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 BEEC2CCD183 for ; Thu, 16 Oct 2025 09:57:46 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 8428710E98D; Thu, 16 Oct 2025 09:57:46 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="KIpkW7Xx"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.18]) by gabe.freedesktop.org (Postfix) with ESMTPS id CC34D10E98D for ; Thu, 16 Oct 2025 09:57:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1760608665; x=1792144665; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=+KP8QFtH928S0lWilv95cGubAYZCSmXyVh/Y9aHepgc=; b=KIpkW7Xx2QPQXjOqV/bpZ8XTs0NJ8tLASXTI5mmGdyd566j9JZkAyrM4 Bpq60Crl3W21fY4bHcC/LqV79uJoIXvhKfl+cK9Qro6OTDYBjVHcwPgNX YllHEdpX50rZDE1ImslX5RSat6OcUeY9qe0xXqp4nnb9FD+R8E55Zvpk+ VwrnCgWX2D9pdkU20WOdSrgWcCncrJAUHQ9Pq6rA93rJeuKMVb6+dTeUx r6s0zMIg85DPyneqwRnYPSg5NlWFdYaz1hryOfgwWgoux87LNFp8vMbeZ pSvMpK+Z49DxtCei8T6HDgz8of0sKbe+k3dThk0sGTYvXpl70vGLR//cv g==; X-CSE-ConnectionGUID: lUHxMirLTrmiPH5Me9HzOQ== X-CSE-MsgGUID: l4ayCUzmT0O/uKjHgzZCrA== X-IronPort-AV: E=McAfee;i="6800,10657,11583"; a="62006455" X-IronPort-AV: E=Sophos;i="6.19,233,1754982000"; d="scan'208";a="62006455" Received: from orviesa009.jf.intel.com ([10.64.159.149]) by fmvoesa112.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Oct 2025 02:57:45 -0700 X-CSE-ConnectionGUID: U0Chu0qiRm6DbfvrZ22wBw== X-CSE-MsgGUID: tJqCEfy/RPy4tcC+6atmXA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.19,233,1754982000"; d="scan'208";a="181975410" Received: from jkrzyszt-mobl2.ger.corp.intel.com (HELO [10.245.245.227]) ([10.245.245.227]) by orviesa009-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Oct 2025 02:57:43 -0700 Message-ID: Date: Thu, 16 Oct 2025 10:57:40 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 3/3] drm/xe: Change return type of detect_bar2_dgfx() from s64 to u64 To: Shuicheng Lin , intel-xe@lists.freedesktop.org Cc: Rodrigo Vivi References: <20251009230239.2830207-5-shuicheng.lin@intel.com> <20251009230239.2830207-8-shuicheng.lin@intel.com> Content-Language: en-GB From: Matthew Auld In-Reply-To: <20251009230239.2830207-8-shuicheng.lin@intel.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" On 10/10/2025 00:02, Shuicheng Lin wrote: > The function never returns a negative value, and the return value is > assigned to a u64 variable. Use u64 for better type correctness > and clarity. > > v2: add assert to catch theoretical negative or zero stolen size. (Rodrigo) > > Cc: Rodrigo Vivi > Signed-off-by: Shuicheng Lin > --- > drivers/gpu/drm/xe/xe_ttm_stolen_mgr.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/xe/xe_ttm_stolen_mgr.c b/drivers/gpu/drm/xe/xe_ttm_stolen_mgr.c > index 9b00bdc8ef1a..e368b2a36bac 100644 > --- a/drivers/gpu/drm/xe/xe_ttm_stolen_mgr.c > +++ b/drivers/gpu/drm/xe/xe_ttm_stolen_mgr.c > @@ -81,7 +81,7 @@ static u32 get_wopcm_size(struct xe_device *xe) > return wopcm_size; > } > > -static s64 detect_bar2_dgfx(struct xe_device *xe, struct xe_ttm_stolen_mgr *mgr) > +static u64 detect_bar2_dgfx(struct xe_device *xe, struct xe_ttm_stolen_mgr *mgr) > { > struct xe_vram_region *tile_vram = xe_device_get_root_tile(xe)->mem.vram; > resource_size_t tile_io_start = xe_vram_region_io_start(tile_vram); > @@ -105,6 +105,8 @@ static s64 detect_bar2_dgfx(struct xe_device *xe, struct xe_ttm_stolen_mgr *mgr) > return 0; > > stolen_size = tile_size - mgr->stolen_base; > + > + xe_assert(xe, stolen_size > wopcm_size); This looks to be triggering: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/6359 > stolen_size -= wopcm_size; > > /* Verify usage fits in the actual resource available */