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ffwll.ch Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 754A76E182; Tue, 11 Feb 2020 17:02:40 +0000 (UTC) Received: from mail-wr1-x441.google.com (mail-wr1-x441.google.com [IPv6:2a00:1450:4864:20::441]) by gabe.freedesktop.org (Postfix) with ESMTPS id D01DA6E02F for ; Tue, 11 Feb 2020 17:02:38 +0000 (UTC) Received: by mail-wr1-x441.google.com with SMTP id u6so13365597wrt.0 for ; Tue, 11 Feb 2020 09:02:38 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to; bh=3R9Yae05oMwB+6rODdVuzCeJG7eybKxFzo4VVXSkB6M=; b=Uf6lwNUR1Ud/dQ0z1+UxHFVPD56GxEWIj0KA2E4A1d1Ea9DDRN03maxXpf5xB7MhN3 fliY1vKy4BMoMJbhZLjWrSxF0hozgNXHBwr8Vg2+MNuNHt8uHlM4ILmsr0tYSbFWdxr3 fe8pp8pDOVFmj2bbAxVWeknRLtoFfkoYRJsVY= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=3R9Yae05oMwB+6rODdVuzCeJG7eybKxFzo4VVXSkB6M=; b=To6oXNhLNsofct4UztgNgpRi6SBhqGuZG8fhTl3AcNC0CeYc0LVQAU74HZci/x2XPp 83dlokWCuZOthhXfrHEE8hzxkcL7lLMtbNId+2+E1pIK/PkkGcJ79IgMAOm7hPXhVZ8+ BaeSPrOCZj+QtD7AfeR2d/imSMw0FhxzmM0q3ExNQ1wMvvAzV+bjwOkC3sARQCjC/bV3 DEK/2qCmnMffCvrjbNZ24TP0UhbPeTqVdqZP4HD9qR6JlZvsn5Z8l5EtBiJfn4OssZBu op2biO9inYJaAzvs/6eA295Cxd5sBIqyAfUccOiTASe+VwWBNYP3tR8V6zqkT8YPpHQc beaQ== X-Gm-Message-State: APjAAAX8We2SygrIHFdhWREjrIdgHWpsudEfEdRa5BoU6Ys1ZsH663GI HkYKH4aHGZTXUVqQvO4v+r51EQ== X-Google-Smtp-Source: APXvYqxRiMLj9baAWBBP0koFCvwdrFel/5+tec/2tMw1l3p7xsth7R5LrGB9fX8P0kbN1ASuIXocLQ== X-Received: by 2002:a5d:5148:: with SMTP id u8mr9919627wrt.132.1581440556852; Tue, 11 Feb 2020 09:02:36 -0800 (PST) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id x11sm4469923wmg.46.2020.02.11.09.02.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 11 Feb 2020 09:02:35 -0800 (PST) Date: Tue, 11 Feb 2020 18:02:33 +0100 From: Daniel Vetter To: Ville Syrjala Message-ID: <20200211170233.GL2363188@phenom.ffwll.local> References: <20200211162208.16224-1-ville.syrjala@linux.intel.com> <20200211162208.16224-6-ville.syrjala@linux.intel.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200211162208.16224-6-ville.syrjala@linux.intel.com> X-Operating-System: Linux phenom 5.3.0-3-amd64 Subject: Re: [Intel-gfx] [PATCH v3 5/7] drm: Validate encoder->possible_clones X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: intel-gfx@lists.freedesktop.org, Thomas Zimmermann , dri-devel@lists.freedesktop.org Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Tue, Feb 11, 2020 at 06:22:06PM +0200, Ville Syrjala wrote: > From: Ville Syrj=E4l=E4 > = > Many drivers are populating encoder->possible_clones wrong. Let's > persuade them to get it right by adding some loud WARNs. > = > We'll cross check the bits between any two encoders. So either > both encoders can clone with the other, or neither can. > = > We'll also complain about effectively empty possible_clones, and > possible_clones containing bits for encoders that don't exist. > = > v2: encoder->possible_clones now includes the encoder itelf > v3: Move to drm_mode_config_validate() (Daniel) > Document that you get a WARN when this is wrong (Daniel) > Extract full_encoder_mask() > = > Acked-by: Thomas Zimmermann > Cc: Daniel Vetter > Signed-off-by: Ville Syrj=E4l=E4 I wonder whether we should start to have some unit tests for stuff like this, like set up broken driver, make sure we have a WARN in dmesg. But ideally we'd