From patchwork Thu Feb 11 15:02:47 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 381746 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=-19.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 25370C433E0 for ; Thu, 11 Feb 2021 15:25:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DD10F64E8B for ; Thu, 11 Feb 2021 15:25:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231166AbhBKPYz (ORCPT ); Thu, 11 Feb 2021 10:24:55 -0500 Received: from mail.kernel.org ([198.145.29.99]:52626 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229700AbhBKPUg (ORCPT ); Thu, 11 Feb 2021 10:20:36 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 6230964F26; Thu, 11 Feb 2021 15:06:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1613056004; bh=a7cpqNj4McTknLDLJ6IE1wMgM7KtFiLedfkTpgs8aEU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gVHdzKiD7k/z2zenx5H6f9IV8e+1SGfHCZArt/o7vibnJmIbSDq3ZOQi2oS3Sbnf1 0N5lT7Zr7zcZy0T+EoNs//sGY+yNv2KFdoqn6OTImINKZAo9xenqub6p3aG4GS3LP5 JQC+ke60evDiDJGRosjRPdX9iEv6kFfZzGwk6RZc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Johannes Berg , Luca Coelho , Kalle Valo , Sasha Levin Subject: [PATCH 4.19 13/24] iwlwifi: mvm: guard against device removal in reprobe Date: Thu, 11 Feb 2021 16:02:47 +0100 Message-Id: <20210211150148.335575799@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210211150147.743660073@linuxfoundation.org> References: <20210211150147.743660073@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Johannes Berg [ Upstream commit 7a21b1d4a728a483f07c638ccd8610d4b4f12684 ] If we get into a problem severe enough to attempt a reprobe, we schedule a worker to do that. However, if the problem gets more severe and the device is actually destroyed before this worker has a chance to run, we use a free device. Bump up the reference count of the device until the worker runs to avoid this situation. Signed-off-by: Johannes Berg Signed-off-by: Luca Coelho Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/iwlwifi.20210122144849.871f0892e4b2.I94819e11afd68d875f3e242b98bef724b8236f1e@changeid Signed-off-by: Sasha Levin --- drivers/net/wireless/intel/iwlwifi/mvm/ops.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/ops.c b/drivers/net/wireless/intel/iwlwifi/mvm/ops.c index 0e26619fb330b..d932171617e6a 100644 --- a/drivers/net/wireless/intel/iwlwifi/mvm/ops.c +++ b/drivers/net/wireless/intel/iwlwifi/mvm/ops.c @@ -1192,6 +1192,7 @@ static void iwl_mvm_reprobe_wk(struct work_struct *wk) reprobe = container_of(wk, struct iwl_mvm_reprobe, work); if (device_reprobe(reprobe->dev)) dev_err(reprobe->dev, "reprobe failed!\n"); + put_device(reprobe->dev); kfree(reprobe); module_put(THIS_MODULE); } @@ -1242,7 +1243,7 @@ void iwl_mvm_nic_restart(struct iwl_mvm *mvm, bool fw_error) module_put(THIS_MODULE); return; } - reprobe->dev = mvm->trans->dev; + reprobe->dev = get_device(mvm->trans->dev); INIT_WORK(&reprobe->work, iwl_mvm_reprobe_wk); schedule_work(&reprobe->work); } else if (mvm->fwrt.cur_fw_img == IWL_UCODE_REGULAR &&