From patchwork Fri Mar 5 12:38:56 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Assmann X-Patchwork-Id: 394163 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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS 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 74C74C4332D for ; Fri, 5 Mar 2021 12:40:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4A99C64EE8 for ; Fri, 5 Mar 2021 12:40:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233069AbhCEMju convert rfc822-to-8bit (ORCPT ); Fri, 5 Mar 2021 07:39:50 -0500 Received: from us-smtp-delivery-44.mimecast.com ([207.211.30.44]:42508 "EHLO us-smtp-delivery-44.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232983AbhCEMj1 (ORCPT ); Fri, 5 Mar 2021 07:39:27 -0500 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-185-3gWCCtCyN3CXF2ZOze5HQg-1; Fri, 05 Mar 2021 07:39:10 -0500 X-MC-Unique: 3gWCCtCyN3CXF2ZOze5HQg-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 75ED7814339; Fri, 5 Mar 2021 12:39:09 +0000 (UTC) Received: from p50.redhat.com (unknown [10.40.194.61]) by smtp.corp.redhat.com (Postfix) with ESMTP id DCC175D6B1; Fri, 5 Mar 2021 12:39:07 +0000 (UTC) From: Stefan Assmann To: intel-wired-lan@lists.osuosl.org Cc: netdev@vger.kernel.org, anthony.l.nguyen@intel.com, lihong.yang@intel.com, sassmann@kpanic.de Subject: [PATCH] iavf: do not override the adapter state in the watchdog task Date: Fri, 5 Mar 2021 13:38:56 +0100 Message-Id: <20210305123856.14302-1-sassmann@kpanic.de> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: kpanic.de Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The iavf watchdog task overrides adapter->state to __IAVF_RESETTING when it detects a pending reset. Then schedules iavf_reset_task() which takes care of the reset. The reset task is capable of handling the reset without changing adapter->state. In fact we lose the state information when the watchdog task prematurely changes the adapter state. This may lead to a crash if instead of the reset task the iavf_remove() function gets called before the reset task. In that case (if we were in state __IAVF_RUNNING previously) the iavf_remove() function triggers iavf_close() which fails to close the device because of the incorrect state information. This may result in a crash due to pending interrupts. kernel BUG at drivers/pci/msi.c:357! [...] Call Trace: [] pci_disable_msix+0x3d/0x50 [] iavf_reset_interrupt_capability+0x23/0x40 [iavf] [] iavf_remove+0x10a/0x350 [iavf] [] pci_device_remove+0x39/0xc0 [] __device_release_driver+0x7f/0xf0 [] device_release_driver+0x23/0x30 [] pci_stop_bus_device+0x84/0xa0 [] pci_stop_and_remove_bus_device+0x12/0x20 [] pci_iov_remove_virtfn+0xaf/0x160 [] sriov_disable+0x3c/0xf0 [] pci_disable_sriov+0x23/0x30 [] i40e_free_vfs+0x265/0x2d0 [i40e] [] i40e_pci_sriov_configure+0x144/0x1f0 [i40e] [] sriov_numvfs_store+0x177/0x1d0 Code: 00 00 e8 3c 25 e3 ff 49 c7 86 88 08 00 00 00 00 00 00 5b 41 5c 41 5d 41 5e 41 5f 5d c3 48 8b 7b 28 e8 0d 44 RIP [] free_msi_irqs+0x188/0x190 The solution is to not touch the adapter->state in iavf_watchdog_task() and let the reset task handle the state transition. Signed-off-by: Stefan Assmann Tested-by: Konrad Jankowski --- drivers/net/ethernet/intel/iavf/iavf_main.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c index 0a867d64d467..d9e3a70abb47 100644 --- a/drivers/net/ethernet/intel/iavf/iavf_main.c +++ b/drivers/net/ethernet/intel/iavf/iavf_main.c @@ -1954,7 +1954,6 @@ static void iavf_watchdog_task(struct work_struct *work) /* check for hw reset */ reg_val = rd32(hw, IAVF_VF_ARQLEN1) & IAVF_VF_ARQLEN1_ARQENABLE_MASK; if (!reg_val) { - adapter->state = __IAVF_RESETTING; adapter->flags |= IAVF_FLAG_RESET_PENDING; adapter->aq_required = 0; adapter->current_op = VIRTCHNL_OP_UNKNOWN;