do that with the mocking stuff Kunit hopefully has soon. > --- > drivers/gpu/drm/drm_mode_config.c | 40 +++++++++++++++++++++++++++++++ > include/drm/drm_encoder.h | 2 ++ > 2 files changed, 42 insertions(+) > = > diff --git a/drivers/gpu/drm/drm_mode_config.c b/drivers/gpu/drm/drm_mode= _config.c > index 75e357c7e84d..afc91447293a 100644 > --- a/drivers/gpu/drm/drm_mode_config.c > +++ b/drivers/gpu/drm/drm_mode_config.c > @@ -533,6 +533,17 @@ void drm_mode_config_cleanup(struct drm_device *dev) > } > EXPORT_SYMBOL(drm_mode_config_cleanup); > = > +static u32 full_encoder_mask(struct drm_device *dev) > +{ > + struct drm_encoder *encoder; > + u32 encoder_mask =3D 0; > + > + drm_for_each_encoder(encoder, dev) > + encoder_mask |=3D drm_encoder_mask(encoder); > + > + return encoder_mask; > +} > + > /* > * For some reason we want the encoder itself included in > * possible_clones. Make life easy for drivers by allowing them > @@ -544,10 +555,39 @@ static void fixup_encoder_possible_clones(struct dr= m_encoder *encoder) > encoder->possible_clones =3D drm_encoder_mask(encoder); > } > = > +static void validate_encoder_possible_clones(struct drm_encoder *encoder) > +{ > + struct drm_device *dev =3D encoder->dev; > + u32 encoder_mask =3D full_encoder_mask(dev); > + struct drm_encoder *other; > + > + drm_for_each_encoder(other, dev) { > + WARN(!(encoder->possible_clones & drm_encoder_mask(other)) !=3D > + !(other->possible_clones & drm_encoder_mask(encoder)), Bikeshed: !! as canonical "make this a bool value" might be slightly clearer, but whatever. > + "possible_clones mismatch: " > + "[ENCODER:%d:%s] mask=3D0x%x possible_clones=3D0x%x vs. " > + "[ENCODER:%d:%s] mask=3D0x%x possible_clones=3D0x%x\n", > + encoder->base.id, encoder->name, > + drm_encoder_mask(encoder), encoder->possible_clones, > + other->base.id, other->name, > + drm_encoder_mask(other), other->possible_clones); > + } > + > + WARN((encoder->possible_clones & drm_encoder_mask(encoder)) =3D=3D 0 || > + (encoder->possible_clones & ~encoder_mask) !=3D 0, > + "Bogus possible_clones: " > + "[ENCODER:%d:%s] possible_clones=3D0x%x (full encoder mask=3D0x%x)= \n", > + encoder->base.id, encoder->name, > + encoder->possible_clones, encoder_mask); > +} Since it's next to each another double-checking that the fixup did add the self-clone is probably too much :-) > + > void drm_mode_config_validate(struct drm_device *dev) > { > struct drm_encoder *encoder; > = > drm_for_each_encoder(encoder, dev) > fixup_encoder_possible_clones(encoder); > + > + drm_for_each_encoder(encoder, dev) > + validate_encoder_possible_clones(encoder); > } > diff --git a/include/drm/drm_encoder.h b/include/drm/drm_encoder.h > index 22d6cdf729f1..3741963b9587 100644 > --- a/include/drm/drm_encoder.h > +++ b/include/drm/drm_encoder.h > @@ -163,6 +163,8 @@ struct drm_encoder { > * any cloning it can leave @possible_clones set to 0. The core will > * automagically fix this up by setting the bit for the encoder itself. > * > + * You will get a WARN if you get this wrong in the driver. Nice. Reviewed-by: Daniel Vetter > + * > * Note that since encoder objects can't be hotplugged the assigned ind= ices > * are stable and hence known before registering all objects. > */ > -- = > 2.24.1 > = -- = Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx