From patchwork Fri May 11 17:57:24 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joseph Salisbury X-Patchwork-Id: 912098 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=lists.ubuntu.com (client-ip=91.189.94.19; helo=huckleberry.canonical.com; envelope-from=kernel-team-bounces@lists.ubuntu.com; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=canonical.com Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 40jHqk0sxjz9s1p; Sat, 12 May 2018 03:57:38 +1000 (AEST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.86_2) (envelope-from ) id 1fHCIL-0001nb-Bo; Fri, 11 May 2018 17:57:29 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtps (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:128) (Exim 4.86_2) (envelope-from ) id 1fHCIH-0001lX-Mj for kernel-team@lists.ubuntu.com; Fri, 11 May 2018 17:57:25 +0000 Received: from 1.general.jsalisbury.us.vpn ([10.172.67.212] helo=salisbury) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1fHCIH-0003QU-8O for kernel-team@lists.ubuntu.com; Fri, 11 May 2018 17:57:25 +0000 Received: by salisbury (Postfix, from userid 1000) id 137F47E0495; Fri, 11 May 2018 13:57:24 -0400 (EDT) From: Joseph Salisbury To: kernel-team@lists.ubuntu.com Subject: [SRU][Artful][v2][PATCH 1/1] drm/i915/bios: filter out invalid DDC pins from VBT child devices Date: Fri, 11 May 2018 13:57:24 -0400 Message-Id: X-Mailer: git-send-email 2.17.0 In-Reply-To: References: In-Reply-To: References: X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.20 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: "kernel-team" From: Jani Nikula BugLink: http://bugs.launchpad.net/bugs/1764194 The VBT contains the DDC pin to use for specific ports. Alas, sometimes the field appears to contain bogus data, and while we check for it later on in intel_gmbus_get_adapter() we fail to check the returned NULL on errors. Oops results. The simplest approach seems to be to catch and ignore the bogus DDC pins already at the VBT parsing phase, reverting to fixed per port default pins. This doesn't guarantee display working, but at least it prevents the oops. And we continue to be fuzzed by VBT. One affected machine is Dell Latitude 5590 where a BIOS upgrade added invalid DDC pins. Typical backtrace: [ 35.461411] WARN_ON(!intel_gmbus_is_valid_pin(dev_priv, pin)) [ 35.461432] WARNING: CPU: 6 PID: 411 at drivers/gpu/drm/i915/intel_i2c.c:844 intel_gmbus_get_adapter+0x32/0x37 [i915] [ 35.461437] Modules linked in: i915 ahci libahci dm_snapshot dm_bufio dm_raid raid456 async_raid6_recov async_pq raid6_pq async_xor xor async_memcpy async_tx [ 35.461445] CPU: 6 PID: 411 Comm: kworker/u16:2 Not tainted 4.16.0-rc7.x64-g1cda370ffded #1 [ 35.461447] Hardware name: Dell Inc. Latitude 5590/0MM81M, BIOS 1.1.9 03/13/2018 [ 35.461450] Workqueue: events_unbound async_run_entry_fn [ 35.461465] RIP: 0010:intel_gmbus_get_adapter+0x32/0x37 [i915] [ 35.461467] RSP: 0018:ffff9b4e43d47c40 EFLAGS: 00010286 [ 35.461469] RAX: 0000000000000000 RBX: ffff98f90639f800 RCX: ffffffffae051960 [ 35.461471] RDX: 0000000000000001 RSI: 0000000000000092 RDI: 0000000000000246 [ 35.461472] RBP: ffff98f905410000 R08: 0000004d062a83f6 R09: 00000000000003bd [ 35.461474] R10: 0000000000000031 R11: ffffffffad4eda58 R12: ffff98f905410000 [ 35.461475] R13: