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 4731EC28B2E for ; Tue, 11 Mar 2025 08:47:16 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id B111910E139; Tue, 11 Mar 2025 08:47:10 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="Q37KFYar"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.11]) by gabe.freedesktop.org (Postfix) with ESMTPS id 9820E10E139 for ; Tue, 11 Mar 2025 08:47:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1741682829; x=1773218829; h=subject:to:cc:references:from:message-id:date: mime-version:in-reply-to:content-transfer-encoding; bh=t+qxbdjqT90HBsCbN8OK5I4IJn8eZdvYfgX9yqYhxak=; b=Q37KFYarCb5iregFFYmFzCzv+6neIwLU5vG9pHa9h0oJWNx62fGUN4J2 YEI2+gqK6INN7SvEwynlP12gPCMhCr8SSeuSrI2pZoY2jx5bwt5lExVwm z5sCU8i7FgXEyOcYIhVq+w0mPoxGkwrzVdU1XpkbgRN//fv9CkLxRtDGe CUEteJvqA80nD9lB9LGshLOeFjyBWQBKDseQQge3FtVdnRxnOyvoI5Cj8 P7Bl+MRrkiUMww5wkSvnGwK0Vnav1PT3CPCDTY+Sl6FxOPrWXdXHAW5gB hJUQ0LY2HGwm0M3lUzRSlKgzKvi9GZlJ0cAWI2+X3j8nIIhjx/UcNQQvl w==; X-CSE-ConnectionGUID: CYgigZxMQ+GrIPHhBQEBFg== X-CSE-MsgGUID: urMVJcXjSkqkIFAaD/Ec6w== X-IronPort-AV: E=McAfee;i="6700,10204,11369"; a="52915726" X-IronPort-AV: E=Sophos;i="6.14,238,1736841600"; d="scan'208";a="52915726" Received: from orviesa004.jf.intel.com ([10.64.159.144]) by orvoesa103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Mar 2025 01:47:09 -0700 X-CSE-ConnectionGUID: 8bort+IOT0GtxNyE9nztbw== X-CSE-MsgGUID: TGuCczlKRySnmgtFgPixyQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.14,238,1736841600"; d="scan'208";a="125287912" Received: from ipu5-build.bj.intel.com (HELO [10.238.232.136]) ([10.238.232.136]) by orviesa004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Mar 2025 01:47:09 -0700 Subject: Re: udmabuf vmap failed (Revert "udmabuf: fix vmap_udmabuf error page set" can help) To: Huan Yang , vivek.kasireddy@intel.com Cc: linux-kernel@vger.kernel.org, christian.koenig@amd.com, dri-devel@lists.freedesktop.org References: <9172a601-c360-0d5b-ba1b-33deba430455@linux.intel.com> From: Bingbu Cao Message-ID: Date: Tue, 11 Mar 2025 16:42:13 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Huan, Thanks for your response. On 3/11/25 3:12 PM, Huan Yang wrote: > > 在 2025/3/11 14:40, Bingbu Cao 写道: >> [You don't often get email from bingbu.cao@linux.intel.com. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ] >> >> Huan Yang and Vivek, >> >> I am trying to use udmabuf for my test, and I cannot vmap the udmabuf >> buffers now. vmap_pfn_apply() will report a warning to complain that >> the pfns are invalid. >> I dump the pfn numbers as below: >> [ 3365.399641] pg[0] pfn 1148695 >> [ 3365.399642] pg[1] pfn 1145057 >> [ 3365.399642] pg[2] pfn 1134070 >> [ 3365.399643] pg[3] pfn 1148700 >> [ 3365.399643] pg[4] pfn 1144871 >> [ 3365.399643] pg[5] pfn 1408686 >> [ 3365.399643] pg[6] pfn 1408683 >> ... >> [ 3365.399660] WARNING: CPU: 3 PID: 2772 at mm/vmalloc.c:3489 vmap_pfn_apply+0xb7/0xd0 >> [ 3365.399667] Modules linked in:... >> [ 3365.399750] CPU: 3 UID: 0 PID: 2772 Comm: drm-test Not tainted 6.13.0-rc2-rvp #845 >> [ 3365.399752] Hardware name: Intel Corporation Client Platform/xxxx, BIOS xxxFWI1.R00.3221.D83.2408120121 08/12/2024 >> [ 3365.399753] RIP: 0010:vmap_pfn_apply+0xb7/0xd0 >> [ 3365.399755] Code: 5b 41 5c 41 5d 5d c3 cc cc cc cc 48 21 c3 eb d1 48 21 c3 48 23 3d 31 c0 26 02 eb c5 48 c7 c7 c4 3c 20 a8 e8 5b c0 d8 ff eb 8a <0f> 0b b8 ea ff ff ff 5b 41 5c 41 5d 5d c3 cc cc cc cc 0f 1f 80 00 >> [ 3365.399756] RSP: 