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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 AC683C1B0F2 for ; Wed, 20 Jun 2018 08:42:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 57A95208B0 for ; Wed, 20 Jun 2018 08:42:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 57A95208B0 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932770AbeFTImW (ORCPT ); Wed, 20 Jun 2018 04:42:22 -0400 Received: from mga01.intel.com ([192.55.52.88]:47651 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750793AbeFTImP (ORCPT ); Wed, 20 Jun 2018 04:42:15 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 20 Jun 2018 01:39:46 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,246,1526367600"; d="scan'208";a="48491287" Received: from lteixeir-mobl.ger.corp.intel.com (HELO [10.252.35.108]) ([10.252.35.108]) by fmsmga007.fm.intel.com with ESMTP; 20 Jun 2018 01:39:44 -0700 Subject: Re: [PATCH] drm: fix pci_dev root device is NULL without check. To: Caicai , gustavo@padovan.org Cc: seanpaul@chromium.org, airlied@linux.ie, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Alex Deucher References: <20180619074756.19047-1-caizhaopeng@deepin.com> From: Maarten Lankhorst Message-ID: Date: Wed, 20 Jun 2018 10:39:43 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 MIME-Version: 1.0 In-Reply-To: <20180619074756.19047-1-caizhaopeng@deepin.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Op 19-06-18 om 09:47 schreef Caicai: > on my laptop with ATI Radeon R7 350 graphics card,I found root was NULL,we should check > the device before get/set pcie speed cap mask. Here is my messages. > [ 8.996093] [drm] radeon kernel modesetting enabled. > [ 8.996093] [drm] initializing kernel modesetting (OLAND 0x1002:0x6610 0x174B:0xA00B). > [ 8.996093] [drm] register mmio base: 0x10000000 > [ 8.996093] [drm] register mmio size: 262144 > [ 9.121093] ATOM BIOS: C55001 > [ 9.121093] [drm] GPU not posted. posting now... > [ 9.125000] radeon 0001:20:00.0: VRAM: 2048M 0x0000000000000000 - 0x000000007FFFFFFF (2048M used) > [ 9.125000] radeon 0001:20:00.0: GTT: 2048M 0x0000000080000000 - 0x00000000FFFFFFFF > [ 9.125000] [drm] Detected VRAM RAM=2048M, BAR=256M > [ 9.125000] [drm] RAM width 128bits DDR > [ 9.125000] [drm] radeon: 2048M of VRAM memory ready > [ 9.125000] [drm] radeon: 2048M of GTT memory ready. > [ 9.125000] [drm] Loading oland Microcode > [ 9.128906] [drm] Internal thermal controller with fan control > [ 9.128906] Unable to handle kernel paging request at virtual address 000000000000003c > [ 9.128906] CPU 3 systemd-udevd(148): Oops 0 > [ 9.128906] pc = [] ra = [] ps = 0000 Not tainted > [ 9.128906] pc is at drm_pcie_get_speed_cap_mask+0x3c/0x12c > [ 9.128906] ra is at si_dpm_init+0x64/0x1398 [radeon] > [ 9.128906] v0 = ffffffffffffffea t0 = fffffc07fcc3a400 t1 = 0000000000001106 > [ 9.128906] t2 = 0000000000001166 t3 = 0000000000000000 t4 = fffffc018eafc000 > [ 9.128906] t5 = ffffffffffffff80 t6 = 000000000000003f t7 = fffffc07f6a90000 > [ 9.128906] s0 = fffffc07f6a9390c s1 = 0000000000000000 s2 = fffffc07f59119b0 > [ 9.128906] s3 = 0000000000000001 s4 = fffffffffffffff4 s5 = fffffc07f5910000 > [ 9.128906] s6 = 0000000000000000 > [ 9.128906] a0 = fffffc07f706c800 a1 = fffffc07f6a9390c a2 = fffffffffffffffc > [ 9.128906] a3 = ffffffff815fb510 a4 = ffffffff815fb4c8 a5 = 0000000000000000 > [ 9.128906] t8 = 000000000000007f t9 = ffffffff80d86c14 t10= 0000000000000001 > [ 9.128906] t11= 00000000000003c0 pv = ffffffff80e637e8 at = 0000000000000000 > [ 9.128906] gp = ffffffff815e9230 sp = fffffc07f6a93868 > [ 9.128906] Disabling lock debugging due to kernel taint > [ 9.128906] Trace: > [ 9.128906] [] drm_dev_register+0xb0/0x138 > [ 9.128906] [] drm_get_pci_dev+0x120/0x208 > [ 9.128906] [] local_pci_probe+0x38/0x8c > [ 9.128906] [] pci_device_probe+0x170/0x1d0 > [ 9.128906] [] driver_probe_device+0x168/0x2fc > [ 9.128906] [] __driver_attach+0x94/0xe8 > [ 9.128906] [] bus_for_each_dev+0x94/0xd4 > [ 9.128906] [] __driver_attach+0x0/0xe8 > [ 9.128906] [] driver_attach+0x2c/0x40 > [ 9.128906] [] bus_add_driver+0x140/0x2d4 > [ 9.128906] [] driver_register+0x100/0x180 > [ 9.128906] [] __pci_register_driver+0x48/0x5c > [ 9.128906] [] drm_pci_init+0x7c/0x168 > [ 9.128906] [] do_one_initcall+0x188/0x25c > [ 9.128906] [] do_init_module+0x8c/0x2c8 > [ 9.128906] [] kmem_cache_alloc+0x1f8/0x22c > [ 9.128906] [] do_init_module+0x40/0x2c8 > [ 9.128906] [] load_module+0x1ea8/0x263c > [ 9.128906] [] unknown_module_param_cb+0x0/0xc8 > [ 9.128906] [] SYSC_finit_module+0x94/0xb4 > [ 9.128906] [] module_notes_read+0x0/0x4c > [ 9.128906] [] entSys+0xa0/0xc0 Grepping on entSys the only mention is on alpha. Is dev->pdev->bus->parent NULL by any chance? > [ 9.128906] Code: 8c300188 c020003b 8c210010 f85f1106 f87f1166 8d410038 <842a003c> 40220502 > [ 9.128906] systemd-udevd[136]: worker [148] terminated by signal 11 (Segmentation fault) > > Signed-off-by: Caicai > --- > drivers/gpu/drm/drm_pci.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/drm_pci.c b/drivers/gpu/drm/drm_pci.c > index 4db9c515b74f..3d1cd760b79c 100644 > --- a/drivers/gpu/drm/drm_pci.c > +++ b/drivers/gpu/drm/drm_pci.c > @@ -332,10 +332,12 @@ int drm_pcie_get_speed_cap_mask(struct drm_device *dev, u32 *mask) > u32 lnkcap, lnkcap2; > > *mask = 0; > - if (!dev->pdev) > + if (!dev->pdev || !dev->pdev->bus) > return -EINVAL; I think we can assume our device is on a bus. > root = dev->pdev->bus->self; > + if (!root) > + return -EINVAL; I'm not a PCI expert, but seems like a bad design to say none of the speeds are supported just because we lack a bridge. btw, drm_pcie_get_max_link_width is similarly affected. ~Maarten