ffff98f9064c1000 R14: ffff9b4e43d47cf0 R15: ffff98f905410000 [ 35.461477] FS: 0000000000000000(0000) GS:ffff98f92e580000(0000) knlGS:0000000000000000 [ 35.461479] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 35.461481] CR2: 00007f5682359008 CR3: 00000001b700c005 CR4: 00000000003606e0 [ 35.461483] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 35.461484] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 35.461486] Call Trace: [ 35.461501] intel_hdmi_set_edid+0x37/0x27f [i915] [ 35.461515] intel_hdmi_detect+0x7c/0x97 [i915] [ 35.461518] drm_helper_probe_single_connector_modes+0xe1/0x6c0 [ 35.461521] drm_setup_crtcs+0x129/0xa6a [ 35.461523] ? __switch_to_asm+0x34/0x70 [ 35.461527] ? __switch_to_asm+0x40/0x70 [ 35.461528] ? __switch_to_asm+0x34/0x70 [ 35.461529] ? __switch_to_asm+0x40/0x70 [ 35.461531] ? __switch_to_asm+0x34/0x70 [ 35.461532] ? __switch_to_asm+0x40/0x70 [ 35.461534] ? __switch_to_asm+0x34/0x70 [ 35.461536] __drm_fb_helper_initial_config_and_unlock+0x34/0x46f [ 35.461538] ? __switch_to_asm+0x40/0x70 [ 35.461541] ? _cond_resched+0x10/0x33 [ 35.461557] intel_fbdev_initial_config+0xf/0x1c [i915] [ 35.461560] async_run_entry_fn+0x2e/0xf5 [ 35.461563] process_one_work+0x15b/0x364 [ 35.461565] worker_thread+0x2c/0x3a0 [ 35.461567] ? process_one_work+0x364/0x364 [ 35.461568] kthread+0x10c/0x122 [ 35.461570] ? _kthread_create_on_node+0x5d/0x5d [ 35.461572] ret_from_fork+0x35/0x40 [ 35.461574] Code: 74 16 89 f6 48 8d 04 b6 48 c1 e0 05 48 29 f0 48 8d 84 c7 e8 11 00 00 c3 48 c7 c6 b0 19 1e c0 48 c7 c7 64 8a 1c c0 e8 47 88 ed ec <0f> 0b 31 c0 c3 8b 87 a4 04 00 00 80 e4 fc 09 c6 89 b7 a4 04 00 [ 35.461604] WARNING: CPU: 6 PID: 411 at drivers/gpu/drm/i915/intel_i2c.c:844 intel_gmbus_get_adapter+0x32/0x37 [i915] [ 35.461606] ---[ end trace 4fe1e63e2dd93373 ]--- [ 35.461609] BUG: unable to handle kernel NULL pointer dereference at 0000000000000010 [ 35.461613] IP: i2c_transfer+0x4/0x86 [ 35.461614] PGD 0 P4D 0 [ 35.461616] Oops: 0000 [#1] SMP PTI [ 35.461618] Modules linked in: i915 ahci libahci dm_snapshot dm_bufio dm_raid raid456 async_raid6_recov async_pq raid6_pq async_xor xor async_memcpy async_tx [ 35.461624] CPU: 6 PID: 411 Comm: kworker/u16:2 Tainted: G W 4.16.0-rc7.x64-g1cda370ffded #1 [ 35.461625] Hardware name: Dell Inc. Latitude 5590/0MM81M, BIOS 1.1.9 03/13/2018 [ 35.461628] Workqueue: events_unbound async_run_entry_fn [ 35.461630] RIP: 0010:i2c_transfer+0x4/0x86 [ 35.461631] RSP: 0018:ffff9b4e43d47b30 EFLAGS: 00010246 [ 35.461633] RAX: ffff9b4e43d47b6e RBX: 0000000000000005 RCX: 0000000000000001 [ 35.461635] RDX: 0000000000000002 RSI: ffff9b4e43d47b80 RDI: 0000000000000000 [ 35.461636] RBP: ffff9b4e43d47bd8 R08: 0000004d062a83f6 R09: 00000000000003bd [ 35.461638] R10: 0000000000000031 R11: ffffffffad4eda58 R12: 0000000000000002 [ 35.461639] R13: 0000000000000001 R14: ffff9b4e43d47b6f R15: ffff9b4e43d47c07 [ 35.461641] FS: 0000000000000000(0000) GS:ffff98f92e580000(0000) knlGS:0000000000000000 [ 35.461643] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 35.461645] CR2: 0000000000000010 CR3: 00000001b700c005 CR4: 00000000003606e0 [ 35.461646] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 35.461647] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 35.461649] Call Trace: [ 35.461652] drm_do_probe_ddc_edid+0xb3/0x128 [ 35.461654] drm_get_edid+0xe5/0x38d [ 35.461669] intel_hdmi_set_edid+0x45/0x27f [i915] [ 35.461684] intel_hdmi_detect+0x7c/0x97 [i915] [ 35.461687] drm_helper_probe_single_connector_modes+0xe1/0x6c0 [ 35.461689] drm_setup_crtcs+0x129/0xa6a [ 35.461691] ? __switch_to_asm+0x34/0x70 [ 35.461693] ? __switch_to_asm+0x34/0x70 [ 35.461694] ? __switch_to_asm+0x40/0x70 [ 35.461696] ? __switch_to_asm+0x34/0x70 [ 35.461697] ? __switch_to_asm+0x40/0x70 [ 35.461698] ? __switch_to_asm+0x34/0x70 [ 35.461700] ? __switch_to_asm+0x40/0x70 [ 35.461701] ? __switch_to_asm+0x34/0x70 [ 35.461703] __drm_fb_helper_initial_config_and_unlock+0x34/0x46f [ 35.461705] ? __switch_to_asm+0x40/0x70 [ 35.461707] ? _cond_resched+0x10/0x33 [ 35.461724] intel_fbdev_initial_config+0xf/0x1c [i915] [ 35.461727] async_run_entry_fn+0x2e/0xf5 [ 35.461729] process_one_work+0x15b/0x364 [ 35.461731] worker_thread+0x2c/0x3a0 [ 35.461733] ? process_one_work+0x364/0x364 [ 35.461734] kthread+0x10c/0x122 [ 35.461736] ? _kthread_create_on_node+0x5d/0x5d [ 35.461738] ret_from_fork+0x35/0x40 [ 35.461739] Code: 5c fa e1 ad 48 89 df e8 ea fb ff ff e9 2a ff ff ff 0f 1f 44 00 00 31 c0 e9 43 fd ff ff 31 c0 45 31 e4 e9 c5 fd ff ff 41 54 55 53 <48> 8b 47 10 48 83 78 10 00 74 70 41 89 d4 48 89 f5 48 89 fb 65 [ 35.461756] RIP: i2c_transfer+0x4/0x86 RSP: ffff9b4e43d47b30 [ 35.461757] CR2: 0000000000000010 [ 35.461759] ---[ end trace 4fe1e63e2dd93374 ]--- Based on a patch by Fei Li. v2: s/reverting/sticking/ (Chris) Cc: stable@vger.kernel.org Cc: Fei Li Co-developed-by: Fei Li Reported-by: Pavel Nakonechnyi Reported-and-tested-by: Seweryn Kokot Reported-and-tested-by: Laszlo Valko Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=105549 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=105961 Reviewed-by: Chris Wilson Signed-off-by: Jani Nikula Link: https://patchwork.freedesktop.org/patch/msgid/20180411131519.9091-1-jani.nikula@intel.com (cherry picked from commit f212bf9abe5de9f938fecea7df07046e74052dde) Signed-off-by: Joonas Lahtinen (back ported from commit a3520b8992e57bc94ab6ec9f95f09c6c932555fd) Signed-off-by: Joseph Salisbury Acked-by: Kleber Sacilotto de Souza --- drivers/gpu/drm/i915/intel_bios.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c index 0be1d38..3250acb 100644 --- a/drivers/gpu/drm/i915/intel_bios.c +++ b/drivers/gpu/drm/i915/intel_bios.c @@ -1156,7 +1156,6 @@ static void parse_ddi_port(struct drm_i915_private *dev_priv, enum port port, return; aux_channel = child->common.aux_channel; - ddc_pin = child->common.ddc_pin; is_dvi = child->common.device_type & DEVICE_TYPE_TMDS_DVI_SIGNALING; is_dp = child->common.device_type & DEVICE_TYPE_DISPLAYPORT_OUTPUT; @@ -1196,9 +1195,15 @@ static void parse_ddi_port(struct drm_i915_private *dev_priv, enum port port, DRM_DEBUG_KMS("Port %c is internal DP\n", port_name(port)); if (is_dvi) { - info->alternate_ddc_pin = ddc_pin; - - sanitize_ddc_pin(dev_priv, port); + ddc_pin = child->common.ddc_pin; + if (intel_gmbus_is_valid_pin(dev_priv, ddc_pin)) { + info->alternate_ddc_pin = ddc_pin; + sanitize_ddc_pin(dev_priv, port); + } else { + DRM_DEBUG_KMS("Port %c has invalid DDC pin %d, " + "sticking to defaults\n", + port_name(port), ddc_pin); + } } if (is_dp) {