0018:ffffb9b50c32fad0 EFLAGS: 00010202 >> [ 3365.399757] RAX: 0000000000000001 RBX: 0000000000118717 RCX: 0000000000000000 >> [ 3365.399758] RDX: 0000000080000000 RSI: ffffb9b50c358000 RDI: 00000000ffffffff >> [ 3365.399758] RBP: ffffb9b50c32fae8 R08: ffffb9b50c32fbd0 R09: 0000000000000001 >> [ 3365.399759] R10: ffff941602479288 R11: 0000000000000000 R12: ffffb9b50c32fbd0 >> [ 3365.399759] R13: ffff941618665ac0 R14: ffffb9b50c358000 R15: ffff941618665ac8 >> [ 3365.399760] FS: 00007ff9e9ddd740(0000) GS:ffff94196f780000(0000) knlGS:0000000000000000 >> [ 3365.399760] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >> [ 3365.399761] CR2: 000055fda5dc69d9 CR3: 00000001544de003 CR4: 0000000000f72ef0 >> [ 3365.399762] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 >> [ 3365.399762] DR3: 0000000000000000 DR6: 00000000ffff07f0 DR7: 0000000000000400 >> [ 3365.399763] PKRU: 55555554 >> [ 3365.399763] Call Trace: >> [ 3365.399765] >> [ 3365.399769] ? show_regs+0x6d/0x80 >> [ 3365.399773] ? __warn+0x97/0x160 >> [ 3365.399777] ? vmap_pfn_apply+0xb7/0xd0 >> [ 3365.399777] ? report_bug+0x1ec/0x240 >> [ 3365.399782] ? handle_bug+0x63/0xa0 >> [ 3365.399784] ? exc_invalid_op+0x1d/0x80 >> [ 3365.399785] ? asm_exc_invalid_op+0x1f/0x30 >> [ 3365.399790] ? vmap_pfn_apply+0xb7/0xd0 >> [ 3365.399791] __apply_to_page_range+0x522/0x8a0 >> [ 3365.399794] ? __pfx_vmap_pfn_apply+0x10/0x10 >> [ 3365.399795] apply_to_page_range+0x18/0x20 >> [ 3365.399796] vmap_pfn+0x77/0xd0 >> [ 3365.399797] vmap_udmabuf+0xc5/0x110 >> [ 3365.399802] dma_buf_vmap+0x96/0x130 >> >> I did an experiment to revert 18d7de823b7150344d242c3677e65d68c5271b04, >> then I can vmap the pages. Could you help what's wrong with that? > > Sorry for that, as I reviewed pfn_valid, that's someting wired: > > /** > * pfn_valid - check if there is a valid memory map entry for a PFN > * @pfn: the page frame number to check > * > * Check if there is a valid memory map entry aka struct page for the @pfn. > * Note, that availability of the memory map entry does not imply that > * there is actual usable memory at that @pfn. The struct page may > * represent a hole or an unusable page frame. > * > * Return: 1 for PFNs that have memory map entries and 0 otherwise > */ > > So, if pfn valid, it's return 1, else 0. So mean, only 1 is a valid pfn. But vmap_pfn_apply in there: > > static int vmap_pfn_apply(pte_t *pte, unsigned long addr, void *private) > { > struct vmap_pfn_data *data = private; > unsigned long pfn = data->pfns[data->idx]; > pte_t ptent; > > if (WARN_ON_ONCE(pfn_valid(pfn))) > return -EINVAL; > > ptent = pte_mkspecial(pfn_pte(pfn, data->prot)); > set_pte_at(&init_mm, addr, pte, ptent); > > data->idx++; > return 0; > } > > Do it give a wrong check? maybe should fix by: I guess not, it looks more like warning when you trying to vmap a pfn which already took a valid entry in pte. However, the MM code is so complex for me, just my guess. :) > > static int vmap_pfn_apply(pte_t *pte, unsigned long addr, void *private) > { > struct vmap_pfn_data *data = private; > unsigned long pfn = data->pfns[data->idx]; > pte_t ptent; > > - if (WARN_ON_ONCE(pfn_valid(pfn))) > + if (WARN_ON_ONCE(!pfn_valid(pfn))) > return -EINVAL; > > ptent = pte_mkspecial(pfn_pte(pfn, data->prot)); > set_pte_at(&init_mm, addr, pte, ptent); > > data->idx++; > return 0; > } > > Please help me check it, also, you can apply this and then check it.:) > >> >> >> -- >> Best regards, >> Bingbu Cao -- Best regards, Bingbu Cao