From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751173AbeCIKoj (ORCPT ); Fri, 9 Mar 2018 05:44:39 -0500 Received: from mga04.intel.com ([192.55.52.120]:65142 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751113AbeCIKoi (ORCPT ); Fri, 9 Mar 2018 05:44:38 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.47,445,1515484800"; d="scan'208";a="23282162" From: Mika Westerberg To: linux-kernel@vger.kernel.org Cc: Andreas Noever , Michael Jamet , Yehezkel Bernat , Jordan Glover , Kai-Heng Feng , Mika Westerberg Subject: [PATCH] thunderbolt: Prevent crash when ICM firmware is not running Date: Fri, 9 Mar 2018 13:44:34 +0300 Message-Id: <20180309104434.64412-1-mika.westerberg@linux.intel.com> X-Mailer: git-send-email 2.16.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Lenovo ThinkPad Yoga 370 (and possibly some other Lenovo models as well) the Thunderbolt host controller sometimes comes up in such way that the ICM firmware is not running properly. This is most likely an issue in BIOS/firmware but as side-effect driver crashes the kernel due to NULL pointer dereference: BUG: unable to handle kernel NULL pointer dereference at 0000000000000980 IP: pci_write_config_dword+0x5/0x20 Call Trace: pcie2cio_write+0x3b/0x70 [thunderbolt] icm_driver_ready+0x168/0x260 [thunderbolt] ? tb_ctl_start+0x50/0x70 [thunderbolt] tb_domain_add+0x73/0xf0 [thunderbolt] nhi_probe+0x182/0x300 [thunderbolt] local_pci_probe+0x42/0xa0 ? pci_match_device+0xd9/0x100 pci_device_probe+0x146/0x1b0 driver_probe_device+0x315/0x480 ... Instead of crashing update the driver to bail out gracefully if we encounter such situation. Fixes: f67cf491175a ("thunderbolt: Add support for Internal Connection Manager (ICM)") Reported-by: Jordan Glover Signed-off-by: Mika Westerberg Cc: stable@vger.kernel.org --- drivers/thunderbolt/icm.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/thunderbolt/icm.c b/drivers/thunderbolt/icm.c index 6b1041677604..2d2ceda9aa26 100644 --- a/drivers/thunderbolt/icm.c +++ b/drivers/thunderbolt/icm.c @@ -1452,6 +1452,9 @@ static int icm_firmware_reset(struct tb *tb, struct tb_nhi *nhi) struct icm *icm = tb_priv(tb); u32 val; + if (!icm->upstream_port) + return -ENODEV; + /* Put ARC to wait for CIO reset event to happen */ val = ioread32(nhi->iobase + REG_FW_STS); val |= REG_FW_STS_CIO_RESET_REQ; -- 2.16.1