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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 4324EE7717D for ; Wed, 11 Dec 2024 15:18:16 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id C9F7F10E1C2; Wed, 11 Dec 2024 15:18:15 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="e/MVwDri"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.9]) by gabe.freedesktop.org (Postfix) with ESMTPS id C8F5410E1C2 for ; Wed, 11 Dec 2024 15:18:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1733930295; x=1765466295; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=ukrGri52IST/ae3Q334P2JT6KHhzXSR/ereBf4Z9bGI=; b=e/MVwDrikwIC9jypVY/wmN0z353A9x76/BslCKAx/QQj2cKukdEqkfx5 OUbWdnLzYHE1pkpekDUx21YkpCyNUJX62qOyCmMebDd4OdhuTm4YE4G4n F+pyttrTF8P4zUvY6rNL616X6oiXSopdjZjt+wvrtVQ0h8uLE+jQhi90d jlGxqoHzOxaHJmMvDLJZnNqi3bWoev9zu6uBxBNFBPj6iZ5w8kOug+/9D x7m6i2+Nz2pwjxDlrS2zkUnwkVsB4RKf5TZoqoqb3zTOaGsp/p+WkILWm Ptivqxa09AUu0upGmsuXe8PFRKE27P6kBnm5M7GMo4rcjh95XcafwOpds w==; X-CSE-ConnectionGUID: /WvC3/I9TkOxkaLB0Kx6Kg== X-CSE-MsgGUID: yhaySuh9SGCQJNwNimB5qQ== X-IronPort-AV: E=McAfee;i="6700,10204,11283"; a="56793829" X-IronPort-AV: E=Sophos;i="6.12,225,1728975600"; d="scan'208";a="56793829" Received: from orviesa009.jf.intel.com ([10.64.159.149]) by orvoesa101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Dec 2024 07:18:15 -0800 X-CSE-ConnectionGUID: Bl3Vd0hpRUir07zzi9e/Mg== X-CSE-MsgGUID: iha50d25R2+Y50+Uixt7iw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.12,225,1728975600"; d="scan'208";a="95704322" Received: from jkrzyszt-mobl2.ger.corp.intel.com (HELO intel.com) ([10.245.246.26]) by orviesa009-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Dec 2024 07:18:10 -0800 Date: Wed, 11 Dec 2024 16:18:06 +0100 From: Andi Shyti To: Krzysztof Karas Cc: intel-gfx@lists.freedesktop.org, Michal Wajdeczko , Andi Shyti , Imre Deak , Jani Nikula , Rodrigo Vivi Subject: Re: [PATCH v2] drm/display: use ERR_PTR on DP tunnel manager creation fail Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Hi Krzysztof, On Wed, Dec 11, 2024 at 02:52:20PM +0000, Krzysztof Karas wrote: > Instead of returning a generic NULL on error from drm_dp_tunnel_mgr_create(), > use error pointers with informative codes. This will also trigger IS_ERR() in > current caller (intel_dp_tunnerl_mgr_init()) instead of bypassing it via NULL > pointer. I was about to suggest fixing either this or his counterpart in the header file. Please send this in a series along with the previous patch in order to let people understand why you are sending this. Besides, I think you can improve the explanation here, which is the different behaviour of drm_dp_tunnel_mgr_create() depending on the CONFIG_DRM_DISPLAY_DP_TUNNEL config flag. You can add to both of them my r-b. Did you check who is maintaining this file? Andi > v2: use error codes inside drm_dp_tunnel_mgr_create() instead of handling > on caller's side (Michal, Imre) > > Signed-off-by: Krzysztof Karas > --- > drivers/gpu/drm/display/drm_dp_tunnel.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/drivers/gpu/drm/display/drm_dp_tunnel.c b/drivers/gpu/drm/display/drm_dp_tunnel.c > index 48b2df120086..90fe07a89260 100644 > --- a/drivers/gpu/drm/display/drm_dp_tunnel.c > +++ b/drivers/gpu/drm/display/drm_dp_tunnel.c > @@ -1896,8 +1896,8 @@ static void destroy_mgr(struct drm_dp_tunnel_mgr *mgr) > * > * Creates a DP tunnel manager for @dev. > * > - * Returns a pointer to the tunnel manager if created successfully or NULL in > - * case of an error. > + * Returns a pointer to the tunnel manager if created successfully or error > + * pointer in case of failure. > */ > struct drm_dp_tunnel_mgr * > drm_dp_tunnel_mgr_create(struct drm_device *dev, int max_group_count) > @@ -1907,7 +1907,7 @@ drm_dp_tunnel_mgr_create(struct drm_device *dev, int max_group_count) > > mgr = kzalloc(sizeof(*mgr), GFP_KERNEL); > if (!mgr) > - return NULL; > + return ERR_PTR(-ENOMEM); > > mgr->dev = dev; > init_waitqueue_head(&mgr->bw_req_queue); > @@ -1916,7 +1916,7 @@ drm_dp_tunnel_mgr_create(struct drm_device *dev, int max_group_count) > if (!mgr->groups) { > kfree(mgr); > > - return NULL; > + return ERR_PTR(-ENOMEM); > } > > #ifdef CONFIG_DRM_DISPLAY_DP_TUNNEL_STATE_DEBUG > @@ -1927,7 +1927,7 @@ drm_dp_tunnel_mgr_create(struct drm_device *dev, int max_group_count) > if (!init_group(mgr, &mgr->groups[i])) { > destroy_mgr(mgr); > > - return NULL; > + return ERR_PTR(-ENOMEM); > } > > mgr->group_count++; > -- > 2.34.1